Retroperitoneal Lymphadenopathy Research Articles

Primary retroperitoneal lymph node dissection in stage II testicular seminoma: a systematic review.

To conduct a systematic review of the current literature to determine the current role of primary retroperitoneal lymph node dissection (RPLND) in stage II testicular seminoma and its associated oncological, functional and peri-operative outcomes. A comprehensive literature search was conducted in Medline, Embase, and Scopus for publications from inception until November 2023. The systematic review was registered on PROSPERO (ID CRD42023449781), was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and utilised the Methodological Index for Non-Randomised Studies (MINORS) tool. Six studies involving 385 patients were analysed, with 48.5% clinical stage IIA and 51.5% stage IIB seminomas. The patients' mean (range) age was 37 (20-64) years. The median operation time was 187 min, median estimated blood loss was 150 mL and median length of hospital stay was 4 days. In all, 6.1% of patients developed complications that were greater or equal to Clavien-Dindo grade 3. Only four studies reported on anejaculation rate (median: 4.9%). Only one study had long-term data, demonstrating a 92% 5-year overall survival for stage IIA/B disease treated with RPLND. The remaining five studies had a median follow-up of between 18.5 and 37 months and reported a mean recurrence rate of 15.6%. Most recurrences (78%) were not within the field of RPLND. Recurrence was associated with higher clinical and pathological lymph node stage, and metachronous or delayed development of retroperitoneal lymphadenopathy (initially stage I disease, as opposed to de novo stage IIA/B disease). Primary RPLND, performed by experienced surgeons, has good peri-operative outcomes. Recurrence is more common than with standard treatment, but long-term survival and functional data are limited, although promising.

Impact of Retroperitoneal Lymphadenopathy (RPLN) on the Outcomes of Locally Advanced Gall Bladder Cancer (GBC) Following Chemotherapy (CT) or Chemotherapy Followed by Consolidation Chemoradiotherapy (CTRT).

Retroperitoneal lymphadenopathy is considered a metastatic disease in GBC; however, some surgical series of radical surgery with enlarged RPLN who underwent RPLN dissection have shown results marginally inferior to those without enlarged RPLN. Radiological RPLN comprises a major proportion of advanced non-metastatic GBC. There is dilemma in the intent of treatment to be offered in such cases. We are reporting our series of outcome of GBC with RPLN treated with first-line CT followed by consolidation CTRT. Non-metastatic locally advanced GBC with good performance status (KPS ≥ 80) were initiated on first-line CT (cisplatin-gemcitabine), and thereafter, responders were evaluated by CECT-angiography and PET-CT scan for resectability. If found unresectable, they were offered consolidation CTRT to a dose of 45Gy by conventional fractionation (3D-CRT technique) along with concurrent capecitabine at 1250mg/m2 to GBC and regional lymphatics including RPLN. Thereafter, boost dose of 9Gy/5# was given to GBC only. Response assessment was done using CECT abdomen by RECIST criteria v 1.1. Outcomes (overall survival) of the two groups (RPLN vs non-RPLN) were computed with Kaplan-Meier survival curves and chi-square tests using SPSS v 20. Among 189 patients of advanced non-metastatic GBC recruited from 2011 to 2022, 80 had RPLN. The demographic features of both groups were comparable. Overall, 68% of the patients were women, 30% underwent upfront stenting for obstructive jaundice, and 90% had T3 and T4 disease. Only 10% had undergone upfront laparoscopic staging and had pathologically proven RPLN. Forty percent of the patients received four cycles of CT only and 50% of the patients received six cycles or more and 33% received CTRT. By RECIST criteria, 10% vs 16% achieved complete response (CR), 39% vs 41% achieved partial response (PR), 16% vs 15% achieved stable disease (SD), 2.7% vs 6% had disease progression (PD), and 14.5% vs 3.7% were non-evaluable in non-RPLN group vs RPLN group, respectively. 12% vs 6% could undergo radical surgery in non-RPLN group vs RPLN group (p = 0.03). The median OS was 9months (95% CI 7.6-10.3months) vs 10months (95% CI 8-9.8months) (p = NS) in non-RPLN group vs RPLN group, respectively. In those who received CT only, the median OS was 7months vs 8months, while in those who received CT followed by CTRT, the median OS was 14months vs 13months (p = 0.65) in non-RPLN group vs RPLN group, respectively. Based on this analysis, we conclude that RPLN constitutes a major proportion of advanced non-metastatic GBC and has outcomes similar to those without RPLN if treated with radical intent. RPLN should not be considered a metastatic disease and should be treated with radical intent.

Hemophagocytic Lymphohistiocytosis as an Unusual Presentation in a Patient with Human Immunodeficiency Virus-associated Bone Marrow Classic Hodgkin Lymphoma: A Case Report with Literature Review

Abstract Introduction/Objective Compared to the general population, people living with human immunodeficiency virus (HIV) have a higher incidence of lymphoproliferative disorders including classic Hodgkin lymphoma (CHL). Hemophagocytic lymphohistiocytosis (HLH) triggers in HIV patients include HIV itself and HIV-associated malignancies or infections, all of which can have many overlapping symptoms, causing diagnostic challenges and delays in initiating treatments. Methods/Case Report A 56-year-old HIV-positive man presented with septic shock-like symptoms, pancytopenia, hyperferritinemia, transaminitis, elevated IL2-receptor alpha and hepatomegaly. Mild retroperitoneal lymphadenopathy found on imaging yielded non-diagnostic biopsies. A bone marrow (BM) biopsy showed no malignancy or disseminated infections and a rare hemophagocyte. Treatment for HIV-triggered HLH lead to a marked clinical improvement. Three months later he presented with worsening symptoms, negative cultures, and an EBV+ CHL on a BM biopsy. Mild increase in lymphadenopathy and multiple liver/spleen hypodensities found on imaging could not be biopsied due to rapidly deteriorating patient’s condition and death. Results (if a Case Study enter NA) NA Conclusion Per studies, HLH is more frequent in the HIV-associated lymphomas compared to the non-HIV- associated ones, usually presenting as a sepsis-like syndrome in these patients. Probability of HLH development was particularly high with BM involvement and CHL. From 2010, seven cases of HIV-associated CHL presenting with HLH were found in the literature with these findings: (n=8, including ours) sex- all males; average age- 45 years (range 28- 64); average HIV viral loads- 83,369 copies/mL (range: undetectable->300,000); average absolute CD4 count- 98 cells/microliter (range: 8-314); interval from HIV diagnosis- new to 26 years; anti-retroviral treatment- 6; symptoms- fever (all), other symptoms were variable; HLH-2004 protocol criteria- all; biopsy-proven hemophagocytes- 3; EBV+ CHL- all (6 were diagnosed on BM biopsies); outcomes- remission (2), response to treatment (4), death (2). CHL- triggered HLH in HIV patients is a complex diagnostic entity. A high index of suspicion and thorough investigations including early BM biopsies can ensure better outcomes.

Primary mucinous adenocarcinoma intestinal type of the vulva arising at site of prior vulvar Crohn’s disease: A case report and review of the literature

Introduction: Vulvar mucinous adenocarcinoma is a rare subtype that likely arises from atopic gastrointestinal tissue. The evaluation and treatment of this condition often requires a multidisciplinary approach. Case Report: Our patient is a 55-year-old female with a history of Crohn’s disease who initially presented with a painless vulvar mass associated with occasional bleeding. Notably, the mass presented at the site of a prior rectovaginal fistula. A vulvar biopsy was performed with pathology consistent with intestinal type mucinous adenocarcinoma. Further workup was notable for imaging showing retroperitoneal and pelvic metastatic lymphadenopathy, hypermetabolic liver and bony metastases, and pulmonary nodules concerning for metastases. Following discussion at tumor board, the patient was recommended treatment with 5-fluorouracil, leucovorin, oxaliplatin (FOLFOX), and bevacizumab. Unfortunately, prior to starting chemotherapy, the patient presented to the emergency department with dizziness and weakness and was found to have brain metastases. She ultimately elected to be discharged home on hospice care. Conclusion: Vulvar mucinous adenocarcinoma is a rare subtype tumor with limited literature on treatment options. For these rare cases, clinicians can consider treatment modalities for colon carcinomas rather than vulvar carcinomas.

Metastatic onset of prostate carcinoma: A clinical and pathological challenge.

Prostate cancer is the second most common cancer, following lung cancer, and the fifth leading cause of cancer death in men worldwide. The onset of the disease, characterized by symptoms or changes caused by distant metastases, is rare and poses a challenge for clinicians and pathologists. We aimed to present a series of prostate carcinoma (PC) with unusual, histologically confirmed distant metastases (pM1) at the time of diagnosis, which raised suspicions of other types or origins of the primary tumor. Patients diagnosed with PC and distant metastases within a five-year timeframe (2017-2022) were extracted from the hospital database. The following data were collected: patient's age, imaging data, serum PSA level, and histopathological evaluation results. Patients with unusual distant metastases were selected and analyzed. We identified 10 patients in whom the diagnosis of PC was established following histopathological examination of tissue taken from distant metastatic sites (pM1). In three patients, the location of distant metastases was unusual: retroperitoneal, cranial/dural/epicranial and supradiaphragmatic lymph nodes which posed diagnostic challenges. Establishing the prostate origin of the tumor relied on immunohistochemical (IHC) investigation guided by clinical-imaging information. A metastasis of PC may rarely present as a cranial/dural tumor, retroperitoneal, or supradiaphragmatic lymphadenopathies in a man over the age of 50, but it should be taken into consideration. In the absence of correlated clinical, imaging, and histopathological/IHC data, diagnosing distant metastasis from PC is difficult, especially considering its potentially confusing IHC profile.

An Uncommon Cause of Elevated Liver Transaminases: Immune Reconstitution Inflammatory Syndrome from Unmasking of Occult Mycobacterium Avium Complex Infection in an HIV Infected Patient

Abnormal liver chemistry from the development of immune reconstitution inflammatory syndrome (IRIS) may reflect an unmasking of subclinical disease. We present the case of a 37-year-old female with a mixed pattern of liver injury from disseminated mycobacterium avium complex infection after starting antiretroviral therapy (ART). Presenting symptoms were fever, confusion, dysphagia, and abdominal discomfort for one week. Exam revealed a fever of 103.2°F, hypotension, encephalopathy, and abdominal tenderness. Lab work was significant for acute normocytic anemia, leukopenia, absolute CD4 count 28 cells/cmm, HIV viral load 276 viral copies/ml (vc/ml), ALT 267 U/L, AST 484 U/L, alkaline phosphatase 342 U/L, and normal total bilirubin. Imaging revealed hepatomegaly with steatosis and mesenteric and retroperitoneal lymphadenopathy. Percutaneous liver biopsy demonstrated noncaseating granulomas with AFB-positive organisms, with AFB blood cultures growing Mycobacterium avium complex (MAC), consistent with disseminated MAC infection. Clinicians must have a high index of suspicion for IRIS when determining the etiology of elevated liver transaminases in patients with HIV.

Cannonball Pulmonary Metastases as Initial Presentation of Hepatocellular Carcinoma: A Case Report and Literature Review

BackgroundHepatocellular carcinoma is a major public health problem, as is considered the fastest growing cause of cancer-related death. Cannonball metastases as an initial finding in hepatocellular carcinoma are considered a rare phenomenon.Case PresentationA 59-year-old man presented to the outpatient clinic for subacute cough, asthenia, and involuntary weight loss. Chest X-ray showed multiple, round, bilateral pulmonary solid lesions. Contrast-enhanced computed tomography of the chest and abdomen revealed multiple bilateral, contrast-enhanced pulmonary nodules known as "cannonball" lesions and a heterogeneous lesion located in the right lobe of the liver with retroperitoneal lymphadenopathy. A biopsy was performed, and the histopathological result was compatible with metastatic poorly differentiated hepatocellular carcinoma. Due to the advanced stage of the disease, the patient received palliative care and expired two months later.ConclusionCannonball metastases in hepatocellular carcinoma are considered a rare finding and represents a poor prognosis. It is important to awaken the interest of clinicians in a timely diagnosis, as well as a possible suspicion of hepatocellular carcinoma in patients with this radiographic pattern.

A malignancy phantom: a rare clinical case report of metastatic renal cell carcinoma with no evidence of a primary lesion presenting as cerebellar ataxia

Background: Anti-Ma2 antibody associated paraneoplastic syndrome (PNS) usually presents as limbic encephalitis in the context of testicular tumors. We report a rare case of anti-Ma2 positive PNS with deviation from the classic scenario, thus expanding the phenotype of anti-ma2 associated PNS. Case presentation: This is a 53-year-old male who presented with what was later diagnosed as anti-Ma2 antibody positive cerebellar ataxia. Further workup revealed retroperitoneal lymphadenopathy which, using biopsy, was identified as metastatic clear cell renal cell carcinoma (RCC). However, imaging did not reveal a primary renal lesion. Conclusion: Physicians should be aware of non-classic presentations of paraneoplastic syndromes, especially given that they commonly precede and point towards an underlying, many times undiagnosed, malignancy.

Survival in esophageal cancer with nonregional lymphadenopathy: a propensity score–matched analysis

BackgroundSurvival among esophageal cancer patients with stage IV non-regional lymphadenopathy treated with neoadjuvant therapy and surgical resection is not well described. This study aimed to compare the survival outcomes of patients with non-regional lymphadenopathy with a propensity matched cohort of patients with loco-regional disease. MethodsA retrospective cohort analysis of a prospectively maintained database from a regional upper gastrointestinal cancer network in Quebec, Canada was performed. From 01/2010 until 12/2022, patients with radiologically suspicious non-regional retroperitoneal or supraclavicular lymphadenopathy were identified. Using 1:1 propensity score matching, a control group without non-regional disease was created. ResultsOf the 1235 patients identified, 39 met the inclusion criteria and were allocated to the study group of whom 35/39 (89%) had adenocarcinoma. Retroperitoneal and supraclavicular lymphadenopathy occurred in 26/39 (67%) and 13/39 (33%). Thirty-four received neoadjuvant chemotherapy (87%) and 5/39 (13%) chemoradiotherapy. Following resection, ypN0 of non-regional lymph node stations occurred in 21/39 (54%). When comparing the study group with a matched non-Stage IV control group, median overall survival was similar in patients with retroperitoneal lymphadenopathy (21 months, 95% CI 8-21 vs 27.0, 95% CI 13-41 p=0.262) but not with supraclavicular disease (13 months, 95% CI 8-18,p=0.039). Median follow up was 40.1 months (95% CI 1-83) and 70.0 (95% CI 33-106) for the study and control groups. ConclusionsCompared to a matched cohort of patients with similar disease burden but not stage IV disease, retroperitoneal lymphadenopathy did not negatively affect survival outcomes. Multimodal curative intent therapy may be appropriate in select cases.

Retroperitoneal lymphadenopathy: An underappreciated contributor to acute kidney failure in patients with cancer

Introduction: Retroperitoneal lymphadenopathy represents a unique and infrequent complication within various malignancies. This case report exemplifies the intricate diagnostic challenges that arise when identifying nondilated obstructive nephropathy in the context of retroperitoneal lymphadenopathy due to diffuse large B-cell lymphoma (DLBCL), particularly when conventional imaging fails to reveal the hallmark feature of hydronephrosis. Case description: We present a 66-year-old male with relapsed chronic lymphocytic leukemia post-allogeneic stem cell transplantation. His direct admission to the hematology/oncology service was due to failure to thrive. Despite the absence of hydronephrosis on imaging, the patient developed volume overload and increased serum creatinine levels. An ultrasound unveiled mild bilateral collecting system dilation, while laboratory findings did not provide valuable insight into the underlying etiology. A Lasix renal scan confirmed split renal function with minimal bilateral excretion. High clinical suspicion resulted in an MRI scan showing interval enlargement of retroperitoneal lymph nodes and pelvicaliectasis, which prompted urological and interventional radiology involvement. Conclusions: This case underscores the complexity of diagnosing retroperitoneal lymphadenopathy and pelvicaliectasis, in DLBCL, particularly when hydronephrosis is absent on imaging. It emphasizes the significance of clinical acumen, collaboration among specialties, and the use of advanced imaging techniques. Timely recognition of nondilated obstructive nephropathy in the setting of retroperitoneal lymphadenopathy is pivotal for guiding appropriate management strategies and optimizing patient outcomes in the intricate clinical setting.

SMARCB1-Deficient Skull Base Chondrosarcoma with 12p Duplication Presenting as Somatic-Type Malignancy Arising from Metastatic Seminoma

Somatic-type malignancy (STM) can occur infrequently within a primary or metastatic testicular germ cell tumor (TGCT) and is associated with dismal prognosis and survival. STM with chondrosarcomatous features is exceedingly rare and head and neck involvement has not been previously documented. A 39-year-old white man presented with nasal obstruction and epistaxis. Imaging disclosed a 6.9-cm expansile tumor involving the nasal cavity and skull base with intraorbital and intracranial extension. The histopathologic properties of the tumor were compatible with chondrosarcoma, grade II-III. Immunohistochemically, malignant cells were strongly and diffusely positive for S100 and epithelial markers, and showed loss of SMARCB1 expression. IDH1/2 mutations were not detected. Following whole-body PET scan, a 7.0-cm left testicular mass was discovered and diagnosed as seminoma with syncytiotrophoblastic cells, stage pT3NXM1b. Extensive retroperitoneal, mediastinal, and supraclavicular lymphadenopathy was also noticed. Histopathologic examination of the left supraclavicular lymph node revealed metastatic seminoma. By FISH, most metastatic nodal seminoma cells harbored 1 to 4 copies of isochromosome 12p, while the chondrosarcoma featured duplication of 12p. Presence of a malignant TGCT with disseminated supradiaphragmatic lymphadenopathy, the unique immunophenotypic properties of the skull-based chondrosarcoma and lack of IDH1/2 aberrations with gain of 12p strongly support the diagnosis of STM chondrosarcoma arising from metastatic TGCT. The patient did not respond to chemotherapy and succumbed three months after diagnosis. Although exceedingly uncommon, metastasis to the head and neck may occur in patients with TGCT. This case of STM chondrosarcoma demonstrated divergent immunophenotypic and molecular characteristics compared to “typical” examples of head and neck chondrosarcoma. High index of suspicion is advised regarding the diagnosis of lesions that present with otherwise typical histomorphology but unexpected immunohistochemical or molecular features.

A malignancy phantom: a rare clinical case report of metastatic renal cell carcinoma with no evidence of a primary lesion presenting as cerebellar ataxia

Background: Anti-Ma2 antibody-associated paraneoplastic syndrome (PNS) usually presents as limbic encephalitis in the context of testicular tumors. We report a rare case of anti-Ma2 positive PNS with deviation from the classic scenario, thus expanding the phenotype of anti-ma2 associated PNS. Case Presentation: This is a 53-year-old male who presented with dizziness and visual changes and was later diagnosed with anti-Ma2 antibody-positive cerebellar ataxia. Further workup revealed retroperitoneal lymphadenopathy which, using biopsy, was identified as metastatic clear cell renal cell carcinoma. However, imaging did not reveal a primary renal lesion. Conclusion: Physicians should be aware of non-classic presentations of PNSs, especially given that they commonly precede and point towards an underlying, many times undiagnosed, malignancy.

Mesenteric Lymphadenopathy: a Rare Case of Rosai-Dorfman Disease

Introduction: 
 Rosai-Dorfman Disease (RDD) is rare with approximately 100 new cases annually in the United States and a mean age of 20.6 years [1]. RDD is characterized by massive lymphadenopathy and sinus histiocytosis [1]. Bilateral cervical lymphadenopathy is the typical presentation, however extra nodal sites have been noted [1]. This case discusses manifestations of a rare disease state. 
 Case Presentation: 
 A 19 year old male with a history of eczema and juvenile rheumatoid arthritis presented to the emergency room with four days of diffuse abdominal pain localized to the left upper quadrant, radiation to the right lateral ribs with nausea and diarrhea. He reported an unintentional weight loss of 30 pounds in the last three months. Physical exam revealed generalized abdominal tenderness and rebound. Computed tomography of the abdomen and pelvis (CTAP) along with routine labs were ordered. CTAP showed retroperitoneal lymphadenopathy up to two centimeters in the short axis (figure 1) and mesenteric adenopathy with a 15 millimeter lymph node in the right lower quadrant. Histopathology reported necrotizing granulomatous lymphadenitis with benign sinus histiocytes. Referral to rheumatology was made and treatment was initiated with prednisone 20 milligrams daily with plans for repeat abdominal imaging to evaluate for reduction of adenopathy. 
 Discussion: 
 RDD coexists with immunologic disease in 10% of cases.3 It has been associated with systemic lupus erythematous, idiopathic juvenile arthritis, autoimmune hemolytic anemia,24 and one case of RAS-associated autoimmune leukoproliferative disease [1]. The prognosis for RDD is indolent, 50% of patients experiencing resolution, one third with residual asymptomatic adenopathy and 17% with persistent symptomatology [2]. Our case highlights our patient’s associated history of juvenile rheumatoid arthritis now presenting with histological findings of RDD. A methodical approach to assessing patients with diffuse abdominal pain and ensured collaboration amongst different medical specialists will ensure favorable treatment outcomes.

Metastatic micropapillary cervical adenocarcinoma presenting as a cystic neck mass: a diagnostic pitfall that can be mistaken with metastatic papillary thyroid carcinoma

Abstract Introduction/Objective Micropapillary endocervical adenocarcinoma is a rare aggressive variant of cervical adenocarcinoma with a high propensity for lymphovascular spread and poor outcomes. A 69-year-old woman presented with bilateral neck masses for 6 months. Imaging showed multiple multilocular cystic lateral neck masses. Fine needle aspiration was non-diagnostic. A core biopsy showed a papillary adenocarcinoma positive for TTF-1, Napsin-A, and PAX-8 immunostains, and negative for thyroglobulin, interpreted as metastatic papillary carcinoma of possible lung or thyroid origin. Further imaging of the head, neck, and thorax did not reveal a clear primary, but there was extensive involvement of the neck and mediastinal lymph nodes. Given the disease distribution and prominent cystic change in the nodal metastases, the patient underwent total thyroidectomy, bilateral neck, and mediastinal dissections for a presumed thyroid primary. No tumor was found in the thyroid gland. On follow-up the patient was noted to have normal serum thyroglobulin and retroperitoneal lymphadenopathy on PET/CT scan, prompting the search for a pelvic source. Additional immunostains performed in existing samples showed strong estrogen and progesterone receptor expression suggesting a gynecologic primary. At reevaluation, it was found that the patient had postmenopausal bleeding for a year. The colposcopy examination was normal, but a pap smear showed adenocarcinoma. An endocervical biopsy confirmed a micropapillary variant of endocervical adenocarcinoma. Methods/Case Report case report Results (if a Case Study enter NA) NA Conclusion Micropapillary carcinomas occur at multiple sites and are associated with the prominent lymphovascular spread and poor outcomes. The association of prominent neck and mediastinal lymphadenopathy, papillary architecture, cystic metastases, and coexpression of TTF-1, Napsin-A, and PAX-8 led to an erroneous presumption of a thyroid primary. This case highlights how overlapping immunomorphological features between thyroid and gynecologic tumors with papillary architecture, anchoring and confirmation biases, and suboptimal anamnesis can lead to an erroneous diagnosis.

SAT213 Post-parathyroidectomy Acute Pseudogout Flare-up; A Case Report

Abstract Disclosure: S. Rabiei: None. V. Kantorovich: None. Introduction: Acute post-parathyroidectomy pseudogout has been reported in the early post-operative. Although the exact mechanism is unknown, accepted theories include decreased solubility of calcium pyrophosphate and unbalanced equilibrium between production and hydrolysis of inorganic phosphate. We present a patient who developed an acute pseudogout attack after parathyroidectomy. The Case: Patient is a 45-year-old male with a history of nephrolithiasis who presented to outpatient clinic with a right-sided neck mass that has been present for several years with recent increase in size. He reported unintentional weight loss (25 pounds) and night sweats. On physical examination, a right lateral neck mass measuring 6 x 4 cm was noted. CT scan of the neck demonstrated a complex mass with calcification. Serum calcium (Ca), phosphorus (P), potassium (K), and alkaline phosphatase levels were 17.2 mg/dL, 1.8 mg/dL, 2.6 mmol/L, and 1,782 U/L, respectively. Serum intact parathyroid hormone (iPTH) was 3,341 pg/mL. The patient was then admitted. He received intravenous fluid, zolindronic acid, and started on vitamin D supplementation in preparation for surgery. Pre-operative CT scan of the chest, abdomen, and pelvis was concerning for metastatic disease (retroperitoneal lymphadenopathy, multiple bilateral lung solid nodules, liver, kidney and bone lesions). The patient underwent complete resection of the tumor. Intra-operative frozen section confirmed parathyroid tumor with atypia. Twenty-minute post-excision iPTH was 476 pg/mL. In the early post-operative period, serum Ca level was reduced to 7.5-8.5 mg/dL and oral Ca and calcitriol supplementation were administered. However, serum PTH reached levels as high as 900 pg/mL. Post-operative MRI demonstrated benign liver and kidney lesion with non-visualization of the previously reported retroperitoneal lymph nodes and pulmonary nodules on the CT.A few days later, the patient complained of bilateral knee pain. Serum Ca, P, and PTH levels were 7.9 mg/dL, 3.0 mg/dL, and 861 pg/mL, respectively. The skeletal survey revealed diffuse osseous metabolic process with scattered lucent osseous lesions compatible with osteitis fibrosa cystica/brown tumors as well as chondrocalcinosis of knees and hand joints. Prednisone was started for treatment of presumed acute CPPD attack with subsequent significant resolution of patient’s joint pain. Discussion: This case demonstrated the importance of thorough evaluation of musculoskeletal complaints in patients with hyperparathyroidism. Bone and joint pain in patients with hyperparathyroidism is common and is most often the result of high bone turnover. However, other etiologies including acute pseudogout should be contemplated in order to provide the appropriate treatment. Post-parathyroidectomy acute pseudogout attack should generally be treated in the same way as in the general population. Presentation: Saturday, June 17, 2023

FRI228 Primary Adrenal T-cell Lymphoma: A Case Report

Abstract Disclosure: H. Tabassum: None. S. Xu: None. A. Manavalan: None. Introduction: Primary T-cell adrenal lymphoma (PAL) is exceedingly rare. Adrenal insufficiency (AI) is common in these cases. Here we describe a patient with bilateral, large, T-cell PAL with rapid progression, without adrenal insufficiency. Clinical Case: A 62-year-old male, with coronary artery disease and recent coronary intervention, hyperlipidemia and hypertension presented to the hospital with abdominal pain, fever, night sweats and weight loss for a month. Work up revealed a 5.8 cm left adrenal mass with 14% absolute washout, measuring 34 Hounsfield Units (HU) pre-contrast, 68 HU postcontrast, and 63 HU on delayed images, and a 5.2 cm right adrenal mass with 42% absolute washout, measuring 35 HU pre-contrast, 81 HU postcontrast, and 62 HU on the delayed images with no other suspicious lesions or lymphadenopathy. The patient demonstrated no clinical symptoms or signs of adrenal hormone excess or deficiency. Levels of renin, aldosterone, serum cortisol, ACTH, 24-hour urine free cortisol, serum metanephrines, and thyroid function were normal. Additional tests to rule out adrenal cortical carcinoma (ACC) revealed normal levels of androstenedione, 17-hydroxyprogesterone, dehydroepiandrosterone sulfate, and estradiol. Persistent non-significant elevation of 11-deoxycortisol was observed at 51 ng/dL and 63ng/dL (Ref < 42 ng/dL). Adrenal biopsy was suggested but deferred due to the increased risk of hemorrhage given recent coronary revascularization and use of dual antiplatelet therapy. Follow up imaging in a few weeks revealed diffuse, retroperitoneal lymphadenopathy with unchanged adrenal masses. A lymph node biopsy confirmed a diagnosis of peripheral T-cell lymphoma. The left adrenal gland demonstrated an uptake SUV of 22.7 and the right, 19.17 on FDG PET. The patient was initiated on chemotherapy with etoposide, prednisone, vincristine sulfate, cyclophosphamide, and doxorubicin. Imaging three months later revealed a marked decrease in FDG activity SUV 6.98 g/mL on the left and SUV up to 3.32 g/mL on the right. Adrenal function remained intact on follow up. Conclusion: Peripheral T-cell lymphoma with adrenal involvement is an extremely rare and aggressive disease with rapid progression. Mostly seen in males over the age of 50, it may present with abdominal pain, B symptoms or both. While ACC is usually unilateral, lymphoma and metastatic disease may present bilaterally, however, other imaging features can be similar. AI is expected when 90% of the adrenal glands are destroyed by tumor infiltration, however, this does not always correlate with tumor size. In our patient, AI was not observed on presentation or follow up. As adrenal insufficiency can occur at any time in the disease course and may mimic symptoms of cancer or chemotherapy, the clinician should always be vigilant for its development in these cases. Presentation: Friday, June 16, 2023

FRI498 Paraneoplastic Hyperthyroidism In A Patient With B-hCG Secreting Gastric Carcinoma

Abstract Disclosure: F. Perreault: None. M. Tehfe: None. M. Laskine: None. L. Ste-Marie: None. R. Comtois: None. B. Nguyen: None. J. Murphy-Lavallée: None. A. Rakel: None. Introduction: Human chorionic gonadotropin (hCG) has thyrotropic activity, due to a similar structure to TSH. Increased hCG serum levels can cause hyperthyroidism secondary to TSH-receptor activation. hCG can be increased in conditions outside of pregnancy, such as gestational trophoblastic disease and other tumors. Common hCG secreting tumors are non-seminomatous germ cell tumors, including choriocarcinoma and teratoma1. Even if gastric adenocarcinomas can secrete ß-hCG, the serum level is rarely elevated2. Clinical Case: A 75-year-old man presented to the hospital for abdominal pain, diarrhea, and important recent weight loss. The patient was known for hypertension, dyslipidemia, type 2 diabetes, and chronic kidney disease. He had been investigated for sub-clinical hyperthyroidism one year prior (TSH 0.27 mUI/L (N 0.38-5.33), T4 14 pmol/L (N 8.0-20.0), T3 4.7 pmol/L (N 3.8-6.0), normal thyroid ultrasound and normal uptake at scintigraphy). At physical examination, the patient looked anxious, had a light lid lag, sinus tachycardia (120 BPM) and a new systolic heart murmur. The thyroid exam was normal and there was no pretibial myxedema nor exophthalmia. The blood tests showed normocytic anemia (Hb 113 g/L, N>130), low TSH (< 0.01 mUI/L), and elevated free T4 (74.1 pmol/L) and T3 (22.5 pmol/L). A work-up for hyperthyroidism revealed normal anti-TPO (4 UI/mL, N<9) and TSH receptor (1.2 UI/L, N<1.8) antibodies levels. Tc-99m thyroid scintigraphy showed homogeneous and intense uptake, with no nodule. Additionally, the abdominal CT-scan revealed multiple retroperitoneal lymphadenopathies and liver hypodensities, suspicious of neoplasia. In this context, the patient underwent gastroscopy, and a gastric antral mass was discovered. Neoplastic markers were measured and, unexpectedly, ß-hCG was strongly elevated (>1 080 800 U/L, N<2.0). Testicle ultrasound was normal. The antral mass biopsy was consistent with infiltrating gastric adenocarcinoma, with ring cells containing intracellular mucin and expressing hCG. The patient was treated with methimazole and propranolol. Free T3 and T4 initially decreased with this treatment (to 7.1 pmol/L and 46.4 pmol/L respectively), but one month later, the serum values were higher (14.9 pmol/L and 69.2 pmol/L). No follow-up was possible for this patient as he passed away before receiving treatment for cancer. Conclusion: ß-hCG induced hyperthyroidism can aggravate patients’ malignant manifestations and should be considered in cases presenting with concomitant cancer and hyperthyroidism.

Primary pancreatic Ewing sarcoma with metastases on FDG PET/CT

BackgroundEwing sarcoma (ES) is a highly aggressive malignant tumor most commonly affecting long bones. Extraskeletal Ewing sarcoma (EES) is a malignant tumor with aggressive behavior carrying bad prognosis with pancreas being an extremely rare primary site. We present a case of histopathologically proven EES of the pancreas in a young female who presented with abdominal pain. 18F-fluorodeoxyglucose positron emission tomography (18F FDG PET/CT) is a useful modality for detecting distant metastases in EES. It helps in diagnosis, localizing the primary, its extension, optimal treatment planning and evaluation of response to standard treatments available.Case presentationAn 18-year-old female presented with complaints of progressive abdominal pain and distention since 6 weeks. Physical examination was suggestive of a solid large mass in the upper left abdomen and decreased breath sounds with dullness in the left lower lung fields. On Contrast enhanced computed tomography (CECT) imaging, a large heterogeneously enhancing mass was seen arising from pancreas along with retroperitoneal lymphadenopathy. A moderate sized left sided pleural effusion with atelectasis of lower lobe of left lung was also noted. Histopathological analysis was suggestive of pancreatic ES following which the patient underwent five cycles of chemotherapy. Following this, she underwent 18F FDG PET/CT which showed hypermetabolic large mass arising from body and tail of pancreas with areas of internal necrosis along with left adrenal metastasis, retroperitoneal lymphadenopathy, a massive left pleural effusion and compressive atelectasis of left lower lobe. The patient expired within a week following PET/CT.ConclusionsEES most often presents in the late stage of the disease with vague symptoms. Timely diagnosis and initiation of treatment is of utmost importance considering the aggressiveness of the tumor. Establishing a diagnosis of Ewing sarcoma is especially difficult when the mass is arising from the pancreas. Imaging, histopathology and immunohistochemistry (IHC) play a key role in accurate diagnosis of such masses. 18F FDG PET/CT can be useful for detecting local and distant spread, operability, treatment planning and evaluation of response to chemotherapy.

176. NON-REGIONAL LYMPHADENOPATHY IN PATIENTS WITH ESOPHAGEAL CANCER TREATED WITH CURATIVE INTENT: A PROPENSITY MATCHED ANALYSIS OF PATHOLOGICAL AND SURVIVAL OUTCOMES

Abstract Background The management of patients with esophageal cancer and concurrent retroperitoneal or supraclavicular lymphadenopathy is controversial. Whilst these patients could be considered non-resectable, the survival benefit of neoadjuvant treatment followed by en bloc resection is not well described. The aim of this study was to explore the perioperative, pathological and survival outcomes of patients with esophageal cancer who presented with oligometastatic non-regional lymphadenopathy treated with neoadjuvant therapy and subsequent en bloc transthoracic esophagogastrectomy. Methods Between 01/2010 and 12/2022, a single center retrospective review of a prospectively maintained comprehensive esophageal cancer surgical database was performed. All patients with esophageal and junctional cancer with clinical non-regional (supraclavicular and retroperitoneal) lymphadenopathy were identified (Tany, Nany, M+). Only patients treated with neoadjuvant chemotherapy/chemoradiotherapy (nCT/nCRT) and extended en bloc transthoracic esophagogastrectomy including resection of the non-regional lymph node basin were included. Patients with gastric cancer and solid organ metastases were excluded. Propensity score matching was used to create a control group of clinically M- patients from same database to compare survival outcomes. Results Of the 46/1235 patients with non-regional lymphadenopathy, 39 met the inclusion criteria. Most had adenocarcinoma (35/39,89.7%) with retroperitoneal and supraclavicular lymphadenopathy in 26/39 (66.7%) and 16/39 (41.0%). nCRT and nCT was used in 5 and 34 patients respectively. Twenty-four received taxane based regimens and 24/39 (61.5%) adjuvant therapy. A trend towards improved overall survival was noted when comparing the study and control groups (27.0 vs 17.0 months, p = 0.065). However, cM+(retroperitoneal) had similar survival to the control group with both being higher than cM+(supraclavicular) (27.0 vs 21.0 vs 13.0 months, p = 0.039). Non-regional nodal basin sterilization occurred in 20/36 (55.6%) and was not associated with improved survival. Conclusion Whilst non-regional lymph node disease in the setting of esophageal cancer can be treated with neoadjuvant therapy and curative en bloc extended transthoracic resection, it seems that in terms of survival patients with retroperitoneal disease benefit the most. In this group of patients, equivalent survival to those with non-metastatic disease is achievable. Further understanding into those who would benefit from such a regimen is urgently needed.

Patterns of Relapse in Australian Patients With Clinical Stage 1 Testicular Cancer: Utility of the Australian and New Zealand Urogenital and Prostate Cancer Trials Group Surveillance Recommendations.

International guidelines advocate for active surveillance as the preferred treatment strategy for patients with stage 1 testicular cancer after orchidectomy although a personalized discussion is required. We conducted an analysis of individuals registered in iTestis, Australia's testicular cancer registry, to describe the patterns of relapse and outcomes of patients treated in Australia where the Australian and New Zealand Urogenital and Prostate Cancer Trials Group Surveillance Recommendations are widely adopted. A total of 650 individuals diagnosed between 2000 and 2020 were included, 63% (411 of 650) seminoma and 37% (239 of 650) nonseminoma. The median age was 34 years (range 14-74). 26% (106 of 411) with seminoma and 15% (36 of 239) nonseminoma received adjuvant chemotherapy. After a median follow-up of 43 months (range 0-267) postorchidectomy, relapse occurred in 10% (43 of 411) of seminoma and 18% (43 of 239) of nonseminoma. The two-year relapse-free survival was 92% (95% CI, 89 to 95) and 82% (95% CI, 78 to 87) in seminoma and nonseminoma, respectively. All relapses (86 of 86) were detected at a routine surveillance visit; 98% (85 of 86) were asymptomatic and detected solely through imaging (62 of 86, 72%), tumor markers (6 of 86, 7%), or a combination (17 of 86, 20%). The most common relapse site was isolated retroperitoneal lymphadenopathy (53 of 86, 62%). No nonpulmonary visceral metastases occurred. At relapse, 98% (84 of 86) had International Germ Cell Cancer Collaborative Group (IGCCCG) good prognosis; 2 of 86 intermediate prognosis (both nonseminoma). No deaths occurred. In our cohort of stage 1 testicular cancer, where national surveillance recommendations have been widely adopted, recurrences were detected at routine surveillance visits and, almost exclusively, asymptomatic with IGCCCG good-prognosis disease. This provides reassurance that active surveillance is safe.