A rare case of solitary fibrous tumor of the adrenal gland detected by (18)F-FDG PET/CT

A Woman With Persistent Abdominal Pain in the Setting of a Solitary Fibrous Adrenal Tumor

Background/Objective

We present a case of a woman with persistent abdominal pain, leading to the discovery of a rare solitary fibrous tumor (SFT) in the adrenal gland. The rarity of adrenal SFTs and their diagnostic challenges make this case noteworthy. The objective of this report is to describe a patient with an adrenal SFT, highlighting the unique diagnostic approach and management considerations for this rare condition.

Case Report

A 35-year-old woman presented with chronic abdominal pain and was referred to the endocrinology clinic for evaluation of an adrenal incidentaloma. Computed tomography imaging revealed a 4 cm homogeneous right adrenal mass, with precontrast Hounsfield units of 1 and an absolute contrast washout of 60%. A prior computed tomography scan from 6 years earlier showed a 1.5 cm adenoma with similar characteristics. Despite normal hormonal levels, the tumor's growth and the patient's symptoms prompted surgical referral. The patient underwent robotic-assisted laparoscopic right adrenalectomy. Pathological examination identified a well-circumscribed SFT, measuring 3.7 × 3.6 × 2.9 cm.

Discussion

Adrenal SFTs are rare, typically hormonally inactive, well-circumscribed masses that often present with abdominal pain. While more common in the pleura, adrenal SFTs can mimic other benign adrenal lesions on imaging, complicating diagnosis. Histopathology is essential for accurate diagnosis, and surgical resection remains the main treatment.

Conclusion

This case highlights the diagnostic challenges of adrenal SFTs, which can mimic other benign lesions. Despite significant growth, the tumor was histologically benign with low malignancy risk. Clinicians should consider adrenal SFTs in the differential diagnosis of incidental adrenal masses with atypical imaging features.

Solitary fibrous tumor of the adrenal gland: a case report and review of the literature

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor, probably of fibroblastic origin, mainly in the extremities and pleura. Primary SFT of the adrenal gland is clinically more rare. Here, we report the case of a 47-year-old woman who detected a left adrenal mass on physical examination, without any symptoms, and no laboratory abnormalities. A computed tomography (CT) examination of the adrenal gland suggested a round-like soft tissue density shadow in the left adrenal area. An unenhanced scan showed uneven density of the mass, with a scattered circular-like cystic low-density shadow inside, and an enhanced scan showed obvious uneven enhancement. We considered it to be adrenal pheochromocytoma. Ultimately, the patient was treated with laparoscopic left adrenalectomy. A pathological examination suggested an adrenal SFT. We reviewed previous case reports of adrenal SFTs and summarized the clinical characteristics of adrenal SFT combined with the relevant literature. For adrenal tumors with uneven low-density shadow and uneven CT enhancement features, we should consider the differential diagnosis of adrenal SFT.

Solitary Fibrous Tumor of the Bone Detected by FDG PET/CT

ABSTRACT

Solitary fibrous tumor as a rare mesenchymal tumor can occur in a wide variety of body sites, including serosal membranes, liver, lung, and deep soft tissues; however, primary tumor arising in bone is rarely documented. Herein, we reported the MRI, bone scan, and FDG PET/CT findings of a primary spinal solitary fibrous tumor in a 39-year-old woman.

Solitary Fibrous Tumor of the Adrenal Gland

OBJECTIVES

Solitary fibrous tumor (SFT) is a mesenchymal neoplasm that can arise at various anatomic locations. It is characterized by inv12(q13q13)-derived NAB2::STAT6 fusion, resulting in the nuclear expression of STAT6. Primary SFT of the adrenal gland is rare. We launched a multi-institutional collaboration to comprehend the overarching demographics, clinical and follow-up, macroscopic, microscopic, IHC, and FISH features of 9 patients with SFT of the adrenal gland.

METHODS

We added a series of 9 patients to the collection of adrenal SFTs where the clinicopathologic parameters, including clinical presentation, imaging, histopathology, IHC, molecular profiles, and management and follow-up data, were analyzed comprehensively. A modified 4-variable risk stratification model, including age, tumor size, and necrosis, was applied.

RESULTS

Our series consisted of 6 male and 3 female patients, ranging in age from 19 to 64 years (mean, 49.3 years). Abdominal pain (4) and fever with abdominal pain (1) were the presenting symptoms in 5 patients. In the remaining 4 patients, the tumors were detected by abdominal imaging for hypertension and diabetes. The size of the tumor ranged from 2 cm to 10.5 cm in maximum dimension. All tumors exhibited the morphology of a spindle cell SFT with a patternless architecture; 3 had a focal storiform arrangement. STAT6 positivity was observed in all tumors, and 7 were positive for CD34. Surgical resection was the primary modality of treatment. No adjuvant therapy was administered. Follow-up ranging from 7 months to 23 months was available for 7 patients. All were alive without disease recurrence or metastasis. Risk stratification placed 8 (88.9%) patients into a low-risk category and 1 into an intermediate-risk category.

CONCLUSIONS

This series is the largest of adrenal SFTs to date. These tumors of the adrenal gland are predominantly spindle cell neoplasms with indolent behavior, with a wide age distribution and a slight male preponderance. Combining our cohort with the previously published cases, the majority of tumors fall into the low-risk category for the propensity to develop metastases. Owing to the rarity and age distribution associated with these tumors, the differential diagnosis is wide and requires a systematic approach for ruling out key differential diagnoses aided by STAT6 IHC.

Solitary Fibrous Tumor of Adrenal Gland and Review of the Literature

Solitary fibrous tumor (SFT) is a rare and still controversial entity. This type of tumor first appeared in the literature as a pleural lesion, but, over the last decades, it has been reported in many extrathoracic sites. As a tumor of the adrenal gland, SFT is still rare and very uncommon, thus extensive research among the English language literature has been performed. We present here a case report of an adrenal SFT which is compared to 11 other known cases. Our case report is from a patient with SFT on the left adrenal gland, followed by mild symptoms of abdominal discomfort and hypertension. Physical examination, laboratory, and radiological tests were performed. The patient underwent surgery and the material was sent for histopathologic analysis for a definite diagnosis. Regular follow up appointments were performed over the course of two years. No recurrence of the tumor has been detected. We explain the symptoms, diagnosis, treatment, and additionally we describe the results and implications of the findings reported in the literature. Correct diagnosis is mandatory for optimal management of solitary fibrous tumor patients.

A Rare Case of Metastatic Solitary Fibrous Tumor (Hemangiopericytoma) of the Dura on 18F-FDG PET/CT

ABSTRACT

Solitary fibrous tumor is a rare neoplasm of mesenchymal origin. It can arise in various locations, most commonly in the pleura. It encompasses a heterogeneous group of histological patterns with different biological behavior. In some cases, metastases occur, sometimes years after the initial diagnosis. We report a case of metastatic meningeal hemangiopericytoma, also called solitary fibrous tumor of the dura, exhibiting liver metastases and muscle metastases 5 years after resection and adjuvant radiotherapy of the primary tumor.

Solitary fibrous tumor of the adrenal gland – its biological behavior and report of a new case

Introduction

A solitary fibrous tumor (SFT) is an uncommon neoplasm of mesenchymal and probably fibroblastic origin, occurring mainly in the extremities, and pleura. However, a primary involvement of endocrine organs is rare and even exceptional when found in the adrenal gland. Hereby, we describe the 10th report of an adrenal SFT.

Case presentation

A 77-year old man was diagnosed with a lesion in the right adrenal gland during a urologic indicated computed tomography (CT). No symptoms and laboratory anomalies were reported indicating any endocrine activity. Follow up CT-scans showed progressive growth of the nodule for which the patient underwent laparoscopic right adrenalectomy. Histological examination showed a hypercellular spindle cell neoplasm with elongated nuclei and a low mitotic index. The vessels were arranged in a hemangiopericytoma-like pattern with a slight sclerosing appearance. Immunohistochemistry showed a positive staining of neoplastic cells for STAT6, CD-34 and Bcl-2. Translocation analysis using RT-PCR showed no NAB2-STAT6 fusion. The specimen was confirmed as a hypercellular variant of an adrenal SFT.

Discussion

SFT is a rare neoplasm when occurring in the adrenal gland. Differential diagnosis can be broad because of no defined pathognomonic morphological characteristics. However, NAB2-STAT6 gene fusions are considered a molecular hallmark of SFTs. Therefore, STAT6 immunohistochemistry is a valuable diagnostic tool in differentiating between SFT and histologic mimics. After diagnosing SFT, its biological behavior is difficult to predict. SFTs are mostly benign tumors. Nonetheless, a histological benign-appearing SFT can show malignant clinical characteristics impeding assessment of proper follow up. However, malignancy has not been previously reported in any adrenal SFT case report.

18F-FDG PET/CT of a Rare Case of an Adenomatoid Tumor of the Adrenal Gland

A 28-year old man, with previous history of chronic abdominal pain, was referred to our nuclear medicine center for an F-FDG PET/CT following the fortuitous discovery of a 48-mm right adrenal gland lesion of heterogeneous density at the CT scan. The PET/CT showed an isolated heterogeneous significant uptake evocative of neoplasia. Surprisingly, the anatomopathological analysis after surgery revealed an adenoid tumor of the adrenal gland. This case of a rare benign tumor can be a source of false-positive and mimicking malignancies in the exploration of adrenal lesions.

A giant solitary fibrous tumor of the adrenal gland in a 13-year old: a case report and review of the literature

INTRODUCTION

Solitary fibrous tumors are tumors of mesenchymal origin that occur in the extremities and occasionally in pleura, meninges, and so on, but are extremely rare in the adrenal gland. Their biological behavior is variable but mostly benign.

CASE PRESENTATION

A 13-year-old Oromo girl presented with a progressively increasing right upper abdominal mass of 3 years' duration. She had dull dragging pain and an occasional low-grade fever. On examination she had 20 × 20 cm mass with well-defined medial and inferior border. Both ultrasound and computed tomography scan showed a highly vascularized mass arising from her right adrenal gland but she had neither the constitutional symptoms of a functional adrenal tumor nor an abnormal biochemical test. Surgical resection showed a vascularized mass with attachments to the right lobe of the liver with a weight of 1900 g. It was found to be a giant solitary fibrous tumor of her right adrenal gland with infrequent mitosis. She stayed for 5 days after surgery and was discharged. She showed remarkable recovery at follow-up at 3 months.

CONCLUSION

Although very rare, solitary fibrous tumor of the adrenal gland should be considered in differential diagnosis of adrenal masses.

Solitary fibrous tumor mimicking adrenal tumor concomitant with contralateral adrenal pheochromocytoma: A case report of surgical resection after long-term observation

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The management of bilateral adrenal masses is sometimes challenging.

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Adrenal mass was enlarged after contralateral adrenalectomy for pheochromocytoma.

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SFT is a rare cause of adrenal mass and its long-term natural history remains unknown.

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Surgical resection of SFT with partial adrenalectomy is a preferred choice.

Introduction

Solitary fibrous tumors (SFT) usually originate from the pleura and rarely occur in the retroperitoneum. There were few reports of SFT around the adrenal gland and its long-term clinical behavior remains unknown.

Presentation of case

A 62-year-old woman with bilateral adrenal tumors was referred to our department in 2008. She had elevated urinary normetanephrine. Metaiodobenzylguanidine scintigraphy showed uptake in the right adrenal gland. The tumor in the right adrenal gland was 5 cm in diameter. The patient underwent right adrenalectomy and was diagnosed with pheochromocytoma. The left tumor was 3 cm in diameter and diagnosed as benign using imaging. However, its size gradually increased to 10 cm over 7 years after surgery. The catecholamine hormones were within normal range. The patient underwent the tumor resection and left partial adrenalectomy. A steroid cover was given temporarily after surgery for prophylactic purposes. The histological diagnosis was solitary fibrous tumor. There was no recurrence 2 years after surgery.

Discussion

There have been only nine case reports of SFTs that were diagnosed as adrenal tumor by clinical imaging in the English literature. Total adrenalectomy was performed in all patients with a unilateral tumor. One patient with bilateral tumors underwent partial adrenalectomy.

Conclusion

SFT in the periadrenal region is difficult to differentiate from adrenal tumor. However, tumor resection with partial adrenalectomy should be considered for enlarged tumor with less aggressive behavior in patients with a history of contralateral adrenalectomy.

Magnetic resonance features of meningeal solitary fibrous tumors

The aim of the present study was to investigate magnetic resonance (MR) features of meningeal solitary fibrous tumors (SFTs) in order to improve their recognition. The study retrospectively analyzed MR manifestations in 12 cases of meningeal SFTs confirmed by surgery. The lesions were analyzed in terms of the site of their growth, growth mode, morphology, size, changes in the MR signal and the edge of the focus. The tumors were malignant in 3 cases, benign in 7 cases and borderline in 2 cases. A total of 3 cases spanned the tentorium cerebelli, 3 spanned the falx and another case was close to the falx. Overall, 4 superficial tumors were accompanied by adjacent bony destruction. One case was located at the triangular area created by the right lateral ventricles. The tumors were all lobular, with a large diameter and more cystic areas in the center of the focus. The signals were often heterogeneous. The parenchyma in the tumors was significantly enhanced. For certain tumors, the signal was usually inhomogeneous and not uniform. The MR features of a SFT were often similar to other intracranial tumors and easily misdiagnosed. There were certain innate characteristics, for example, the tumor was often a solitary large soft-tissue mass with an irregular edge and a clear boundary, with a lobulated contour, and was widely involved with other tissues. The tumors often grew across either the falx or tentorium cerebelli. A significantly inhomogeneous signal was found and either a low or low-high mixed signal on T2-weighted images in particular. These features are useful for the differential diagnosis of SFTs and other tumors.

The Pathologic Point of View of Laparoscopic Adrenalectomy in the Era of Radiologic Imaging: A Multicenter Retrospective Study

INTRODUCTION/AIM

This study aimed to determine if laparoscopic adrenalectomy (LA) is feasible for the treatment of adrenal malignancies and metastasis, and to review the final pathology findings in order to clarify the indications for surgery.

MATERIALS AND METHOD

The medical records of all patients that underwent LA at 3 university hospitals between January 1, 2008, and May 1, 2015, were retrospectively reviewed.

RESULTS

In total, 189 laparoscopic adrenalectomies were completed successfully. Mean duration of surgery was 79.3 ± 38.6 min and mean estimated intraoperative blood loss was 39.9 ml. Intraoperatively, 4 patients had major complications: spleen injury (n = 1), renal vein injury (n = 2) and diaphragm injury (n = 2). Histopathological examination showed that there were 20 different types of lesions. Surgical margins (SMs) were tumor free in 95.2% of the patients. Moreover, SMs were tumor free in all patients with adrenocortical carcinomas; however, positive margins were noted in 7 of 23 patients (30.4%) with malignant adrenal tumors.

CONCLUSIONS

The present findings support the use of laparoscopy for metastatic adrenal masses, despite a high positive margin rate. LA is a safe, feasible and cost-effective procedure for the management of benign and malignant adrenal masses.

Metabolic and anatomic characteristics of benign and malignant adrenal masses on positron emission tomography/computed tomography: a review of literature

PET/CT with (18)F-fluorodeoxyglucose (FDG) or using different radiocompounds has proven accuracy for detection of adrenal metastases in patients undergoing cancer staging. It can assist the diagnostic work-up in oncology patients by identifying distant metastases to the adrenal(s) and defining oligometastatic disease that may benefit from targeted intervention. In patients with incidentally discovered adrenal nodules, so-called adrenal "incidentaloma" FDG PET/CT is emerging as a useful test to distinguish benign from malignant etiology. Current published evidence suggests a role for FDG PET/CT in assessing the malignant potential of an adrenal lesion that has been 'indeterminately' categorized with unenhanced CT, adrenal protocol contrast-enhanced CT, or chemical-shift MRI. FDG PET/CT could be used to stratify patients with higher risk of malignancy for surgical intervention, while recommending surveillance for adrenal masses with low malignant potential. There are caveats for interpretation of the metabolic activity of an adrenal nodule on PET/CT that may lead to false-positive and false-negative interpretation. Adrenal lesions represent a wide spectrum of etiologies, and the typical appearances on PET/CT are still being described, therefore our goal was to summarize the current diagnostic strategies for evaluation of adrenal lesions and present metabolic and anatomic appearances of common and uncommon adrenal lesions. In spite of the emerging role of PET/CT to differentiate benign from malignant adrenal mass, especially in difficult cases, it should be emphasized that PET/CT is not needed for most patients and that many diagnostic problems can be resolved by CT and/or MR imaging.