Soft Tissue Mass Research Articles

A Case Report on Ellis–van Creveld Syndrome: Clinical, Embryological, Anesthetic, and Surgical Implications

AbstractPostaxial polydactyly (PAP) in the form of rudimentary soft tissue masses is quite common. Management involves ligation or surgical excision. Rarely do literature discussions cover complex variants in which the extra finger is fully developed. Ellis–van Creveld syndrome (EVC) or chondroectodermal dysplasia is a rare disorder characterized by PAP. When chondral dysplasia encompasses PAP, dwarfism, and genu valgum, ectodermal dysplasia involves nails and teeth. We describe two EVC cases. When one had cardiac malformations, the other had dental anomalies. One of them underwent genu valgum correction and removal of the additional finger. The hand surgery proved complex due to fusion of its metacarpal with the fifth metacarpal. Pediatric Outcomes Data Collection Instrument (PODCI) scores at 1.5 and 2.5 years after hand and knee surgeries were excellent. A multidisciplinary approach is essential to achieve comprehensive care. Additional embryological research is necessary to elucidate the clinical manifestations described in this report.

Mesocolic schwannoma mimicking gastrointestinal stromal tumor: A case report and review of literature.

Schwannomas are common peripheral nerve tumors originating from Schwann cells, primarily occurring in the head and neck, limbs, and trunk. Schwannomas occurring in the mesocolon are rare and often have no specific manifestations. Abdominal schwannomas need to be differentiated from common abdominal tumors such as gastrointestinal stromal tumors. We report a case of a mesocolic schwannoma in a 59-year-old female presenting with gastrointestinal symptoms of acid reflux. At an outside hospital, gastroscopy, colonoscopy, and abdominal computed tomography scans revealed a soft tissue mass adjacent to the greater curvature of the stomach, leading to a suspicion of a gastric mesenchymal tumor. Mesocolic schwannoma. Laparoscopy was performed at our hospital. Intraoperatively, the tumor was found to be closely related to the transverse colon and was initially diagnosed as a mass originating from the transverse colon. Consequently, a resection of the mass along with the adherent portion of the transverse colon was performed. Postoperative pathology and immunohistochemistry confirmed that the tumor was a schwannoma of the mesentery and did not originate from the transverse colon. Schwannomas can be distinguished from gastrointestinal stromal tumors by immunohistochemical staining, and surgical treatment is effective for benign schwannomas.

Rare posterior mediastinal hemangiomas invading the spinal cord through the intervertebral foramen and causing acute symptoms: illustrative case.

Hemangioma is a rare vascular tumor characterized by endothelial cell proliferation that primarily occurs in soft tissues. While most cases in the paraspinal posterior mediastinum are clinically indolent, they can also exhibit aggressive growth, leading to severe clinical outcomes and necessitating urgent treatment. A 61-year-old right-handed female presented with reduced lower-extremity mobility that had begun 4 days earlier. An examination revealed that both lower limbs had grade 4 muscle strength. Computed tomography and magnetic resonance imaging revealed a right T1-3 paravertebral dumbbell-shaped soft tissue mass invading the spinal canal, destroying the T2 vertebra, and compressing the spinal cord and nerve roots. Elective surgery was planned, but a rapid muscle strength decline prompted emergency surgery. Postoperative muscle strength improved to grade 4, and at the 3-month follow-up, muscle strength had fully recovered. Postoperative pathological examination revealed that the mediastinal dumbbell-shaped lesion was a hemangioma. While most hemangiomas progress slowly, acute symptoms of spinal cord compression are exceedingly rare. This case demonstrates the aggressive behavior of hemangioma, which invaded through the intervertebral foramen and compressed the spinal cord, resulting in acute symptoms. This case also shows that surgical removal of the tumor and restoration of spine stability via a posterior approach has proven beneficial. https://thejns.org/doi/10.3171/CASE24485.

Epidermal Inclusion Cyst Presenting as Prepatellar Bursitis

An epidermal inclusion cyst is one of the rare benign lesions that can occur around the knee and can mimic prepatellar bursitis. They can occur anywhere in the body, but more prevalent sites are the face, neck, trunk, behind the ears, and palmoplantar region. In the present case, a 52-year-old man with epidermal inclusion cyst presented to the surgery outpatient department (OPD) with symptoms clinically mimicking as prepatellar bursitis, occurring at a rather unusual site, ie; the anterior aspect of the left knee. The possibility of an epidermal inclusion cyst should always be considered in an atypical soft tissue mass when presenting around the knee. Histopathological examination confirms the diagnosis.

Accuracy of clinical diagnosis, imaging methods, and biopsy in tumours and pseudo-tumours of the hand.

The appropriate use of imaging methods in bone and soft tissue tumours of the hand is well established in the radiological literature. However, since most of the tumoral conditions of the hand are benign, the use of imaging methods may be based on clinician preferences and technical availability. The aim of this work is to present the experience in our institution in the management of tumours and pseudo-tumours of the hand and to review the utility of different imaging methods in their diagnosis. We present a retrospective and consecutive case series of patients referred to Hospital Universitario Virgen de las Nieves due to clinical suspicion of hand tumour in the last 10 years. We assessed the accuracy of clinical and imaging diagnoses, matching the final pathological or surgical results, considering a diagnosis as "correct" if it was included in the differential diagnosis suggested in the clinical (including all provided diagnoses) or radiological report (only the first 2 diagnoses), respectively. Biopsy accuracy was contrasted with surgical findings. We included 175 patients with a pathological or microbiological diagnosis of hand tumors, obtained through surgery (n=124) and/or core needle biopsy (n=62), or puncture-drainage (n=30). Among these, 21 cases were identified as infectious, metabolic, or inflammatory processes, while 154 were classified as hand tumours or pseudotumours (101 in soft tissues and 53 in bone). The overall diagnostic accuracy (95% confidence interval) for each approach was as follows: clinical diagnosis, 26.3% (19.8-32.8%); ultrasound, 72.6% (64.3-80.8%); magnetic resonance imaging (MRI), 80.6% (73.8-87.4%); computed tomography (CT), 84.6% (74.8-94.4%); and radiography, 46.8% (38.6-55.0%). The overall accuracy of imaging was 81.1% (75.3-86.9%). For soft tissue masses, the diagnostic accuracy was: clinical, 30.7% (25.5-42.1%); ultrasound, 69.8% (62.9-80.1%); MRI, 73.9% (65.5-83.4%); CT, 75.0% (30-92%); and radiography, 20.3% (14-33%), with an overall imaging accuracy of 75.2% (69.2-84.1%). For bone tumours, the accuracy was: clinical, 10.9% (5.2-21.8%); ultrasound, 75.0% (46.8-91.1%); MRI, 90.7% (78.4-96.3%); CT, 92.3% (79.7-97.3%); and radiography, 83.3% (71.3-91%), with an overall imaging accuracy of 89.1% (78.2-94.9%). Biopsy accuracy was 90.7% (83-98.5%) overall, 86.4% (74-98%) for soft tissue masses, and 100% (81.5-100%) for bone tumours. Imaging outperforms clinical diagnosis in terms of accuracy and should be mandatory before any interventional procedure. Imaging-guided biopsy is an efficient complementary technique when doubts persist about the nature or potential malignancy of a hand tumour.

Angiomatoid Fibrous Histiocytoma Initially Misdiagnosed as Elastofibroma Dorsi: A Case Report and Literature Review

Background and Objectives: Angiomatoid fibrous histiocytoma (AFH) is a rare soft-tissue tumor with a low-grade malignancy. It typically arises in superficial soft tissues of the extremities, head, neck and trunk in children or young adults. Because of its rare entity, it tends to be confused and misdiagnosed. Materials and Methods: A 12-year-old male presented with a painless mass located on his right upper back. The CT finding showed a 7.3 × 2.8 × 5.4 cm-sized, well-defined heterogeneous soft tissue mass in the right infrascapular area. We performed a complete excision, including the surrounding capsule. Result: The final pathology revealed an AFH of intermediate malignancy. On pathologic examination, the lesion was a 5.8 × 4.5 × 2.6 cm-sized mass with a mitotic count of 12/10 HPF, tumor necrosis of 0% and marked increased cellularity and spindle cell morphology. The immunohistochemical study showed negative for S100 and positive for SMA, focal positive for Ki-67, CD68 and positive for CD99, Desmin staining. During the five years of follow-up period, he did not show any evidence of recurrence. Conclusions: The result was satisfactory. We report a case of AFH of the back initially misdiagnosed as an elastofibroma dorsi (ED) with the review of the literature for this uncommon entity.

Imaging manifestations and misdiagnosis of liposclerosing myxofibroma fumor

To focus on the imaging features of liposclerosing myxofibrous tumor (LSMFT) and diagnostic challenges to enhance clinical recognition and differential diagnosis accuracy. Retrospective analysis was conducted on the imaging and pathological data from 21 cases diagnosed with LSMFT between January 2014 and November 2022, including 14 males and 7 females (aged from 21 to 73 years; the course of disease ranged from 4 to 48 months). Patient demographics, clinical presentations, and imaging modalities including X-ray, CT, and MRI were reviewed. Pathological findings were correlated with imaging features to delineate diagnostic criteria and identify causes of misdiagnosis. All 21 patients represented primary lesions, located in 14 bilateral femurs [9 on the right and 5 on the left; 12 proximal femurs (intertrochanteric and peripheral) and 2 distal femurs], 2 proximal tibia, 2 proximal humerus, 1 proximal radius, and 1 ilium and 1 calcaneus. On X-ray and CT, all lesions showed cartographical or quasi-circular osteolytic destruction with distinct and sclerotic margins, continuous bone cortex, absence of periosteal reaction and surrounding soft tissue mass. Calcification, bone ridge and varying degrees of fat components were observed in 16 lesions, displaying mixed density;5 lesions showed ground-glass density with minimal bone ridge. On MRI, the signal intensity of the lesion was heterogeneous. T1-weighted imaging showed iso-to slightly high signal intensity, while T2-weighted imaging demonstrated unevenly high signal intensity. Fat-suppressed sequences depicted significantly elevated signal intensity within lesions, with post-contrast enhancement showing uneven patterns. 5 Cases were initially misdiagnosed as fibrous dysplasia. LSMFT is an uncommon benign bone tumor, typically localized in the proximal femur but occasionally found in other skeletal sites. Understanding its distinct imaging characteristics is crucial for accurate diagnosis. Typical cases exhibit identifiable imaging patterns, whereas atypical presentations may lead to misdiagnosis as fibrous dysplasia.

Uncommon Presentation of Multiple Myeloma: Pleural Effusion and Extensive Extramedullary Involvement

A 60-year-old female presented with abdominal pain, weight loss, and fatigue. Imaging revealed a pancreatic mass, bilateral pleural effusion, ascites, and lytic bony lesions. Investigations confirmed multiple myeloma with lambda light chain disease. Positron emission tomography-computed tomography (PET-CT) scan demonstrated extensive metabolically active soft tissue masses involving the pancreatic region, retroperitoneum, mediastinum, paravertebral regions, and multiple skeletal lesions with extraosseous soft tissue involvement, along with bilateral pleural effusions with metabolically active pleural and extrapleural deposits. The patient was initiated on a bortezomib, cyclophosphamide, and dexamethasone chemotherapy regimen with therapeutic thoracentesis for pleural effusion management. After two cycles, the patient showed remarkable clinical improvement. A repeat PET-CT scan revealed significant interval regression of soft tissue masses, metabolic activity resolution, and regression of pleural and extrapleural deposits. The extensive skeletal lytic lesions showed morphological stability but regression of associated metabolic activity and extraosseous soft tissue. This case highlights the potential of novel agent-based regimens in achieving exceptional responses in multiple myeloma patients with extensive extramedullary disease (EMD), including uncommon manifestations like pleural effusion. Early recognition and prompt initiation of appropriate therapy are crucial for improving outcomes in such cases.

3D-printed custom ankle braces for people with Charcot-Marie-Tooth disease: A pilot study.

Charcot-Marie-Tooth disease (CMT) is a neurodegenerative condition resulting in footdrop, ankle instability and impaired balance and gait. This study aimed to determine (1) whether 3D-printed custom ankle braces improve function and balance in people with CMT and (2) whether this is an acceptable device for use in this population. A within-subject comparison pragmatic/pilot study was undertaken. Ten people with CMT (mean [SD] age 48 [14] years, 60% male) were fitted with 3D-printed ankle braces. Following a 4-week wear-in period, walking and balance tests and patient-reported outcomes were assessed in two experimental conditions: (i) usual shoes and (ii) usual shoes with 3D-printed custom ankle braces. Differences in outcome measures between experimental conditions were analysed using linear mixed models. Comfort, aesthetics and overall satisfaction of the brace were assessed via 100-mm visual analogue scale (VAS). Adverse events and tripping/falls associated with the brace during the wear-in period were also recorded by participants using daily diaries. A significant improvement was seen during single-leg balance with eyes open (p=0.026, Cohen's d=0.55) and a significant reduction in foot pain (p=0.045, Cohen's d=0.82), with use of the ankle brace. Mean (SD) 100mm VAS scores were 62.7mm (17.9) for overall comfort and 73.9mm (21.2) for overall satisfaction. Subjective data from the daily dairies showed that one participant found the brace too firm around the ankle due to loss of soft tissue mass and two participants found it challenging to don and doff the brace due to loss of hand dexterity. This pilot study suggests that a 3D-printed custom ankle brace may improve balance and reduce foot pain in people with CMT; however, larger-scale trials are needed to further explore the impact of this brace on function and balance. Further customisation of the brace may also be required to improve acceptability for some people.

18 F-FDG PET/CT in Pediatric INI1-Negative Soft Tissue Myoepithelial Carcinoma.

A 12-year-old girl with no previous comorbidities presented with a left gluteal swelling. 18 F-FDG PET/CT demonstrated heterogenous, moderate hypermetabolism localizing to a very large pelvic soft tissue mass with extension through the left greater sciatic notch into the left deep gluteal space. Core biopsy of the mass revealed INI1-negative myoepithelial carcinoma. Here we report the molecular imaging findings in an extremely rare pediatric case of INI1-negative, soft tissue myoepithelial carcinoma.

Breast Metastasis From Sigmoid Adenocarcinoma Revealed by FDG PET/CT.

Breast metastasis from sigmoid carcinoma is rare. A 32-year-old woman, who had a history of sigmoid carcinoma, was found a hypermetabolic soft tissue mass in the left breast and a lymph node with moderate uptake on FDG PET/CT. Final pathology supported that the breast mass and lymph node were both metastases from the sigmoid carcinoma.

Hyperphosphatemic Familial Tumoral Calcinosis (HFTC) in a One-Year-Old Child: A Case Report and Literature Review

Introduction: Hyperphosphatemic Familial Tumoral Calcinosis (HFTC) is a rare autosomal recessive metabolic disorder characterized by abnormal phosphate regulation and soft tissue calcifications. Early diagnosis is crucial for optimal management to prevent complications. Case Presentation: A one-year-old child presented with intermittent fevers and a gluteal mass. Ultrasound revealed a calcified abscess, and biopsy confirmed a pseudocyst. Further workup identified elevated blood calcium, phosphorus, and neutropenia. The patient was ultimately diagnosed with HFTC. Discussion: Early diagnosis of HFTC is challenging due to the rarity of the disease and the potential for non-specific initial symptoms. This case highlights the importance of considering HFTC in the differential diagnosis for a young child with unexplained soft tissue masses or skeletal abnormalities, even outside the usual age range. Conclusions: This case report emphasizes the need for a high index of suspicion for HFTC in pediatric patients with suggestive clinical features, regardless of age. Early diagnosis and prompt intervention are essential to improve long-term outcomes and prevent complications.

FDG-PET/CT Avid Uptake of a Biopsy-Proven Aggressive Melanotic Schwannoma of the S2 Spinal Nerve Root

Abstract Background Malignant melanotic nerve sheath tumors (MMNSTs), also known as a melanocytic schwannoma (MS), are a rare type of peripheral nerve sheath tumors including Schwann cells with melanocytic differentiation. Only a few cases of spinal MMNST have been reported in literature. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) could be used to detect these lesions. Case Description A 70-year-old man with a 6-month history of backache was admitted to our hospital. PET/CT showed a paravertebral soft tissue mass along the spinal nerve at the S2 level with strong FDG uptake, and a nodule with increased FDG uptake in the right lobe of the left liver. A CT-guided biopsy of the S2 lesion was performed. The final diagnosis was spinal MS with hepatic metastasis. The patient received stereotactic body radiation therapy. Conclusion Herein, we report the PET/CT findings of a case of MS with hepatic metastasis. FDG-PET/CT is helpful in the differential diagnosis of benign and malignant lesions although nonspecific.

Sarcoma or haematoma? If only it was that simple! Part 2

Introduction: Imaging appearances and clinical presentation of soft tissue sarcoma and soft tissue haematomas are similar. It is imperative that sarcoma is differentiated from benign soft tissue lesions due to the poor outcomes and high morbidity associated with sarcoma. Topic Description: Part 2 of this pictorial review summarises the key ultrasound appearances of soft tissue sarcoma and soft tissue haematomas and some differential diagnoses. Discussion: Ultrasound is the first line test in the investigation of soft tissue masses. With the overlapping ultrasound appearances of soft tissue sarcoma and soft tissue haematomas, it is essential that practitioners are aware of key ultrasound appearances and understand when to escalate cases for further investigation. Conclusion: Sound knowledge of the clinical and sonographic features of soft tissue haematomas and soft tissue sarcoma as well as recognising potential differential diagnoses is fundamental to ensuring an accurate diagnosis, timely management and improved patient outcomes.

6424 From Hyperparathyroidism To Neurologic Crisis: A Tale Of Brown Tumor And Spinal Cord Compression

Abstract Disclosure: A. Kormanis: None. M. Anderson: None. M. McKnight: None. H. Darapu: None. Background/Objective: In this case, we present a rare and severe consequence of secondary hyperparathyroidism, a Brown tumor leading to spinal cord compression, in a young adult with end-stage renal disease. Case Report: A 26-year-old male with a medical history of polycystic kidney disease and IgA Nephropathy complicated by ESRD, history of brown cell tumors (s/p surgery) was admitted for hospitalization due to hypocalcemia after presenting to the Emergency Department with right lower extremity weakness. Examination revealed right hip flexor weakness and right foot clonus. Lab results showed serum calcium of 10.4 mg/dL . MRI displayed a 2.5cm X 3.7 cm soft tissue mass with circumferential encroachment of the epidural space leading to severe spinal canal stenosis of T4-T5 at the site of prior Brown tumor resection. Ultimately, the patient underwent subtotal parathyroidectomy with left cervical thymectomy, leading to an intra-operative PTH drop from >3500 to 247 pg/mL. Discussion: In the context of treating vertebral brown tumors, the consensus suggests that parathyroidectomy plays a crucial role in achieving both clinical and radiographical amelioration of the tumor. However, in cases like ours where paresis is present, surgical decompression of the tumor becomes imperative. Conclusion: The development of Brown tumors is a severe and rare long-term complication for hyperparathyroidism, and the location of a Brown tumor in the thoracic spine causing symptomatic cord compression is even more rare. Presentation: 6/2/2024

8081 Case report of sympathetic paraganglioma presenting as chronic catecholamine induced cardiomyopathy

Abstract Disclosure: Z. Tan: None. A. Taiwo: None. Background: Sympathetic paragangliomas are rare neuroendocrine tumors (<1/100,000) arising from extra-adrenal autonomic paraganglia, generally in the thorax, abdomen, and pelvis. They secrete catecholamines predominantly norepinephrine, which can cause a rare complication of catecholamine-induced cardiomyopathy. Clinical Case: A 33-year-old male, with history of obesity and borderline hypertension not on medication, presented with dyspnea on exertion, worsening paroxysmal nocturia dyspnea of 1 month duration and sudden onset of severe right flank pain. Work up for his chronic shortness of breath revealed: Troponin negative. EKG showed sinus tachycardia. Echocardiogram revealed enlarged left ventricle, severely decreased LV systolic function of 25-30%. Given the absence of angina symptoms, negative troponin, and EKG findings, his new-onset cardiomyopathy was presumed to be non-ischemic. CT chest, abdomen and pelvis was performed for the new onset right flank pain, which revealed a 4.1 cm x 4.0 cm centrally necrotic aortocaval soft tissue mass. This raise a concern about malignancy. A CT-guided Fine-Needle Aspiration of the retroperitoneal mass suggested paraganglioma. Further investigation showed plasma normetanephrine at 5.56 nmol/L (Reference range: 0-0.89 nmol/L), 24 hour urine normetanephrine at 2411 ug/d (Reference range: 114-865 ug/d), and 24 hour urine norepinephrine at 179 ug/d (Reference range: 14-20 ug/d). Plasma metanephrines and plasma dopamine were within the normal range. A gallium DOTATE PET/CT revealed a necrotic aortocaval mass with peripheral uptake, consistent with the known paraganglioma. He was diagnosed with sympathetic paraganglioma complicated with chronic catecholamine-induced cardiomyopathy and had exploratory laparotomy excision of his paraganglioma. Preoperatively, he was treated with phenoxybenzamine and carvedilol. However, his post-surgical course was complicated by acute on chronic heart failure and pneumonia, and he subsequently passed away from a pulseless electrical activity arrest. Conclusion: Although sympathetic paragangliomas rarely presents as catecholamine-induced cardiomyopathy, this case emphasizes the importance of considering hormonal abnormalities in patients who present with non-ischemic cardiomyopathy without high risk factors. Reference: 1. Alessandra Giavarini, Antoine Chedid et al. Acute catecholamine cardiomyopathy in patients with phaechromocytoma or functional paraganglioma. Heart 2013; 99: 1438-1444. Presentation: 6/2/2024

7388 Rare Case of Mediastinal Parathyroid Carcinoma

Abstract Disclosure: Y. Esaki: None. J. Moalem: None. A. Israel: None. I. Shafiq: None. Introduction: Parathyroid carcinoma accounts for 1% of primary hyperparathyroidism with an estimated prevalence of 0.005% of all cancers. Ectopic locations of parathyroid tumors have been found in 6-16% of cases, most commonly in the thyroid, the thymus, or behind the esophagus. Parathyroid carcinoma is rarely found in the mediastinum and only 30 cases have been reported in the literature. Clinical Case: A 68-year-old male without significant past medical history was evaluated by his primary care physician for constipation, polyuria and 20 lb weight loss over the past year. He presented to the hospital after blood work revealed serum calcium of 13.5 mg/dl (8.6-10.2 mg/dl). Initial hospital workup demonstrated serum calcium 12.9 mg/dl, phosphorus 2.6 mg/dl (2.7-4.5 mg/dl), 25-OH vitamin D 21 ng/ml (30-60 ng/ml), 1,25-(OH)2 vitamin D 143.0 pg/ml (19.9-79.3 pg/ml), PTH-related protein < 2.0 pmol/L (0.0-2.3 pmol/L) and PTH 1,250.0 pg/ml (15.0-65.0 pg/ml). CT scan revealed a 3.5 cm x 2.6 cm heterogeneous right paratracheal soft tissue mass with areas of calcifications with mass effect on SVC. Thyroid ultrasound showed multinodular thyroid tissues with a left 1.1 cm heterogeneous solid nodule along the mid posterior aspect as well as a 0.5 cm hypoechoic lesion inferior to the left lobe. Sestamibi scan demonstrated a large area of increased uptake corresponding to the mass seen in the superior mediastinum on CT imaging. He underwent neck exploration and left hemithyroidectomy as well as median sternotomy with resection of the paratracheal mass. Intraoperative PTH decreased from the baseline of 1,177.0 pg/ml to 65.6pg/ml following the removal of the paratracheal mass. The final pathology of right anterior mediastinal mass was consistent with a 5 cm parathyroid carcinoma with angioinvasion, intermediate lymphatic invasion, invasion into adjacent structures, and Ki67 proliferative index focally > 5%. His post-operative course was complicated by hypocalcemia, which improved with treatment with calcitriol and calcium supplementation. He declined the genetic testing. His calcium and parathyroid hormone have remained in the normal range after 1 year. Conclusion: This case illustrates a rare case of parathyroid carcinoma found in the mediastinum. It is important to recognize that parathyroid carcinoma can present in ectopic locations including the mediastinum, as this can affect the preoperative investigation and management. Fine needle biopsy (FNA) prior to the initial operation is not recommended as it is difficult to differentiate the parathyroid carcinoma from benign disease based on FNA, and it may cause tumor rupture and seeding. Also, in the mediastinal parathyroid carcinoma, localization of the lesions including the size and invasiveness is critical in order to allow for radical surgery. Presentation: 6/3/2024

6450 Leydig Cell Tumor: A Rare Cause of Post-menopausal Hyperandrogenism

Abstract Disclosure: R. Nakdali: None. S. Athimulam: None. Introduction: Ovarian steroid cell tumors are a rare subtype of sex-cord stromal tumors. Leydig cell tumors is a subtype of sex-stromal tumors that is found in < 1% of all ovarian tumors. They are typically benign, unilateral, and secrete androgens which causes virilization. Below we present the case of a postmenopausal woman who presented with signs of virilization and was diagnosed with an ovarian Leydig cell tumor. Case: A 62-year-old postmenopausal woman, with a history of partial hysterectomy with right oophorectomy presented to Endocrinology clinic for evaluation of thyroid nodules. However, clinically she had signs of virilization noted by the provider on examination. She reported progressive androgenic alopecia, cystic acne, oily skin, hoarseness of voice and hirsutism, with increase hair growth over upper lip, chin and jaw line requiring daily shaving. She denied taking any supplements. She reported embarrassment of these physical changes and prior providers had attributed this to aging, therefore not prompting further testing. This caused significant emotional distress to the patient, leading to isolation. Biochemical testing confirmed elevated bioavailable testosterone (193.1 ng/dL) and total testosterone levels (579 ng/dL), with no evidence of hypercortisolemia. Magnetic resonance imaging (MRI) revealed a heterogenous soft tissue mass (2.9 x 2.1 x 2.1 cm) in the left ovary. She underwent a left salpingo-oophorectomy and pathology confirmed a well-differentiated 2.4 cm Leydig cell tumor. Post-operatively, she reported improvement in facial and body hirsutism, reduced shaving frequency decrease in androgenic hair loss, with noticeable hair growth in her frontal scalp, and her skin became less oily with reduced acne. Post-operative labs confirmed cure of hyperandrogenism (Bioavailable testosterone < 2.6 ng/dL; Total testosterone: < 10ng/dL; and Free androgen index < 0.5%). She has been referred to genetics for evaluation. Discussion: Post-menopausal hyperandrogenism poses a diagnostic challenge as it can be mistaken for hormonal imbalances seen with aging. Often times, patients do not report symptoms due to embarrassment unless specifically addressed by provider. Initial testing consists of total and free testosterone and dehydroepiandrosterone sulfate (DHEAS) levels to assess the source of hyperandrogenism. Ruling out hypercortisolemia and assessment for ingestion of testosterone or DHEA supplements is vital. Pelvic ultrasound or cross-sectional imaging (CT or MRI) of abdomen and pelvis can identify structural abnormalities in the ovaries or adrenal glands. Prompt evaluation and management can alleviate significant distress to the patient. Leydig cell tumors represent a rare but important consideration in the differential diagnosis of postmenopausal hyperandrogenism, such as in our patient. Presentation: 6/2/2024

7999 Tumor Induced Osteomalacia Caused By Glomangiopericytoma

Abstract Disclosure: N. Kabir: None. E. Campbell: None. S. Singh: None. Introduction: Tumor induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused primarily by FGF-23 secreting tumors. Excessive production of FGF23 causes hypophosphatemia, decreased phosphate resorption in the gut, increased renal phosphate wasting, and decreased activation of Vitamin D. This leads to decreased bone density, bone pain, proximal muscle weakness, impaired gait, and recurrent fractures. Case Presentation: 44 year old male with a history of recurrent insufficiency fractures and weakness. At the time of evaluation, he reported fracture of tibial growth plate, sacral fracture, and metatarsal stress fracture. Other symptoms included bone pain, fatigue, muscle weakness, and intercostal muscle spasms with exertion. His pain was debilitating, requiring crutches to ambulate. Available labs at that time were significant for hypophosphatemia (1.3 mg/dL), elevated ALP (160 U/L), low 25OH-vitamin D (26 ng/mL), and normal calcium (8.7 mg/dL). Urine studies demonstrated phosphaturia (fractional excretion of phosphate, 62.4%). FGF23 level resulted at the upper limit of normal (210 RU/mL). Pending further evaluation, burosumab was started. Further work up included a 68Ga-PET-DOTATATE scan revealing a somatostatin receptor expressing soft tissue mass in the left sphenoid sinus and posterior left ethmoid sinus. The scan also demonstrated impending bilateral femur fractures, prior rib fractures, and sacral insufficiency fractures. Based on these findings, he was admitted to the hospital and underwent prophylactic, intramedullary nail fixation of his bilateral femur fractures. He underwent resection of skull base tumor with the final pathology revealing a sinonasal glomangiopericytoma. Immunohistochemical stain was positive for CD99 and cyclin D1, and focally positive for SMA, consistent with histopathologic diagnosis. Patient required prolonged inpatient rehabilitation to recover independent ambulation. Discussion: Sinonasal glomangiopericytoma (SNGP) is a mesenchymal tumor that accounts for <0.5% of all nasal and sinus tumors. TIO due to SNGP is extremely rare, with only a few cases reported since the 1990s. As seen with our patient, TIO from SNGP rarely presents with sinonasal symptoms, and can often be overlooked. Our patient hadb significant progression of disease and disability due to numerous delays in diagnosis and management. Definitive cure for TIO can be achieved with complete surgical resection of the tumor, but failure to diagnose in a timely manner can result in decline in quality of life. Our takeaway from this case is that providers should obtain FGF23 levels, especially in the setting of hypophosphatemia and phosphaturia, to complete the work up for osteomalacia. Presentation: 6/1/2024

6450 Leydig Cell Tumor: A Rare Cause of Post-menopausal Hyperandrogenism

Abstract Disclosure: R. Nakdali: None. S. Athimulam: None. Introduction: Ovarian steroid cell tumors are a rare subtype of sex-cord stromal tumors. Leydig cell tumors is a subtype of sex-stromal tumors that is found in < 1% of all ovarian tumors. They are typically benign, unilateral, and secrete androgens which causes virilization. Below we present the case of a postmenopausal woman who presented with signs of virilization and was diagnosed with an ovarian Leydig cell tumor. Case: A 62-year-old postmenopausal woman, with a history of partial hysterectomy with right oophorectomy presented to Endocrinology clinic for evaluation of thyroid nodules. However, clinically she had signs of virilization noted by the provider on examination. She reported progressive androgenic alopecia, cystic acne, oily skin, hoarseness of voice and hirsutism, with increase hair growth over upper lip, chin and jaw line requiring daily shaving. She denied taking any supplements. She reported embarrassment of these physical changes and prior providers had attributed this to aging, therefore not prompting further testing. This caused significant emotional distress to the patient, leading to isolation. Biochemical testing confirmed elevated bioavailable testosterone (193.1 ng/dL) and total testosterone levels (579 ng/dL), with no evidence of hypercortisolemia. Magnetic resonance imaging (MRI) revealed a heterogenous soft tissue mass (2.9 x 2.1 x 2.1 cm) in the left ovary. She underwent a left salpingo-oophorectomy and pathology confirmed a well-differentiated 2.4 cm Leydig cell tumor. Post-operatively, she reported improvement in facial and body hirsutism, reduced shaving frequency decrease in androgenic hair loss, with noticeable hair growth in her frontal scalp, and her skin became less oily with reduced acne. Post-operative labs confirmed cure of hyperandrogenism (Bioavailable testosterone < 2.6 ng/dL; Total testosterone: < 10ng/dL; and Free androgen index < 0.5%). She has been referred to genetics for evaluation. Discussion: Post-menopausal hyperandrogenism poses a diagnostic challenge as it can be mistaken for hormonal imbalances seen with aging. Often times, patients do not report symptoms due to embarrassment unless specifically addressed by provider. Initial testing consists of total and free testosterone and dehydroepiandrosterone sulfate (DHEAS) levels to assess the source of hyperandrogenism. Ruling out hypercortisolemia and assessment for ingestion of testosterone or DHEA supplements is vital. Pelvic ultrasound or cross-sectional imaging (CT or MRI) of abdomen and pelvis can identify structural abnormalities in the ovaries or adrenal glands. Prompt evaluation and management can alleviate significant distress to the patient. Leydig cell tumors represent a rare but important consideration in the differential diagnosis of postmenopausal hyperandrogenism, such as in our patient. Presentation: 6/2/2024