Positron Emission Tomography-computed Tomography Results Research Articles

Pre-malignant conditions diagnosed following a positive cancer signal from a multi-cancer early detection test.

Blood-based tests for multi-cancer early detection (MCED) are being developed to facilitate the detection of various cancer types. The Detecting cancers Earlier Through Elective mutation-based blood Collection and Testing study (DETECT-A) study evaluated an MCED test in 9,911 women, age 65-75, without personal history of cancer. In a post-hoc analysis, we report on the detection of precancerous neoplasms consequent to MCED testing and follow-up. Participants with positive baseline and confirmatory MCED testing underwent 2-deoxy-2[fluorine-18] fluoro-D-glucose positron emission tomography-computed tomography (PET-CT) and diagnostic evaluation as indicated by PET-CT results. We reviewed the electronic health records of participants with a precancerous neoplasm and summarized their clinical course. MCED results were positive in 134 participants. Clinically significant pre-malignant conditions were identified in three of these participants: A 71-year-old with an ovarian mucinous cystadenoma, a 67-year-old with an appendiceal mucinous neoplasm, and a 70-year-old with colon adenomas displaying high-grade dysplasia. All three participants underwent surgical treatment and remain alive and cancer-free as of last follow up. The diagnostic evaluation of a positive MCED test may occasionally reveal clinically significant pre-cancerous conditions amenable to interventions. The frequency of such findings and their clinical impact warrants further study.

Transport and spatio-temporal conversion of sugar facilitate the formation of spatial gradients of starch in wheat caryopses

Wheat grain starch content displays large variations within different pearling fractions, which affecting the processing quality of corresponding flour, while the underlying mechanism on starch gradient formation is unclear. Here, we show that wheat caryopses acquire sugar through the transfer of cells (TCs), inner endosperm (IE), outer endosperm (OE), and finally aleurone (AL) via micro positron emission tomography-computed tomography (PET-CT). To obtain integrated information on spatial transcript distributions, developing caryopses are laser microdissected into AL, OE, IE, and TC. Most genes encoding carbohydrate transporters are upregulated or specifically expressed, and sugar metabolites are more highly enriched in the TC group than in the AL group, in line with the PET-CT results. Genes encoding enzymes in sucrose metabolism, such as sucrose synthase, beta-fructofuranosidase, glucose-1-phosphate adenylyltransferase show significantly lower expression in AL than in OE and IE, indicating that substrate supply is crucial for the formation of starch gradients. Furthermore, the low expressions of gene encoding starch synthase contribute to low starch content in AL. Our results imply that transcriptional regulation represents an important means of impacting starch distribution in wheat grains and suggests breeding targets for enhancing specially pearled wheat with higher quality.

Guiding function of positron emission tomography-computed tomography examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma.

To explore the role of positron emission tomography-computed tomography (PET-CT) examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma (OAML). The general clinical data, postoperative PET-CT results, treatment regimens, and the prognosis of 21 histopathologically confirmed OAML patients between October 2017 and September 2021 were collected. Among the 21 patients, five patients underwent surgical treatment alone, 13 patients underwent surgical treatment combined with radiotherapy, and three patients underwent surgical treatment combined with chemotherapy. The follow-up period ranged from 8 to 79mo, with four cases of recurrence and no deaths. Through PET-CT examination, two patients exhibited both local ocular metabolic elevation and systemic metastasis, and one of these patients had cervical lymph node metastasis, while the other had submandibular and parotid gland metastasis. Nine patients showed only local ocular metabolic elevation, while 10 patients had no abnormal metabolic activity locally. PET-CT examination plays a crucial role in detecting residual lesions and recurrence following tumor resection, aiding in precise disease staging, and facilitating the development of personalized treatment plans, ultimately improving patient prognosis.

Clinical predictors and implications of cardiac inflammation detected on positron emission tomography (PET) in patients referred for premature ventricular complex (PVC) ablation.

Positron emission tomography computed tomography (PET-CT) is not routinely used for premature ventricular complexes (PVCs). Whether specific clinical factors are associated with abnormal PET-CT results is not clear. The treatment courses and baseline characteristics of consecutive patients in a single center between 2012 and 2021, age > 18years old, and who received 18F-fluorodeoxyglucose (FDG) PET-CT imaging for evaluation of PVCs were retrospectively analyzed. A total of 102 patients was included. Of these, 27 patients (26.4%) had abnormal PET-CT and 61 (59.8%) had normal imaging. Abnormal PET-CT findings were associated with non-sustained ventricular tachycardia (NSVT) (95.2% vs. 52.6%, p = 0.001), higher number of PVC morphologies (2.29 ± 0.7 vs. 1.31 ± 0.6, p < 0.001), greater PVC coupling interval dispersion (72.47 ± 66.4ms vs. 13.42 ± 17.9ms, p < 0.001), and greater likelihood of fast heart rate dependent PVCs (78.5% vs. 38.2%, p = 0.017). Fourteen (51.8%) patients had an abnormal PET-CT and abnormal late gadolinium enhancement (LGE). Patients with abnormal PET-CT were more frequently treated with immunosuppression (81.4% vs. 3.2%, p < .0001) than with catheter ablation (11.1% vs. 45.9%, p = 0.002) compared to the normal PET-CT group. Over a median follow-up of 862days (IQR 134, 1407), PVC burden decreased in both groups [from 23 ± 16% to 9 ± 10% (p < 0.001) in abnormal PET-CT group and from 21 ± 15% to 7 ± 10% (p < 0.001) in normal PET-CT group]. Abnormal PET-CT findings were more commonly associated with NSVT, multiform PVCs, greater PVC coupling interval dispersion, and fast heart rate dependent PVCs. LGE was not sensitive for detecting inflammation. Immunosuppression was effective in managing PVCs with abnormal PET-CT.

PSMA PET-CT Imaging Predicts Treatment Progression in Men with Biochemically Recurrent Prostate Cancer-A Prospective Study of Men with 3 Year Follow Up.

Simple SummaryProstate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) is an essential imaging tool that is used to locate prostate cancer when it recurs. The results of this scan are used to guide clinical decisions for the management of cancer. However, the long-term effect of these clinical decisions is yet to be determined. In this study, we followed men with recurrent prostate cancer for 3 years after they had a clinical decision made based on a PSMA PET-CT. Our results showed that 75% of men had no addition or change in their treatment plan 3 years after their initial clinical decision was made. In men with a PSMA PET-CT that showed no suspected cancer, 85% had no addition or change to their treatment plan. This indicates that clinical decisions made using PSMA PET-CT in this setting can have a medium- to long-lasting effect.Prostate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) is a novel imaging modality used to stage recurrent prostate cancer. It has the potential to improve prognostication and ultimately guide the timing of treatment for men with recurrent prostate cancer. This study aims to assess the clinical impact of PSMA PET-CT by analyzing its predictive value of treatment progression after 3 years of follow-up. In this prospective cohort study of 100 men, patients received a PSMA PET-CT for restaging of their disease which was used by a multi-disciplinary team to make a treatment decision. The primary endpoint was treatment progression. This was defined as the addition or change of any treatment modalities such as androgen deprivation therapy (ADT), radiation therapy or chemotherapy. The median follow-up time was 36 months (IQR 24–40 months). No treatment progression was found in 72 (75%) men and therefore 24 (25%) patients were found to have treatment progression. In men with a negative PSMA PET-CT result, 5/33 (15.1%) had treatment progression and 28/33 (84.8%) had no treatment progression. In conclusion, clinical decisions made with PSMA PET-CT results led to 75% of men having no treatment progression at 3 years of follow-up. In men with negative PSMA PET-CT results, this increased to 85% of men.

IPET-CT in inflammatory diseases of kidneys and bladder: diagnostic efficacy

Introduction. The incorporation of combined positron emission tomography-computed tomography (PET-CT) into clinical practice has significantly expanded the understanding of the pathogenesis of many diseases. Evidence-based data on the diagnostic efficacy in infectious and inflammatory diseases is increasing, making this imaging method very promising. Purpose of the study. To study the diagnostic efficacy of 18F-FDG PET-CT in various chronic inflammatory diseases of kidneys and bladder.Materials and methods. A retrospective study of the results of whole-body 18F-FDG PET-CT in 45 patients was carried out. Patients underwent an investigation at various times after surgical treatment of localized oncology of the anogenital zone at the T1N0M0 stage without the involvement of the genitourinary system. It was found that 24 patients had a history of chronic pyelonephritis and 21 patients had manifestations of radiation cystitis. Repeated PET/CT scans were performed after a course of therapy for inflammatory urological diseases to assess the treatment results of the underlying pathology.Results. The latent course of chronic renal failure was accompanied by a diffuse decrease in 18F-FDG metabolism in the renal parenchyma with its partial recovery after etiotropic therapy and urine sanitation. Hypermetabolism of 18F-FDG was detected in the bladder wall during manifestations of radiation cystitis, which was leveled during therapy and relief of urinary syndrome manifestations. Bacterial and radiation inflammation differed in molecular-cell responses to the pathogen, while the results of urinalysis, indicating the effectiveness of the treatment, coincided with the visual and digital indicators of the restoration of adequate energy metabolism in the studied tissues.Conclusions. Metabolism of 18F-FDG in the kidneys and bladder can objectively reflect the nature of inflammation and complement the data on the effectiveness of the treatment.

Performance of Dual-tracer PET-CT for Staging Post-Liver Transplant Hepatocellular Carcinoma Recurrence.

Background.Precise staging is essential in the management of patients with recurrent hepatocellular carcinoma (HCC) after liver transplantation. There is no current consensus on the optimal staging strategy. We conducted this study to evaluate the performance of dual-tracer positron emission tomography-computed tomography (PET-CT) for this purpose and to investigate whether the results of dual-tracer PET-CT affected patient management.Methods.A retrospective study was conducted. Patients who underwent dual-tracer PET-CT for suspected or confirmed HCC recurrence after liver transplant were included. The lesion-based sensitivity and positive predictive value of dual-tracer PET-CT were determined.Results.Fifty-six patients and 189 recurrent tumors were included. The lesion-based sensitivity and positive predictive value of dual-tracer PET-CT were 94.7% and 90.4%, respectively. The sensitivity of dual-tracer PET-CT was better than the standard imaging in the surveillance protocol (82.5% versus 94.7%, P < 0.001), especially for detecting liver recurrence (71.0% versus 96.8%, P < 0.001). Half of the dual-tracer PET-CT detected additional recurrence (n = 26, 46.4%) and one-third led to a change in management (n = 19, 33.9%). Ten patients (17.9%) with inconclusive standard imaging had metabolic recurrence confirmed on PET-CT and treatment was commenced early. Four patients (7.1%) had revised locoregional treatment, and 5 (8.9%) had to withdraw from locoregional treatment after the detection of additional metastatic disease.Conclusions.Dual-tracer PET-CT is effective for staging posttransplant HCC recurrence. It often provides valuable information to guide clinical management.

Features of Spinal Metastases: A Retrospective View.

The present study aimed to determine the frequency of spinal metastases, to evaluate the features of spinal metastases, and to reveal clues to shed light on the origin of spinal metastases with unknown primary. The data of patients who were followed up with the diagnosis of cancer in Istanbul Oncology Hospital between 2017 and 2019 were analyzed retrospectively. A total of 156 patients with spinal metastases and without visceral metastases were included in the study by applying inclusion and exclusion criteria. Clinical data, pathological diagnostic reports, and positron emission tomography-computed tomography results of 156 patients were evaluated. The groups were evaluated in terms of age, gender, number of spinal metastases (single focus, multiple focus), and localization of spinal metastasis. The spinal localization evaluation included both the main anatomical localizations and a detailed evaluation of each spine. The most common metastasis region was the thoracic spine in respiratory system cancers (28.38%), the thoracic + lumbar spine in breast (42.42%), prostate (50.00%), and gynecologic (40.00%) cancers, and the lumbar spine in gastrointestinal (37.50%) and urinary (30.00%) tract cancers (P = .313). C5 spinal metastasis percentages were significantly higher in breast and gastrointestinal tract cancers than the others (P = .042). T5 spinal metastasis percentage was significantly higher in gynecologic tumors than in the other cancers (P = .002). T10 spinal metastasis percentages were significantly higher in prostate and gynecologic tumors than the others (P = .016). L1 spinal metastasis percentage was significantly higher in breast tumors (P = .009). L2 spinal metastasis percentages were significantly higher in breast, prostate, and gynecologic tumors (P = .011). L4 spinal metastasis percentages were significantly higher in breast and prostate tumors (P = .041). L5 spinal metastasis percentage was significantly higher in prostate tumors (P = .029) than the other cancers. It was observed that primary cancers were often prone to metastasis to nearby spine. The results obtained by detailed examination of spinal metastases may provide a clinical benefit by providing clues in investigation of primary unknown cancers. 3.

Does prior mediastinal lymph node aspiration contribute to false-positive positron emission tomography-computed tomography?

BackgroundProper staging of the mediastinum is an essential component of lung cancer evaluation. Positron emission tomography–computed tomography (PETCT) and endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) are an integral part of this process. False-positive PETCT results can occur following surgical procedures but has not been demonstrated following EBUS-TBNA. We aimed to determine whether false-positive PETCT rates increase when EBUS-TBNA is performed prior to PETCT.Study design and methodsA retrospective review was carried out of clinical cases that underwent both PETCT and EBUS-TBNA within 30 days for the suspected malignancy. The impact of test sequence on the PETCT false-positive rate (FPR) was determined using Generalised Estimating Equation logistic regression analysis.ResultsA total of 675 lymph node stations were sampled and imaged on PETCT. Overall, 332 (49.2%) nodes were sampled by EBUS-TBNA before PETCT, and 343 (50.8%) afterwards, with the interval between EBUS and subsequent PETCT being a mean±sd of 11.6±6.8 days (range 1–29). The FPR on qualitative PETCT for the EBUS first group was 41 (23.2%) out of 164, and for PETCT first it was 57 (29.0%) out of 193 for a difference of 5.8% (95% CI −3.4–14.7, p=0.22). In the regression model, EBUS as the first test was associated with a lower FPR when using the clinical PETCT interpretation.InterpretationThe performance of EBUS-TBNA sampling did not influence the FPR of PETCT when bronchoscopy took place in the 30 days prior to testing. Test sequence should be selected based on other clinical considerations.

ISY9-1 - Interim PET-CT-adapted treatment for malignant lymphoma

Positron emission tomography-computed tomography (PET-CT) is widely used in the management of malignant lymphoma especially in staging and response assessment at the end of treatment. PET-CT provides more accurate information than conventional imaging studies including computed tomography (CT) and has been incorporated into essential imaging study for staging and response assessment in the recently published criteria (Lugano classification). In patients with advanced stage classic Hodgkin lymphoma (HL), results of interim PET-CT after 1-3 cycles of standard chemotherapy including ABVD have been shown to be predictive for prognosis when the patient continues the same regimen regardless of the result of interim PET-CT. Thus, it would be a reasonable approach to switch therapy to more intensive regimen such as escalated BEACOPP in patients with a positive interim PET-CT or less intensive regimen in patients with a negative result. Clinical trials to evaluate such an interim PET-CT-adapted approach have been conducted for advanced stage HL (SWOG S0816, UK RATHL, GITIL-FIL HD 0607). Results of these studies suggests that interim PET-CT-adapted intensified treatment may improve prognosis of patients with positive interim PET-CT. Moreover, in interim PET-CT-negative patients, omitting bleomycin, potentially pulmonary toxic agent, might be possible without jeopardizing prognosis. There are several challenges in incorporating interim PET-CT-adapted treatment in clinical practice in Japan. For instance, interpretation of PET-CT based on 5-point scale has not been widely accepted among PET-CT specialists. Japan Clinical Oncology Group is conducting a clinical trial (JCOG1305) to confirm the utility of PET-guided treatment strategy for previously untreated advanced stage HL.

Are positron emission tomography-computed tomography (PET-CT) scans useful in preoperative assessment of patients with peritoneal disease before cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC)?

Introduction: CRS and HIPEC confer survival benefit in selected patients with peritoneal metatases (PM). Accurate preoperative assessment of disease burden and exclusion of distant metastases are crucial in selecting the appropriate patient. We evaluate the utility of PET-CT scans in comparison with CT and MRI scans in patients considered for CRS and HIPEC.Methods: Data were retrospectively collected from patients who had been discussed for CRS and HIPEC between January 2011 and December 2015, at our institutional multidisciplinary tumour board. Patients who underwent PET-CT scan were included. Results of PET-CT were compared against traditional imaging. Patient and tumour factors were analysed to identify those who were most likely to benefit from PET imaging.Results: Four hundred and seven patients were considered for CRS and HIPEC. PET-CT was performed for 128(31.4%) patients: being the only imaging modality in 37 and used as an adjunct in 91. In the latter group, it was not beneficial in 58 patients as it provided no additional information (n = 33) or showed lesions of minimal FDG uptake (n = 25). In 33 patients, PET-CT provided definitive answers for indeterminate lesions seen on CT and MRI, confirmed the diagnosis of peritoneal disease in 10 patients (30.3%), identified extra-peritoneal disease and/or nodal metastases in 15 (45.5%) and excluded peritoneal disease in 8 (24.2%). The usefulness of PET-CT was predicted by tumour histology (p = .009), with non-mucinous tumours benefitting the most.Conclusion: Our results suggest that PET-CT can be used as an adjunct to CT and/or MRI scans, when lesions on the CT/MRI scans are indeterminate, and that it is most useful in patients with non-mucinous tumours.

Prospective Evaluation of Magnetic Resonance Imaging and [18F]Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography at Diagnosis and Before Maintenance Therapy in Symptomatic Patients With Multiple Myeloma Included in the IFM/DFCI 2009 Trial: Results of the IMAJEM Study.

Purpose Magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT) are important imaging techniques in multiple myeloma (MM). We conducted a prospective trial in patients with MM aimed at comparing MRI and PET-CT with respect to the detection of bone lesions at diagnosis and the prognostic value of the techniques. Patients and Methods One hundred thirty-four patients received a combination of lenalidomide, bortezomib, and dexamethasone (RVD) with or without autologous stem-cell transplantation, followed by lenalidomide maintenance. PET-CT and MRI were performed at diagnosis, after three cycles of RVD, and before maintenance therapy. The primary end point was the detection of bone lesions at diagnosis by MRI versus PET-CT. Secondary end points included the prognostic impact of MRI and PET-CT regarding progression-free (PFS) and overall survival (OS). Results At diagnosis, MRI results were positive in 127 of 134 patients (95%), and PET-CT results were positive in 122 of 134 patients (91%; P = .33). Normalization of MRI after three cycles of RVD and before maintenance was not predictive of PFS or OS. PET-CT became normal after three cycles of RVD in 32% of the patients with a positive evaluation at baseline, and PFS was improved in this group (30-month PFS, 78.7% v 56.8%, respectively). PET-CT normalization before maintenance was described in 62% of the patients who were positive at baseline. This was associated with better PFS and OS. Extramedullary disease at diagnosis was an independent prognostic factor for PFS and OS, whereas PET-CT normalization before maintenance was an independent prognostic factor for PFS. Conclusion There is no difference in the detection of bone lesions at diagnosis when comparing PET-CT and MRI. PET-CT is a powerful tool to evaluate the prognosis of de novo myeloma.

The Role of PET-CT in Evaluation of Cervical Lymph Node Metastases in Oral Cavity Squamous Cell Carcinomas.

The aim of this study is to determine the sensitivity and specificity of positron emission tomography-computed tomography (PET-CT) in the evaluation of cervical lymph node metastasis in oral cavity squamous cell cancers (SCCs) and to determine the SUV-max values in differentiating reactive and metastatic lymph nodes as a supportive parameter. In this study, 23 patients were included who were diagnosed with oral cavity SCC and treated with surgery between 2006 and 2013 in our department. All the patients were scanned with PET-CT during the pretreatment evaluation. Detailed pretreatment PET-CT (retention sites and SUV-max values) and histopathological examination results were obtained. SPSS 17.0 software package was used for statistical analysis of the data. Categorical measurement was summarized as number and percentage and continuous measurements as mean and standard deviation (median and minimum-maximum where necessary). Chi-square test or Fisher's test were used in the comparison of categorical variables. Compliance of methods was assessed by Kappa coefficient analysis. In this study, the advantages of PET-CT were determined by the calculation of sensitivity and specificity values with histopathological examination results considered as the gold standard, and SUV-max value was assessed by examining the area under the ROC curve. In all tests, the level of statistical significance was accepted as 0.05. The threshold value for SUV-max depending on the data of the histopathological examination and results of PET-CT of the 23 patients was 2.50. The reliability of this threshold was determined as AUC=0.819. In demonstrating neck metastasis in patients with cancer of the oral cavity, PET-CT has a sensitivity of 89% and specificity of 98%. Compliance between the histopathological examination and PET-CT for metastatic cervical lymph nodes was determined to be 0.416 by kappa coefficient analysis. There was FDG uptake on PET-CT in the cervical lymph node regions of all patients with metastatic cervical lymph nodes. There were no metastases in any of the patients with no FDG retention. The sensitivity and specificity of PET-CT in determining cervical lymph node metastasis were 89% and 98%, respectively, with a threshold SUV-max value considered as 2.50 in patients with FDG retention.

FDG PET-CT for lymph node staging of bladder cancer: a prospective study of patients with extended pelvic lymphadenectomy.

The purpose of this study was to evaluate the diagnostic accuracy of [(18)F] fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) for lymph node (LN) staging of bladder cancer patients undergoing radical cystectomy (RC) with extended pelvic lymphadenectomy compared to conventional CT. A total of 61 patients underwent FDG PET-CT before RC and extended pelvic lymphadenectomy. A template for extended pelvic lymphadenectomy to the level of the inferior mesenteric artery was divided into 11 anatomic nodal packets. Definitive pathologic findings of resected LNs were correlated with the results of FDG PET-CT and CT alone in a patient- and nodal packet-based manner. Among the 61 patients, pathological staging confirmed LN metastasis in 17 patients (27.9 %). In total, 627 LN packets (2580 LNs) were resected and histologically evaluated. The mean number of LNs removed was 42 (median 40; range 22-118). Of the 627 LN packets removed, 27 packets (4.3 %) were positive for LN metastasis based on pathologic analysis. On a patient-based analysis, FDG PET-CT and conventional CT showed a sensitivity of 47.1 and 29.4 %, respectively, specificity of 93.2 and 97.7 %, respectively, positive predictive value (PPV) of 72.7 and 78.2 %, respectively, and negative predictive value (NPV) of 82.0 and 78.2 %, respectively. On a nodal packet-based analysis, sensitivity, specificity, PPV, and NPV were 14.8, 97.8, 23.5, and 96.2 %, respectively, for PET-CT and 11.1, 98.7, 27.3, and 96.1 %, respectively, for conventional CT. Combined FDG PET-CT did not improve the diagnostic accuracy of conventional CT for the detection of LN metastasis in bladder cancer patients scheduled for RC.

Clinical Limitations of Surveillance Fluorine 18 Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography According to Histologic Subtypes in Patients with Malignant Lymphoma Who Achieved Complete Remission

Abstract Introduction Fluorine 18 Fluorodeoxyglucose (FDG) Positron emission tomography-computed tomography (PET-CT) scan was highly sensitive modality for evaluating the staging or response of malignant lymphoma. The role of PET to detect early relapse in complete remission was still uncertain. We evaluated the clinical implication of surveillance PET-CT scan in lymphoma patients according to histologic subtype of lymphoma. Patients and methods A total 1009 patients of 1553 treated lymphoma patients, who achieved complete response following primary treatment, were retrospectively reviewed. Among these patients, we analyzed 202 patients who showed positive results of PET-CT and performed tissue biopsy of FDG uptake sites. Results Total 202 surveillance PET-CT positive patients, 120 (59.4%) patients were confirmed lymphoma relapse, 82 (40.6%) patients were histologically negative. Histologically negative results of 82 patients as follows: most (59.7%) patients were inflammation, 10 (2.1%) patients were solid tumor and 3 patients were tuberculosis. According to histologic subtype, PPV of Hodgkin's lymphoma was 25.0% (4/16), diffuse large B-cell lymphoma patients was 51.0% (47/92), mantle cell lymphoma (MCL) was 86.6% (13/15) and extranodal NK/T cell lymphoma (ENKL) was 85.7% (12/14) (Table 1). There was significant difference between PPV of aggressive B-cell non-Hodgkin lymphoma (NHL) except MCL and aggressive T-cell NHL (51.0% vs 78.5%, P=0.040). Indolent NHL was related with high PPV compared to aggressive B-cell NHL (70.2% vs 51.0%, P=0.032). Six (12.7%) patients of 47 indolent lymphoma were transformed to DLBCL at relapse. Four (8.5%) patients of 47 DLBCL patients showed histologic change to indolent lymphoma. There was no difference of predictive value according to stage, the number of extranodal involvement, lactic dehydrogenase and international prognostic index. PPV of FDG uptake in lymph node was 58.3% (63/108) and other sites except lymph node were 60.6% (57/94). Biopsy of stomach was 53.3% (8/15), small or large bowel was 55.5% (7/12). True positive patients of core biopsy was 61 (65.5%) of 93 patients, operation or excisional biopsy was 59 (67.0%) of 88 patients and aspiration cytology was 4 (19.0%) of 21 patients. Conclusion PPV of surveillance PET-CT in aggressive B-cell lymphoma was lower than indolent lymphoma or aggressive T-cell lymphoma. Surveillance PET-CT had clinical limitations according to histologic subtype of lymphoma. Histologic confirm by re-biospy should be recommended to exclude the false positive in aggressive B-cell lymphoma and distinguish the histologic transformation in indolent lymphoma. Table 1. Positive predictive value according to lymphoma subtype Pathology Lymphoma subtype positive negative Positive predictive value DLBCL (n=92) 47 45 51.0 MZBCL (n=26) 17 9 65.3 Follicular lymphoma (n=20) 16 4 80.0 Mantle cell lymphoma (n=15) 13 2 86.6 Burkitt lymphoma (n=3) 1 2 33.3 Plasmablastic lymphoma (n=1) 1 0 100 Lymphoplasmacytic lymphoma (n=1) 0 1 0 ENKL (n=14) 12 2 85.7 PTCL (n=11) 7 4 63.6 Mycosis fungoides (n=3) 2 1 66.6 Hodgkin's lymphoma (n=16) 4 12 25.0 Total (n=202) 120 82 59.4 Disclosures No relevant conflicts of interest to declare.

Long-term results confirmed that 18F-FDG-PET/CT was an excellent diagnostic modality for early detection of vascular grafts infection.

We sought to evaluate the potential role of positron emission tomography-computed tomography (PET-CT) for the detection and diagnosis of potential infections of vascular grafts using combining metabolic (i.e., radioactive fluorine-fluoro-D-deoxyglucose [18F-FDG]) PET with morphological (CT) information and investigate long-term capability. Seventeen patients with suspected vascular-graft infection underwent thoracic-abdominal-pelvic FDG PET combined with contrast-enhanced CT using a hybrid PET-CT scanner providing co-registered PET and CT images. In this retrospect study, we suspected graft infection in 14 of 17 patients detected using PET-CT and increased the maximal uptake of 18F-FDG around the grafts. Other vascular localizations were not observed. All patients with positive PET-CT results underwent redo-surgery, and the infection was ultimately confirmed using microbiological testing in 12 of 14 patients. Follow-up time was median of 58 months (range 36-73 months) for all 17 patients. In these patients, there was no further evidence of graft infection found on clinical and imaging follow-up. This is first investigation presenting long-term follow-up, which confirmed that 18F-FDG-PET/CT is an excellent diagnostic modality for suspected vascular graft infection. 18F-FDG PET-CT exhibited a sensitivity of 100% and specificity of 71.4% for the detection of vascular-graft infection.

Positron Emission Tomography-Computed Tomography: A Superior and One-Stop Shop Modality for Treated Head and Neck Carcinoma Compared With Conventional Tomography

The fusion imaging modality of positron-emission tomography-computed tomography (PET-CT) has emerged as an important modality in the management of recurrent head and neck tumors. The aims of this study were to assess the role of PET-CT in the detection of recurrence in treated head and neck squamous cell carcinoma (HNSCC) and compare neck PET-CT and contrast-enhanced computed tomography (CECT) in the detection of locoregional recurrence with histopathologic correlation. The study design was prospective and the study consisted of patients with treated HNSCC referred to the Department of Radiology at Rajiv Gandhi Cancer Institute and Research Center for follow-up or for clinical suspicion of recurrence. PET-CT and CECT neck images were obtained to detect recurrence based on clinical suspicion or as routine follow-up. Comparison of CECT and PET-CT results was performed using receiver operating characteristics (ROC) curves for the detection of locoregional recurrence with histopathologic correlation. Fifty-eight patients with treated HNSCC underwent neck PET-CT and CECT to detect recurrence based on clinical suspicion or as routine follow-up. The sensitivity and specificity of PET-CT for the detection of locoregional recurrence were 100% and 97.37%, which were considerably higher than 85% and 71.05% when using CECT. The ROC curve and its analysis showed that regional PET-CT is superior to neck CECT in the detection of locoregional recurrence (P = .02). When considering recurrence at the metastatic site, the sensitivity and specificity of PET-CT were 100% and 97.06%. PET-CT also detected second primary tumors in 2 patients. PET-CT not only is superior to conventional CECT in the detection of recurrence at locoregional and lymph node sites, but also plays a role in the restaging of recurrent tumors and the detection of distant metastases and second primary tumors. PET-CT, if included in routine post-treatment HNSCC follow-up or in a protocol for suspected recurrence, may have a major impact on the management of patients after treatment of HNSCC.

Laparoscopic Adrenalectomy for Solitary Adrenal Metastasis From Lung Cancer

Background and Objectives:Several studies have been reported on the problem of determining when laparoscopic adrenalectomy is indicated for solitary adrenal metastasis of malignant tumors. Our efforts at answering this question constitute the basis of this report.Methods:From June 2010 to June 2011, laparoscopic adrenalectomy was performed in 10 lung cancer patients with solitary adrenal metastases (5 adenocarcinomas, 1 squamous cell carcinoma, 1 large cell carcinoma, 1 small cell carcinoma, and 2 pleomorphic carcinomas). The surgical results of all 10 patients were examined.Results:Adrenal swelling was detected by computed tomography in all patients except 1 case of pleomorphic carcinoma. The findings of positron emission tomography–computed tomography were positive in 8 patients, including the 2 cases with pleomorphic carcinomas. Laparoscopic surgery was successfully performed in 9 cases. In the eighth patient (a case of pleomorphic carcinoma with adrenal swelling), laparoscopic adrenalectomy was attempted but conversion to open surgery was required because of clear evidence of pancreatic invasion.Conclusion:The results obtained in this study, along with other published reports, support 4 criteria as operative indications for laparoscopic adrenalectomy in solitary adrenal metastasis from the lung: (1) the primary lung cancer is resected or can be cured by radical chemotherapy, (2) metastasis is limited to the adrenal gland only, (3) adrenal metastasis does not invade the surrounding organs, and (4) the size of the adrenal tumor does not exceed 10 cm. In cases of pleomorphic carcinoma, laparoscopic adrenalectomy should be performed when positron emission tomography–computed tomography results are positive.

Is There Any Role of Positron Emission Tomography Computed Tomography for Predicting Resectability of Gallbladder Cancer?

The role of integrated (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography computed tomography (PET-CT) is uncertain in gallbladder cancer. The aim of this study was to show the role of PET-CT in gallbladder cancer patients. Fifty-three patients with gallbladder cancer underwent preoperative computed tomography (CT) and PET-CT scans. Their medical records were retrospectively reviewed. Twenty-six patients underwent resection. Based on the final outcomes, PET-CT was in good agreement (0.61 to 0.80) with resectability whereas CT was in acceptable agreement (0.41 to 0.60) with resectability. When the diagnostic accuracy of the predictions for resectability was calculated with the ROC curve, the accuracy of PET-CT was higher than that of CT in patients who underwent surgical resection (P=0.03), however, there was no difference with all patients (P=0.12). CT and PET-CT had a discrepancy in assessing curative resection in nine patients. These consisted of two false negative and four false positive CT results (11.3%) and three false negative PET-CT results (5.1%). PET-CT was in good agreement with the final outcomes compared to CT. As a complementary role of PEC-CT to CT, PET-CT tended to show better prediction about resectability than CT, especially due to unexpected distant metastasis.

The correlation of positron emission tomography-computed tomography assessment with histopathological results in the diagnosis of head and neck cancer of unknown primary

This study aims to evaluate the extent of the correlation between positron emission tomography-computed tomography (PET-CT) and histopathological and/or cytological evaluations in demonstrating malignancy and identifying the primary in patients with head and neck tumors of unknown primary. The excision records and files of 32 patients (24 males and 8 females; mean age 54.2 years; range 24 to 75 years) with previous PET-CT evaluations performed due to a mass with an unknown origin and to identify the primary were retrospectively analyzed. Positron emission tomography-computed tomography results and neck dissection (ND) materials were compared and PET-CT's ability to provide localization of the primer was determined by standardizing the study data. In respect of determining primary localization, PET-CT's sensitivity was determined as 66.6%, its specificity as 33.3%, its positive predictive value as 80%, and its negative predictive value as 20%. When the neck dissection specimens were considered according to the different regions they were obtained from: PET-CT's specificity was determined as 63.6%, its sensitivity as 94.5%, its positive predictive value as 87.5%, and its negative predictive value as 58.1%. Positron emission tomography-computed tomography sensitivity in determine the regions with pathologic lymph node involvement according to the BD specimen results and positive predictive value in identifying primary localization was found to be in accordance with the literature. Based on these results, PET-CT is a valuable method for early diagnosis and treatment in difficult cases.