Malignant glomus tumor of the foot with obvious neuroendocrine differentiation: a with immunohistochemical studies

Abstract

Obvious neuroendocrine differentiation has not been reported in glomus tumor. The author herein reports a malignant glomus tumor of the foot showing obvious neuroendocrine differentiation. A 63-year-old woman presented with tumor of the left foot. The tumor was superficially seated, and located in the dermis. It was completely resected with wide margins. It measured 0.7 × 0.7 × 0.6 cm. Microscopically, the tumor was composed of atypical epithelioid cells located around blood vessel-like structures. The epithelioid cells showed relatively clear cytoplasm and severe cellular atypia, and resembled basal cell carcinoma. Focal areas of squamoid differentiation, carcinoid patterns, and neural differentiations were seen. There was no necrosis or atypical mitosis. However, mitotic figures were seen in 16 per 50 high-power-fields (HPF). The hematoxylin and eosin (HE) diagnosis was basosquamous carcinoma. Immunohistochemically, the tumor cells were strongly positive for vimentin, α-smooth muscle actin, and neuron-specific enolase. The tumor was focally positive for NCAM, synaptophysin and chromogranin. The blood vessel-like structures had a layer of CD31-and CD34-positive endothelial cells. Tp53 was positive and the Ki-67 labeling index was 23%. The tumor cells were negative for cytokeratin (CK) AE1/3, CK CAM5.2, CK5, CK6, CK7, CK8, CK14, CK18, CK19, CK20, p63, EMA, CEA, CA19-9, desmin, myoglobin, HMB-45, Melan-A, S100 protein, MUC1, MUC2, MUC5AC, and MUC6. Taken together with HE histology, the tumor was labeled as malignant glomus tumor with neuronal differentiation, based on the classification system of Folpe et al. The post-pathological diagnosis whole body examination using CT, MRI, PET, and endoscopies identified no tumors. The patient is now free from tumor and healthy 18 months after the resection.

Original paper Morphological and immunohistochemical profile of pancreatic neuroendocrine neoplasms

“…Coexpression of vimentin and neuroendocrine markers has also been reported in selected peripheral and visceral glomus tumours that show clear cell morphology [104,105], PNEN associated with tuberous sclerosis [106], and in 80% of renal NENs [107].…”

Primary squamous neuroendocrine carcinoma of the skin: A case report with immunohistochemical study

“…The positive S100 implies that the Langerhans cells (antigen presenting cells) are present in the carcinoma. Surprisingly, the SCC in the present case immunohistochemically showed broad neuroendocrine features, [18,19] and were positive for NSE (positive percentage (PP) = 70%), chromogranin (PP = 95%), synaptophysin (PP = 95%), and NCAM (CD56) (PP = 20%). The author hesitated in making the pathological diagnosis.…”

“…[17] NEC or NET is defined as epithelial tumors showing a broad neuroendocrine differentiation which is manifested as characteristic histological features and as immunohistochemical evidence of tumor cells for neuroendocrine tissue usually including chromogranin A, synaptophysin, CD56 (NCAM) and NSE. [18,19] SCC has never assumed features of NET, and vice versa in the literature.…”

Malignant glomus tumor of the thyroid gland: a case report

“…Malignant glomus tumors are usually located in the kidney 2 and foot, 3 but may sometimes occur at other sites in the gastrointestinal tract 4 or respiratory tract. 5 However, malignant glomus tumors occurring in the thyroid gland are rare.…”

“…The treatment options for malignant glomus tumors without a head and neck origin include complete surgical removal, radiotherapy, and chemotherapy. 1–5 One patient with a malignant glomus tumor of the kidney 2 received palliative radiation therapy and one cycle of gemcitabine, docetaxel, doxorubicin, and dacarbazine. However, the radiation therapy failed to improve the patient’s pain.…”