Negative Scan Research Articles

Abstract 15218: Hereditary Transthyretin Cardiac Amyloidosis in a Patient at High Risk for Plasma Cell Dyscrasias: A Complex Diagnostic Work-Up

Background: Cardiac amyloidosis (CA) is most commonly caused by the infiltration of misfolded amyloid transthyretin (ATTR) or light chain (AL) molecules in the myocardium. The workup for CA requires serum assessment to exclude the rapidly progressive AL subtype before imaging to assess the more common and indolent ATTR form. The diagnostic algorithm has the potential to become complex as in this case about a woman with Sjogren’s syndrome which predisposes to plasma cell dyscrasias. Case: A 68-year-old female with congenital long QT syndrome requiring implantable cardioverter-defibrillator (ICD), bilateral carpal tunnel, and recent diagnosis of Sjogren’s syndrome was found to have new systolic heart failure during workup for interstitial lung disease. Labs revealed pancytopenia, abnormal kappa/lambda ratio (2.25), and polyclonal gammopathy on immunofixation. Echocardiogram showed moderately reduced systolic function with an ejection fraction of 35-40% and moderate concentric left ventricular hypertrophy. Decision-making: Cardiology obtained cardiac magnetic resonance imaging (CMR) that returned indeterminate due to ICD artifact. Hematology performed a bone marrow biopsy that was negative for plasma cell dyscrasia, though stained positive for amyloid on congo red with mass spectrometry revealing the valine 142 isoleucine (Val142Ile) amino acid substitution consistent with hereditary ATTR-CA. To definitively assess for endomyocardial ATTR involvement the patient was sent for cardiac scintigraphy using 99mTc-labeled pyrophosphate which returned negative with a cardiac to contralateral lung uptake ratio of 1.001 and visual grade of 0. With suspicion still high, an endomyocardial biopsy was pursued and stained positive for congo red with mass spectrometry confirming hereditary Val142Ile ATTR-CA, allowing for tafamidis initiation. Conclusion: We present a complex diagnostic case of ATTR amyloid in a patient who is at high risk for plasma cell dyscrasias with an abnormal kappa/lambda ratio, non-diagnostic CMR, and negative nuclear scan. Despite significant advances in imaging techniques allowing for less invasive diagnostics, this case highlights the role of endomyocardial biopsy in complicated cases.

Abstract 14073: Hypercalcemia Induced Reversible LBBB

Background: Parathyroid hormone (PTH) and calcitriol are the two hormones responsible for calcium and phosphate homeostasis. PTH exerts its effect on the renal tubular calcium reabsorption and bone resorption. PTH secretion is modulated by calcium acting on the sensitive calcium-sensing receptor on the parathyroid cells. Primary hyperparathyroidism has been linked to hypertension and valvular calcification. Structural changes are also seen including elevated left ventricular mass, diastolic dysfunction and myocardial calcification. Case presentation: A 61-year old female with hyperlipidemia and osteoporosis presented with polyarticular joint pain and diffuse myalgia noted to have elevated PTH of 90 pg/ml and elevated Ca of 10.1 mg/dl. Her calcium levels has ranged from 10.1 to 11.2 mg/dl and her PTH ranged from 90 to 113 pg/ml. She had a negative sestamibi scan, and thyroid ultrasound showed fusiform lesion measuring 0.82 x 0.36 in the right posterior neck suspicious for a parathyroid adenoma with the plan made for resection. The diagnosis at this time was primary hyperparathyroidism induced hypercalcemia. She developed exertional dizziness and was found to have a new LBBB and reduced ejection fraction of 40-45% with a small fixed defect in the septal area which was attributed to the LBBB. She was initiated on metoprolol succinate 25 mg, irbesartan 75 mg, atorvastatin 40 mg and aspirin 81 mg because of the reduced systolic function. SPECT was negative for ischemia with a fixed decreased uptake of the septum. She underwent right lower parathyroid excision on 11/2021 with normalization of calcium to 9.4 mg/dl and PTH to 9 pg/ml with resolution of the LBBB and systolic function in 2/2021 improving to 48%. Discussion: Calcium plays a key role in cardiac excitation, depolarization, repolarization, and also coupling of these signals to mechanical contraction via calcium induced calcium release and myofibril cross linking. In this case, calcium was only mildly elevated to cause a partial conduction defect. Literature is lacking on whether there is a threshold level for calcium that predisposes to varying degrees of conduction disease. This case also highlights the temporal nature of symptom resolution following parathyroid surgery with resolution of the LBBB.

PSOR7 Presentation Time: 12:00 PM: Toxicity and Efficacity of Whole Gland Salvage HDR Brachytherapy After Primary Radiation for Prostate Cancer

<h3>Purpose</h3> Androgen Deprivation Therapy (ADT) is the most common treatment for relapsing prostate cancer after primary radiation therapy. However, an effective local treatment could be used to obtain local control of the disease while limiting the systemic side effects of ADT. We designed a single institution prospective pilot study to assess the efficacy and safety of whole gland prostate HDR brachytherapy. <h3>Materials and Methods</h3> Fifty (50) patients with local relapse after primary radiation therapy were included in this study. A biopsy-proven local relapse, a negative bone scan, and a negative CT scan of the abdomen and pelvis were mandatory. A dose of 32Gy in 4 fractions was delivered to the whole prostate by HDR brachytherapy using CT-based treatment planning. The use of ADT was allowed if deemed clinically indicated by the treating physician. The primary objective was to evaluate early and late gastrointestinal (GI) and genitourinary (GU) toxicities, assessed with CTCAE v5 scale and IPS score. Biochemical disease-free survival (bDFS) was evaluated as a secondary outcome. <h3>Results</h3> Median follow-up was 61,1 months (0.8-106.8 months). Sixteen (16) patients received short-course ADT prior to brachytherapy. GI toxicities were low, with no grade 3 toxicities reported. 4.1% and 14,6% of patients had early and late grade 2 toxicities. Only one patient had a grade 3 GU early toxicity. However, 16,7% of patients experienced late grade 3 toxicities (12.0% at the last follow-up). Interestingly, none of the patient using neoadjuvant ADT developed late grade 3 toxicities although this association was not statistically significant (Chi-Square p-value 0.171). Mean IPSS value presented a predictable rise to 15.9 at 1 month follow-up. A subsequent decline was observed to mean IPSS under 10 after 24 months. A bDFS of 73,5% was observed after 48 months. <h3>Conclusion</h3> Whole gland salvage HDR brachytherapy is an effective treatment with an excellent biochemical disease-free survival. However, it is associated with a significant risk of late GU toxicities. In this perspective, our treatment protocol has been modified to allow for focal therapy using MR guidance. That will allow us to evaluate if a similar local control can be maintained while reducing the incidence of severe toxicities.

PO50 Presentation Time: 10:00 AM: Long-Term Results of Salvage High Dose-Rate Brachytherapy with or without Pelvic External Beam Radiotherapy in Patients with Palpable Local Recurrence of Prostate Cancer After Radical Prostatectomy

<h3>Purpose</h3> This study aims to evaluate the long term outcomes and toxicities in patients with clinically apparent, gross local recurrence of prostate cancer after radical prostatectomy, treated with salvage high dose-rate brachytherapy (HDR-BT) with or without pelvic external beam radiotherapy (EBRT). <h3>Materials and Methods</h3> Retrospective chart review was performed to identify patients with clinically apparent, gross local recurrence of prostate cancer after radical prostatectomy who underwent salvage HDR-BT at a single institution between 2002 and 2020. HDR-BT regimens included 950 cGy x 2 (N=4), 1500 cGy x 1 (N=2), 950 cGy x 4 (N=1), and 800 cGy x 2 (N=1). Pelvic EBRT was allowed at the discretion of the treating physician. Treatment and clinical characteristics were obtained for each patient, and outcome and toxicity data were collected. Toxicity was graded according to Common Toxicity criteria for Adverse Events Version 5.0. Descriptive analysis was performed. <h3>Results</h3> A total of 8 patients were included in analysis with a median follow-up of 49 months (range: 9 to 223 months). Five (63%) patients presented with a biochemical recurrence, and 3 patients (38%) presented with symptoms including hematuria and urinary obstruction. Seven patients underwent TRUS-guided biopsy which confirmed recurrent adenocarcinoma. The remaining patient underwent a PSMA PET/CT scan revealing a PET-avid soft tissue lesion in the prostate bed, but declined biopsy and proceeded with treatment without pathologic confirmation. Median age at time of salvage brachytherapy was 68 years (range: 59 to 85 years). Median time from prostatectomy to salvage HDR-BT was 95 months (range: 19 to 207 months). Median PSA at time of HDR brachytherapy was 2.32 ng/ml (range: undetectable on ADT to 13 ng/ml). Median lesion size was 2.5 cm (range: 1 to 3.6 cm). Six patients (75%) received adjuvant pelvic EBRT, 45-50 Gy in 25 fractions. Seven out of 8 patients received ADT after salvage brachytherapy for a median duration of 12 months (range: 8 to 24 months). The remaining patient did not receive ADT due to cardiac comorbidities. Seven out of 8 patients were alive at last follow-up. There have been no locoregional recurrences. Three patients developed distant metastatic disease. One patient, who had negative conventional staging scans 3 months prior to brachytherapy, was found to have distant metastatic disease only 2 months after salvage brachytherapy and died due to metastatic prostate cancer 9 months after HDR-BT. The other 2 patients developed distant metastases at 14 and 27 months after brachytherapy. One patient developed late grade 3 urinary incontinence requiring artificial urinary sphincter (AUS) placement 18 months after brachytherapy. This patient had the largest tumor size, 3.6 cm in longest dimension, and received pelvic EBRT in addition to HDR-BT. He is now more than 10 years out from HDR-BT with undetectable PSA and doing well with his AUS. There were no other grade 2 or higher genitourinary or gastrointestinal toxicities. <h3>Conclusions</h3> This study demonstrates the long-term safety and efficacy of salvage HDR brachytherapy in the setting of clinically apparent local recurrence of prostate cancer after radical prostatectomy, with durable locoregional control and acceptable rates of toxicity. HDR-BT should be further explored as an option for dose-escalated salvage radiotherapy in patients with gross local recurrences after radical prostatectomy.

ODP499 Myxedema Coma: A Challenging Presentation of an Uncommon Disease

Abstract Myxedema coma is a rare diagnosis but if not early recognized, this medical emergency possesses a high mortality rate. Over the years, it has been described predominantly in elderly women with history of hypothyroidism and as a precipitant factor that converges to evolve in a full presentation. We report a case of myxedema coma in a young male without risks for this disease. A 38 y/o Latin-American male with medical history ofhepatitis C virus and intravenous drug abuser that was brought to the emergency department after being found in the streets. The patient was agitated, oriented only to person, had slurred speech and reports last dose of heroin was two days ago. Denied other condition or medications. Vital signs BP 103/90mmHg, pulse: 41 bpm, T: 35.8°C RR: 19 rpm, SPO2: 99% at room air and BMI: 23.9. kg/m 2 . Physical examination pertinent for a disheveled male with anasarca, diffused dry skin with piloerection without surgery scars, non-palpable nor tender thyroid gland, bilateral exophthalmos, decreased bowel sound, positive fluid wave and abdomen diffusely tender to palpation with bilateral lower extremities infected ulcers. Blood workup showed impaired renal function, severe azotemia, hyponatremia, hypoglycemia and normocytic anemia. TSH 147uIU/mL. Imaging studies remarkable for bilateral pleural effusions, intestinal ileus, and negative brain CT scan. Patient was admitted with diagnosis of uremic encephalopathy, drug withdrawal and soft skin tissue infection. Patient was treated with emergent hemodialysis, drug withdrawal measures and IV antibiotics. Despite treatment, patient's clinical condition began to decline. He was found obtunded requiring endotracheal intubation. TSH was persistently elevated in 55.7uIU/mL with suppressed free T4 &amp;lt;0.42ng/dL. Patient noted with persistent sinus bradycardia, hypothermia, ileus, ascites, bilateral pleural effusions, and hypotension. Patient was consulted to endocrinology department who evaluated the overall clinical presentation and myxedema coma was diagnosed. He was treated with levothyroxine 100mg IV for two days, but eventually developed multiorgan failure and unfortunately died. Myxedema coma is a complication of severe hypothyroidism that slows down the functions of multiple organs and directly affects their function. It is an endocrinologic emergency that leads to decline of the clinical presentation of patients. The epidemiology favors this presentation in patients with history of hypothyroidism, more specifically elderly women. Multiple conditions may present with similar signs and symptoms. Physicians must be aware that myxedema coma must be suspected in a patient with altered mental status, hypothermia, hypoglycemia, hypotension, anasarca among others even in the presence of more common conditions and in rare populations like our patient. Opioid Induced Endocrinopathies still remain a complication that is underdiagnosed. The aim of this case is to createmedical awareness on the importanceto consider myxedema coma in patients with Opioid abuse and withdrawal. Presentation: No date and time listed

ODP648 MEN1 vs MEN4: when we cannot find a mutation

Abstract MEN1 is an autosomal dominant syndrome characterized by involvement of several endocrine and non-endocrine organs. The most common endocrine organs that are affected include pituitary, parathyroid, and/or pancreas. In 10-30% of patients, no germline mutations in the menin gene are identified, presenting a diagnostic challenge. This case raises the question of possible MEN4 syndrome, which shares a similar phenotype to MEN 1 with germline mutation in CDKN1B. Clinical case 59 y/o female with PMH HTN, obesity, hypothyroidism initially presented to our clinic in 2018 for evaluation of hypercalcemia. She prior was seen in 2005 for evaluation of prolactinoma by outside endocrinologist but was lost to follow up. Per history, she had a pituitary MRI in 1991 for work up of amenorrhea and found to have prolactinoma. She was placed on bromocriptine at that time; after repeat pituitary MRI and prolactin levels were found to be normal, bromocriptine was discontinued in 2019 but then restarted a few months later due to uptrending prolactin level. During the visit with us, work up for her hypercalcemia included calcium of 11. 0 mg/dL and PTH level of 93 pg/mL with normal albumin, vitamin D, and renal function. Patient had a negative sestamibi scan but was found to have a 10 mm×5 mm×12 mm enhancing nodule along the left thyroid gland and along left lateral margin of esophagus, suggesting parathyroid adenoma. She subsequently underwent successful left inferior parathyroidectomy in July 2019 with normalization of calcium and PTH levels. No other parathyroid was found to be enlarged. Given her pituitary and parathyroid adenoma, she was sent for genetic testing; she was evaluated for 7 gene variants and all were found negative including MEN1, CDKN1B, GNA11, AP2S1, CASR, CDC73, and RET. Of note, she has no family history of MEN1 or any endocrine tumors. However, further testing was still performed to evaluate for a pancreatic neuroendocrine tumor including CT abdomen, gastrin, C peptide, chromogranin-A, glucagon, VIP, and 5-HIAA. Her initial testing came back normal including normal CT abdomen in 2020. However, her most recently lab results in 2021 revealed an elevated gastrin level of 124 pg/mL and uptrending chromogranin A of 262 ng/mL (&amp;lt;=93), the diagnosis of gastrinoma was confirmed and PPIs were started. Discussion This case highlights the importance of continued surveillance in patients with multiple endocrine organ involvement or neoplasia despite negative genetic testing; it also supports the likelihood of unidentified mutations given the improbable chance this patient has 3 independent endocrine tumors. Possibilities including missed germline mutations on testing or phenocopies. This patient likely has an upstream mutation that was not identified and could represent either MEN1 vs MEN4 Presentation: No date and time listed

COVID-19 and Other Pneumonia Diagnosis Using CNN

Abstract: In the present scenario, a novel virus called COVID-19 is one of the substantial snags to the humans in this contemporary era. The present pace at which the virus is spreading has led to a significant spike in death rates across the globe, including in all countries and towns. In order to treat the ailment, one must therefore come up with a quick and accurate diagnosis. Deep learning has made a significant contribution to medical research, opening up new paths and opportunities for disease diagnosis methods. To counteract the COVID-19 outbreak, here we create a classifier distinguishing between positive and negative COVID scans. This study suggests a technique that utilizes chest X-ray images to first classify a patient into one of the bacterial or viral classifications, then further subclassifies them into one of the COVID-19 classes (Positive-1 &amp; Negative-0).

Diagnostic efficacy of positron emission computerized tomography scans in suspicious laryngeal findings postorgan preservation treatment.

Larynx preservation protocols (LPP) for glottic primary squamous cell carcinoma has gained popularity worldwide. Direct laryngoscopy (DL) with biopsy is mandated when recurrence is suspected. The efficacy of 18Fluoro-deoxy-glucose positron emission computerized tomography (PET-CT) as alternative first-line diagnostic investigation in suspected recurrence was evaluated. A retrospective study of patients with suspicious fiber-optic findings at more than 12 weeks after LPP. Sensitivity, specificity, and the negative predictive value (NPV) of DL and PET-CT were compared. Seventy-two patients presenting 105 cases of suspicious events were included in this study. Fifty-two events were initially investigated by DL and 53 events by PET-CT. The sensitivity of DL and PET-CT was 56.25% and 100%, respectively. The NPV was 84% for DL and 100% for PET-CT (p=0.015). Negative PET scans after LPP are highly accurate in ruling out recurrent/persistent disease and may spare the patient from negative biopsies.

Prognostic Utility of (18)F-Fluciclovine Positron Emission Tomography (FACBC) in Biochemically Recurrent (BCR) Prostate Cancer (PCa) Treated with Salvage Radiotherapy

<h3>Purpose/Objective(s)</h3> Patients with a biochemical recurrence after definitive radiotherapy or prostatectomy often undergo imaging to localize recurrent disease prior to salvage treatment. FACBC is a commonly utilized scan for this, but little is known about the prognostic utility of imaging metrics derived from FACBC scans in this setting. <h3>Materials/Methods</h3> This single-center retrospective study included 167 patients (pts) who had FACBC for BCR between 10/2017-10/2019. Clinical, pathological, imaging, and treatment data were collected by chart review. Pts who received salvage radiotherapy (SRT) were then identified and classified by whether their scan was positive or negative. Imaging metrics derived from positive scans included maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion metabolism (TLM). Freedom from biochemical progression (FFBP) and overall survival (OS) were compared between pts with positive and negative scans according to the Kaplan-Meier method, and for the above imaging metrics dividing each metric by its median value. Cox regression analysis for the following covariates was also performed: number of recurrence sites, SUVmax, MTV, and TLM. <h3>Results</h3> 71 pts received SRT; 34 had positive scans. The median FFBP for all patients who received SRT was 130 weeks (range 58.4-244.9). There was a statistical difference in FFBP between patients with negative and positive scans (median 130 vs. 128 weeks, p=0.039), but no difference in OS (median 130 vs. 146 weeks, p = 0.140). Among pts with positive scans, there was no difference in FFBP when considering high vs. low SUVmax, MTV, or TLF. There was also no difference when these factors were analyzed via cox regression. <h3>Conclusion</h3> In this retrospective cohort of 71 pts with FACBC PET scans treated with SRT, pts with a negative FACBC had a longer time to biochemical progression, but this did not affect overall survival. Although SUVmax, MTV, and TLM have been shown to be prognostic in other cancers with other PET tracers, none were prognostic in this cohort.

Initial Post-Therapy Imaging as a Predictor of Local Relapse after Radiotherapy in Pediatric Sarcomas

<h3>Purpose/Objective(s)</h3> To assess the value of initial post-therapy scans for predicting local relapse in patients with Ewing sarcoma (EWS) and rhabdomyosarcoma (RMS) who received radiotherapy (RT) for local control. <h3>Materials/Methods</h3> This single-center study included all patients who were diagnosed with EWS or RMS at <22 years of age, completed RT for local control and underwent post-treatment diagnostic imaging evaluations from 2007-2020. Radiologists' impressions of the primary tumor site were categorized as "positive" (residual disease within RT field), "negative" (no residual disease within RT field), or "equivocal." Each patient was assigned to one of these categories, based on the radiologists' overall impression of all off-therapy scans. The primary endpoint was local progression (LP), defined as disease progression within the RT field. Positive predictive value (PPV) and negative predictive value (NPV) quantified the ability of off-therapy imaging studies to predict LP. Actuarial rates of LP were calculated using Kaplan-Meier methods. <h3>Results</h3> Sixty-eight patients were eligible (29 EWS, 39 RMS). The median age at diagnosis was 8 years (range 0-21). All patients received chemotherapy and RT based on disease histology and risk group, per Children's Oncology Group protocols. RT was to a median dose of 50.4 Gy (range 36-55.8); 19 patients (28%) underwent surgery and RT for local control, and 49 (72%) received RT alone. Post-treatment imaging was performed 3 weeks (range <1- 13) after completion of chemotherapy and 17 weeks (range 4-52) after completion of RT. Post-treatment imaging of the primary site included PET in 51 patients (75%), MRI in 54 (79%), and CT in 5 (7%). Radiologists' overall impressions were that 1 patient's (1%) scans were positive, 50 (74%) were negative, and 17 (25%) were equivocal. 4-year LP was 100% for patients with positive scans, 12% for patients with negative scans, and 5.9% for patients with equivocal scans. The difference in the percentages of LP for patients with negative vs. equivocal scans did not reach significance (p= 0.5). Positive scans had a PPV of 100%, and negative scans an NPV of 88%. When equivocal results were considered positive (positive/equivocal vs. negative), the PPV was 11%. When equivocal results were considered negative (positive vs. equivocal/negative), the NPV was 90%. Five patients (29%) with equivocal results underwent short-term surveillance imaging at a median of 7 weeks (range 6-9) after the equivocal studies. No short-term follow-up scan demonstrated local progression. <h3>Conclusion</h3> Equivocal findings on initial post-treatment diagnostic imaging studies did not indicate a higher risk of local recurrence after RT than negative findings. These results may influence the interpretation of initial post-therapy scans and contribute to accurate counseling of patients and families.

A Pilot Study of Salvage HDR Brachytherapy in Recurrent Prostate Cancer: 5 Year Toxicity and Outcomes

<h3>Purpose/Objective(s)</h3> Until recently, Androgen Deprivation Therapy (ADT) was the main treatment option for recurrent prostate cancer after primary radiation treatment. However, ADT is not curative and is associated with several side effects. Local ablative therapy can be curative and reduce long-term side effects associated with ADT. We designed a single institution prospective pilot study to evaluate the toxicities and outcomes of HDR brachytherapy as a salvage local therapy. <h3>Materials/Methods</h3> Sixty (60) patients with a biopsy-proven local relapse after a previous treatment with radiation were included in this study. A negative bone scan and CT scan of the abdomen and pelvis at the time of relapse was mandatory. Primary objective was to assess both early and late genitourinary (GU) and gastrointestinal (GI) toxicities. Biochemical disease-free survival (bDFS) was also assessed as a secondary objective. Toxicities were reported using CTCAE v5 scale and the IPSS. Short-course ADT could be used if deemed clinically indicated by the physician. HDR brachytherapy regimen was 32Gy delivered in 4 fractions to the whole prostate and, for the last 10 patients recruited, 27Gy in 2 fractions administered focally, due to concerns with toxicities. CT-based treatment planning using an inverse planning algorithm (IPSA) was performed for patients with whole prostate treatment (n = 50). Real-time ultrasound-based treatment planning was used for patients undergoing focal salvage radiation (n = 10). <h3>Results</h3> Median follow-up was 58.4 months (0.8-106.8 months). GI toxicities were acceptable with 3.6% and 14.5% of patients experiencing early and late grade 2 toxicities. No G3 GI toxicities were reported. Early G2 GU toxicities were overestimated at 100% (all patients used an alpha-blocker in the postoperative setting) and one patient had G3 early toxicity. Late GU toxicities were significant, with 14.5% of patients experiencing late G3 toxicity (10.0% at the last follow-up). Of interest, the use of ADT before HDR brachytherapy (n = 17) was associated with lower GU toxicities (no G3) although the association was not statistically significant (Chi-Square p-value 0.201). Good biochemical control was achieved with a bDFS of 73.9% at 48 months. <h3>Conclusion</h3> Salvage HDR brachytherapy after primary radiation to the prostate offers good biochemical control but at the cost of significant G3 GU morbidities. Patients can benefit from local therapy after primary radiation but whole-gland radiation should be used with caution because of concern with toxicities. Focal therapy to partial gland might be a good alternative to achieve local control and avoid severe toxicities.

Who should be referred for a CT coronary calcium score? Introducing a simple patient risk questionnaire combining traditional and novel risk factors.

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of death. Coronary artery calcium (CAC) strongly predicts the risk of ASCVD. There is a need to know who would benefit most from CAC scanning. We examined the utility of a new, simple, easy-to-use, and interactive patient risk questionnaire (PRQ), incorporating both traditional and non-traditional risk factors to identify those most likely to benefit from CAC scanning. Data from the EISNER Study was used to study the PRQ in relation to the extent of CAC and whether it added incremental value over the Pooled Cohort Risk Score (PCRS) for identifying CAC. Among 1332 participants a mean PRQ score of 5.6 ± 1.7 was obtained. Negative scans ranged from 95.5% for PRQ scores of 0-1 to only 32.5% for those with a PRQ score of 8. A PRQ score of 3 or more was shown to be associated with a 54% prevalence of CAC. The frequency of a CAC score >=100 was 0 with PRQ = 0-1 and 36% in patients with PRQ = 8. The cNRI of the PRQ score over the PCRS in predicting the presence of CAC was 0.20 (95% CI, 0.09- 0.30; P = 0.0004), mainly due to down-stratifying risk. A unique and simple PRQ identifies those most likely to have a positive CAC scan and may be useful to predict who will benefit most from CAC scanning, allowing for its use in those patients who are most appropriate.

Posttherapy technetium-99m pentavalent dimercaptosuccinic acid brain single-photon emission computed tomography/computed tomography: diagnostic and prognostic values in patients with glioma.

To assess the value of posttherapy 99mTc-pentavalent dimercaptosuccinic acid (DMSA-V) brain SPECT/CT in patients with brain glioma. Patients with pathologically or radiologically proven glioma were prospectively enrolled in this study. 99mTc-DMSA-V brain SPECT/CT images were acquired at 120-180 min after i.v. injection of 555-740 MBq of 99mTc-DMSA-V. Three nuclear medicine physicians blindly interpreted the scans visually as positive or negative for residual/recurrent disease. Agreement between two or more readers was considered a consensus. The composite reference standard was considered based on subsequent clinical/neuroimaging follow-up or histopathology whenever available. Overall survival (OS) was calculated from the date of initial diagnosis till the death or the date of last follow-up. Thirty-four patients (18 males and 16 females; mean age 37.7 ± 16 years) were enrolled in this study. Interreader agreement between the readers ranged from 0.71 to 0.82. Based on the composite reference standard, residual/recurrent disease was confirmed in 16 patients, whereas 18 patients were negative for disease. Consensus reading of 99mTc-DMSA-V SPECT/CT accurately diagnosed 13 true positive (sensitivity 81%) and 17 true negative scans (specificity 94%). After a median follow-up of 22.9 months, 7/14 patients with positive 99mTc-DMSA-V SPECT/CT brain readings died compared to 4/20 with negative readings. The median survival was 24.1 months for the positive group and was not reached for the negative group. Posttherapy brain SPECT/CT scanning with 99mTc-DMSA-V is a noninvasive, reliable, and specific tool for evaluation of patients with brain glioma after definitive therapy. Scan positivity was associated with poor OS.

Locoregional therapy for oligometastatic cervical cancer: a single-center retrospective study

BackgroundOligometastases are limited in number and extent, and therefore, are amenable to locoregional therapy.ObjectiveTo analyze recurrence patterns, survival outcomes, and prognostic factors in patients with cervical cancer receiving locoregional therapy...

Evaluation of [68 Ga]Ga-PSMA-I&T PET/CT with additional late scans of the pelvis in prostate-specific antigen recurrence using the PROMISE criteria

BackgroundPSMA PET/CT is the recommended imaging test in cases with prostate-specific antigen (PSA) recurrence after primary therapy of prostate cancer (PCa). However, imaging protocols remain a topic of active research. The aim of the presented study was to examine the impact of additional late scans of the pelvis in [68 Ga]Ga-PSMA-I&T PET/CT of patients with rising PSA after prostatectomy.MethodsA total of 297 patients (median PSA 0.35 ng/ml, interquartile range (IQR) 0.2–0.8) who underwent early whole-body [68 Ga]Ga-PSMA-I&T PET/CT (median dose 141 MBq, IQR 120–163; median 86 min, IQR 56–107) and additional late scans of the pelvis (median 180 min, IQR 170–191) were investigated retrospectively. Early and late images were staged separately according to the PROMISE criteria and compared with a final consensus of both. Standardized uptake values were analyzed for early and late scans.ResultsOne hundred and thirty-four (45.1%) [68 Ga]Ga-PSMA-I&T PET/CT showed evidence of recurrent PCa (114/38.4% early, 131/44.1% late). Of 195 lesions, 144 (73.8%) were identified correctly on early scans. 191 (97.9%) lesions were detected on late imaging. The lesion SUVmax (median 3.4, IQR 0.4–6.5 vs. median 3.9, IQR 2.6–8.2) as well as the SUVmax to background ratio (median 9.4, IQR 1.7–19.1 vs. median 15.5, IQR 9.6–34.1) increased significantly between the imaging time points (p < 0.01, respectively). Compared to the final consensus, the miTNM-staging of early scans changed in 58 (19.5%) cases. Of these, 31 patients (10.4%) with negative early scans (T0 N0 M0) were upstaged. Twenty-seven (9.1%) patients with PCa characteristic lesions on early imaging (> T0 N0 M0) were up- and/or downstaged. In 4 (1.3%) cases, PCa-related lesions were only detectable on early PET/CT leading to upstagings of late imaging.ConclusionsAdditional late scans of the pelvis in [68 Ga]Ga-PSMA-I&T PET/CT detected more lesions and an increasing contrast compared to early imaging. This influenced the final miTNM-staging substantially.

Clinical impact of amyloid PET using 18F-florbetapir in patients with cognitive impairment and suspected Alzheimer’s disease: a multicenter study

ObjectiveAmyloid positron emission tomography (PET) can reliably detect senile plaques and fluorinated ligands are approved for clinical use. However, the clinical impact of amyloid PET imaging is still under investigation. The aim of this study was to evaluate the diagnostic impact and clinical utility in patient management of amyloid PET using 18F-florbetapir in patients with cognitive impairment and suspected Alzheimer’s disease (AD). We also aimed to determine the cutoffs for amyloid positivity for quantitative measures by investigating the agreement between quantitative and visual assessments.MethodsNinety-nine patients suspected of having AD underwent 18F-florbetapir PET at five institutions. Site-specialized physicians provided a diagnosis of AD or non-AD with a percentage estimate of their confidence and their plan for patient management in terms of medication, prescription dosage, additional diagnostic tests, and care planning both before and after receiving the amyloid imaging results. A PET image for each patient was visually assessed and dichotomously rated as either amyloid-positive or amyloid-negative by four board-certified nuclear medicine physicians. The PET images were also quantitatively analyzed using the standardized uptake value ratio (SUVR) and Centiloid (CL) scale.ResultsVisual interpretation obtained 48 positive and 51 negative PET scans. The amyloid PET results changed the AD and non-AD diagnosis in 39 of 99 patients (39.3%). The change rates of 26 of the 54 patients (48.1%) with a pre-scan AD diagnosis were significantly higher than those of 13 of the 45 patients with a pre-scan non-AD diagnosis (χ2 = 5.334, p = 0.0209). Amyloid PET results also resulted in at least one change to the patient management plan in 42 patients (42%), mainly medication (20 patients, 20%) and care planning (25 patients, 25%). Receiver-operating characteristic analysis determined the best agreement of the quantitative assessments and visual interpretation of PET scans to have an area under the curve of 0.993 at an SUVR of 1.19 and CL of 25.9.ConclusionAmyloid PET using 18F-florbetapir PET had a substantial clinical impact on AD and non-AD diagnosis and on patient management by enhancing diagnostic confidence. In addition, the quantitative measures may improve the visual interpretation of amyloid positivity.

Racial and Ethnic Differences in Amyloid PET Positivity in Individuals With Mild Cognitive Impairment or Dementia

Racial and ethnic groups with higher rates of clinical Alzheimer disease (AD) are underrepresented in studies of AD biomarkers, including amyloid positron emission tomography (PET). To compare amyloid PET positivity among a diverse cohort of individuals with mild cognitive impairment (MCI) or dementia. Secondary analysis of the Imaging Dementia-Evidence for Amyloid Scanning (IDEAS), a single-arm multisite cohort study of Medicare beneficiaries who met appropriate-use criteria for amyloid PET imaging between February 2016 and September 2017 with follow-up through January 2018. Data were analyzed between April 2020 and January 2022. This study used 2 approaches: the McNemar test to compare amyloid PET positivity proportions between matched racial and ethnic groups and multivariable logistic regression to assess the odds of having a positive amyloid PET scan. IDEAS enrolled participants at 595 US dementia specialist practices. A total of 21 949 were enrolled and 4842 (22%) were excluded from the present analysis due to protocol violations, not receiving an amyloid PET scan, not having a positive or negative scan, or because of small numbers in some subgroups. In the IDEAS study, participants underwent a single amyloid PET scan. The main outcomes were amyloid PET positivity proportions and odds. Data from 17 107 individuals (321 Asian, 635 Black, 829 Hispanic, and 15 322 White) with MCI or dementia and amyloid PET were analyzed between April 2020 and January 2022. The median (range) age of participants was 75 (65-105) years; 8769 participants (51.3%) were female and 8338 (48.7%) were male. In the optimal 1:1 matching analysis (n = 3154), White participants had a greater proportion of positive amyloid PET scans compared with Asian participants (181 of 313; 57.8%; 95% CI, 52.3-63.2 vs 142 of 313; 45.4%; 95% CI, 39.9-50.9, respectively; P = .001) and Hispanic participants (482 of 780; 61.8%; 95% CI, 58.3-65.1 vs 425 of 780; 54.5%; 95% CI, 51.0-58.0, respectively; P = .003) but not Black participants (359 of 615; 58.4%; 95% CI, 54.4-62.2 vs 333 of 615; 54.1%; 95% CI, 50.2-58.0, respectively; P = .13). In the adjusted model, the odds of having a positive amyloid PET scan were lower for Asian participants (odds ratio [OR], 0.47; 95% CI, 0.37-0.59; P < .001), Black participants (OR, 0.71; 95% CI, 0.60-0.84; P < .001), and Hispanic participants (OR, 0.68; 95% CI, 0.59-0.79; P < .001) compared with White participants. Racial and ethnic differences found in amyloid PET positivity among individuals with MCI and dementia in this study may indicate differences in underlying etiology of cognitive impairment and guide future treatment and prevention approaches.

P041: Low percentage of T lymphocytes in Hodgkin’s Lymphoma lymph nodes, measured by flow cytometry, is associated with inferior progression free survival regardless of negative interim pet scan status

Figure 1: Kaplan-Meier estimates of progression free survival stratified according to T-lymphocyte percentage in lymph node biopsies in Hodgkin lymphoma Background: Tumor microenvironment (TME) can influence antitumor immunity and survival in Hodgkin lymphoma (HL) as previously published. However, most of this data has sparse clinical applicability. Flow cytometry (FC) has limited utility in HL diagnosis but its potential to assess TME has not been fully explored yet. Aims: To determine the prognostic impact on survival of the percentage (%) of tumor infiltrating lymphocytes (TIL) and CD4/CD8 ratio in lymph nodes (LN) measured by FC. Methods: We selected patients (pts) with HL, available LN FC data at diagnosis and i-PET scan, treated at our center from 2012–2020. FC was performed with 8-color panels according to Euroflow protocols. TIL % and CD4/CD8 ratio in LN by FC were compared to normal values reported (Battaglia, Immunology 2003) and stratified as low, normal and high. Response was assessed per Lugano recommendations. Progression free survival (PFS) was estimated with Kaplan-Meier, multivariate analysis with Cox regression, and variables were compared with log-rank test. Results: 46 pts were included. Median age: 34 years. 24/27 with early stage had unfavorable risk and 11/19 with advanced disease had IPS≥3. 95% received ABVD. Complete response rate was 91.3%. 2 pts died. Median PFS: not reached (NR), 75th percentile 43 months (m), and median follow up: 49 m. i-PET negative (neg) pts had significantly better PFS (median NR vs 13.7 m in i-PET positive subgroup, p:0.014). Low LN TIL % was associated with inferior PFS (median 24.4 m vs. NR in pts with normal or high TIL, p:0.024). Regarding CD4/CD8 ratio, PFS rates were 100%, 75% and 60% in normal, low and high subgroups respectively, p:0.041. Both low TIL and positive i-PET remained independent predictors of survival on multivariate analysis with HR of 11.8 (CI 95% 1.9–72.7, p:0.021), and 7.7 (CI 95% 1.6–36.4, p:0.01) respectively. LN TIL % could further stratify outcomes in pts with neg i-PET scans. In this subset, pts with low TIL had a median PFS of 24.4 m and PFS rates of 33.3% vs. median NR in normal and high subgroups and PFS rates of 88.9 and 87.5% respectively, p:0.006. Conclusions: LN TIL % measured by FC showed prognostic impact in our cohort of HL pts. Pts with low TIL had inferior PFS, even in those with optimal interim response where the median was only 2 years. This finding denotes the critical role of T cells to achieve cure. Checkpoint blockade might constitute an appealing approach in these pts to restore effective antitumor immunity.

AML-139 Early Onset of Therapy-Related Acute Myeloid Leukemia in a Patient Treated for a Hodgkin Lymphoma

Therapy-related acute myeloid leukemia (t-AML) is a known complication of certain types of therapies, such as cytotoxic, radiation, or immunosuppressants. At present, t-AML incidence is relatively low. However, this is expected to change in the near and medium future due to improved overall survival rates. t-AML can occur a few months to several years after the initial therapy, depending on the type and dosage of therapy and patient-specific variation. The prognosis is generally poor, with patients presenting complex karyotype and significant structural abnormalities. As such, the optimal treatment remains a challenge. We report the case of a patient treated for a Hodgkin lymphoma stage IIB in December 2019, who underwent 8 cycles of ABVD and radiotherapy 30 Gy with a negative PET scan in August 2020, diagnosed with acute monoblastic leukemia (M5a - FAB) in January 2021. A 53-year-old male, smoker, presented with fatigue and oliguria for the past month. Laboratory studies revealed leukocytosis (272×109/L), thrombocytopenia (83×109/L) and no anemia, with 90% blasts in peripheral blood smear. The metabolic profile revealed a tumoral lysis syndrome and an elevated lactate dehydrogenase of 1877 U/L. The bone marrow aspirate showed 98-99% blasts cells of monocytic lineage while the flow cytometry analysis indicated 95% monocytic cells, positive for CD64+, CD33++, CD56+, CD36+ slab, CD300e-, CD14-, HLA-DR+. Normal karyotype, negative FISH for del 17p - TP53, and negative for the tested genes on RT-PCR (FLT3, RUNX1-RUNX1T1, CBFb-MYH11, MLL-AF9, PML-RARA), NGS negative (blood specimen). The patient had been successfully treated with conventional chemotherapy and underwent bone marrow transplantation from an unrelated donor with 100% donor chimerism at one year. t-AML only rarely presents with normal karyotype and there is a lack of clearly defined prognostic factors. Optimal treatment is still very much a matter of debate, in part because of the poor prognosis of the condition, and the only treatment with curative intent remains allogeneic hematopoietic stem cell transplantation.

S2472 A Case of Functional Bowel Disease Misdiagnosed as Carcinoid Syndrome

Introduction: Carcinoid tumor is a well-differentiated neuroendocrine tumor (NET) that arises from enterochromaffin cells. NETs produce serotonin which is metabolized to the inactive 5-hydroxyindoleacetic acid (5-HIAA) by the liver and the lungs. Carcinoid syndrome results from the secretion of serotonin into the systemic circulation by a metastatic NET that originates from the midgut. The primary screening method for carcinoid syndrome is 24-hour urinary 5-HIAA (U-5HIAA) which has a 90 percent sensitivity and specificity in diagnosing carcinoid syndrome. This case illustrates a unique scenario of a markedly elevated U-5HIAA not due to NET. Case Description/Methods: A 29-year-old female presented to our clinic with abdominal pain, bloating, diarrhea, and weight loss associated with postprandial facial flushing. Medications included Dextroamphetamine and Fremanezumab. Based on her symptoms, U-5HIAA was ordered and was elevated at 148 mg (normal < 6). Carcinoid Syndrome was suspected based on symptoms and markedly elevated U-5HIAA. Imaging studies were ordered to identify primary or metastatic NET. These included negative CT abdomen/pelvis and a negative Ga68 Dotatate NETSPOT PET scan. Upper endoscopy and Colonoscopy were also negative. The patient expressed difficulty in stopping dextroamphetamine for the urine collection but due to the negative evaluation for NET she finally agreed to hold it for 3 days. Repeat U-5HIAA decreased down to 10.4 mg. Her symptoms were then believed to be secondary to functional bowel disease. The patient’s symptoms improved with mirtazapine and dicyclomine, and she regained the weight. Discussion: This is a unique case with a misleading U-5HIAA. While mildly elevated levels of U-5HIAA can be seen with tryptophan rich foods and certain drugs, including amphetamines, marked elevation, like in our case is more specific and usually seen with the carcinoid syndrome. Our patient had symptoms suspicious of carcinoid syndrome and a U-5HIAA of 148 mg, which is 25 times the upper normal. However, there was no evidence for NET on extensive work up, and the levels rapidly decreased with stopping dextroamphetamine. To our knowledge, this is the highest falsely positive U-5HIAA reported. This case shows the importance of a complete drug history, including over-the-counter medications. When the 5-HIAA is elevated, the test needs to be repeated after discontinuing all potentially interfering medications.