Cytomorphological features of glomus tumors arising in the stomach: A series of two cases diagnosed on FNA

Cytologic analysis of a glomus tumor in the left second toe: Case report

We present a 66-year-old female with a glomus tumor diagnosed by fine-needle aspiration (FNA) at the subungual region of her left second toe. Cytologic findings include cohesive clusters of round, uniform cells with scant cytoplasm. Nuclei were monotonous with fine chromatin. No cellular atypia, nuclear inclusions, mitotic figures, nor nucleoli were identified. Cells were surrounded by thick wisps of magenta colored myxoid material reminiscent of a pleomorphic adenoma. Few spindle shaped cells could be seen near the border of the tumor clusters. Staining was positive for alpha-smooth muscle actin. This case report presents one of few FNA diagnosed glomus tumors.

Gastric glomus tumor diagnosed by fine needle aspiration of the stomach: A report of two cases and review of the literature

Glomus tumors make up 1% of stromal tumors of the stomach. Radiologic diagnosis of glomus tumors can be challenging as they share imaging characteristics with other neuroendocrine tumors and gastrointestinal stromal tumors. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has been reported as a useful method for the evaluation of gastrointestinal lesions. We report two cases of gastric glomus tumors in which EUS-FNA diagnosis was challenging. Cytologically, neoplastic cells were round to oval, uniform, bland appearing epithelioid cells with delicate chromatin and inconspicuous to vague nucleoli. Both samples lacked worrisome features such as high nuclear grade, high mitotic rate, and necrosis. Neoplastic cells were negative for Cam5.2 and AE1/AE3 with focal expression of synaptophysin in one of the cases. A definitive diagnosis was not made based on FNA. Familiarity with glomus tumors in the GI system and procurement of adequate material for cell block allowing the use of immunohistochemistry may allow an accurate preoperative diagnosis.

Glomus tumour of the iris: A case report

INTRODUCTION

Glomus tumours are rare benign tumours formed by modified smooth muscle cells arising from the glomus body. Glomus tumours occurring in the iris have not been previously reported.

CASE DESCRIPTION

A 32-year-old woman presented with a 9-day history of blurred vision in her right eye. Ultrasound, computed tomography and magnetic resonance imaging confirmed the presence of a mass lesion within the iris. Surgery of the iris was performed and the tumour was removed. Histopathological analysis confirmed a glomus tumour. The patient remains clinically stable 5 months following surgery and has experienced no tumour recurrence.

CONCLUSION

The findings from this case suggest that the typical symptoms of a glomus tumour may be absent in some cases, and that imaging examinations can help in understanding the extent of the lesion and the involvement of adjacent structures. Moreover, pathology and immunohistochemistry are crucial to confirm the diagnosis.

Gastric glomus tumor with a preoperative diagnosis by endoscopic ultrasonography-guided fine needle aspiration: a case report

A gastric glomus tumor (GGT) is a rare gastric submucosal tumor that can become malignant. A preoperative diagnosis would allow for a more informed decision regarding the treatment strategy. We present the case of an asymptomatic man with a GGT that was diagnosed during a preoperative examination. Upper gastrointestinal endoscopy was performed in a 64-year-old man and revealed a submucosal tumor at the lesser curvature of the antrum of the stomach. Endoscopic ultrasonography showed a 12-mm-sized hypoechoic tumor in the second and third layers of the stomach wall. A histologic diagnosis of GGT was made using endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA). Abdominal contrast-enhanced computed tomography was performed, but the identification of the tumor was difficult owing to poor enhancement. The gradual growth of the tumor made it necessary to perform an operation. Laparoscopy and endoscopy cooperative surgery was performed without any complications. The tumor cells were immunohistochemically positive for alpha-smooth muscle actin, h-caldesmon, and collagen type IV but were negative for desmin, discovered on GIST-1, S-100 protein, cluster of differentiation 34, epithelial membrane antigen, and cytokeratin AE1/AE3. The final diagnosis was identical to the preoperative diagnosis made using EUS-FNA. EUS-FNA is a useful method for the preoperative diagnosis of small submucosal tumors, including GGTs.

Mesenchymal neoplasms of the tubular gut and adjacent structures: experience with EUS-guided fine-needle aspiration cytopathology

INTRODUCTION

Unlike epithelial malignancies, mesenchymal neoplasms arising within the tubular gut are less often encountered in endoscopic ultrasound-guided (EUS) fine-needle aspiration biopsies (FNABs). Nonetheless, preoperative diagnosis of such neoplasms has important therapeutic and prognostic value. We report our experience with this category of neoplasms from the past decade.

MATERIALS AND METHODS

We performed a 10-year retrospective search at our respective institutions to identify EUS-guided FNAB cases of mesenchymal neoplasms arising from the tubular gut wall and closely adjacent structures. Cytopathologic diagnoses were compared to corresponding surgical pathology (SP) when available. Cases with either no confirmatory cell block (CB) immunohistochemical (IHC) staining, or no SP were excluded.

RESULTS

Two-hundred eighty-two cases (M:F = 1:1; age range: 25-94 years, mean age = 60 years) of EUS-guided FNAB from the tubular gut met our criteria. Onsite adequacy was performed on nearly all cases. Case numbers: 209 gastrointestinal stromal tumors (GIST), 58 smooth muscle neoplasms, and 15 miscellaneous neoplasms. Of these, 188 (67%) had SP follow-up. We found that 258 (91%) aspirates had a correct specific diagnosis, 3 (1%) were nondiagnostic, 18 (6%) had indeterminate diagnoses, and 3 (1%) had incorrect diagnoses (2 leiomyosarcomas mistaken as leiomyoma, and 1 fibrosclerotic lesion mistaken as inflammatory pseudotumor). Of 94 cases with no SP, all had a specific cytologic diagnosis based on confirmatory IHC staining from the CB including 61 GISTs, 29 smooth muscle neoplasms, and 4 miscellaneous tumors.

CONCLUSION

This study endorses the clinical utility of EUS-guided FNAB in the diagnosis of tubular gut mesenchymal neoplasms. A definitive and accurate diagnosis is possible in over 90% of cases, chiefly when cytomorphology is coupled with optimal cellularity and IHC from a concurrent CB. EUS-guided FNAB diagnosis of mesenchymal tubular gut neoplasms may play an important role in determining neoadjuvant therapy as targeted therapy evolves.