Three additional cases of non-neural granular cell tumor with novel immunohistochemical findings

Perineural Infiltration: A Comprehensive Review of Diagnostic, Prognostic, and Therapeutic Implications

ABSTRACT

Perineural infiltration refers to a neoplastic cell involvement in, around, and through the nerves. It is considered as one of the neoplastic dissemination pathways. Thus, its identification is crucial to establish the prognosis of some malignant skin neoplasms, such as squamous cell carcinoma, and explains the locally aggressive behavior of cutaneous neoplasms, such as microcystic adnexal carcinoma. We have conducted a review of malignant and benign skin tumors in which perineural infiltration has been described, and we also discuss some histopathological findings that may simulate perineural infiltration.

Case report: Abrikossoff's tumor of the facial skin

Abrikossoff tumors, also known as granular cell tumors (GCT), originate from Schwann cells. The most common location is in the oral cavity, followed by the skin, but they can also be found in the breast, digestive tract, tracheobronchial tree, or central nervous system. They can affect both sexes at any age, with a higher incidence between 30 and 50 years and a slight predisposition for female sex. They are usually solitary tumors but may also be multifocal. Most of the time, they are benign, with malignancy being exceptional in <2% of cases. Clinically, they appear as solid, well-defined, painless tumors, located subcutaneously with dimensions that can reach up to 10 cm. The definitive diagnosis is based on the immunohistochemical examination, and the treatment for benign tumors consists of surgical excision. Chemotherapy or radiotherapy may be required for malignant lesions, but the treatment regimens and their benefits remain unclear. This manuscript presents the case of a 12-year-old girl with a benign GCT, located in the skin on the mandibular line.

Dermatofibroma-like dermal non-neural granular cell tumor

Non-neural granular cell tumor (NNGCT) is a rare tumor with uncertain lineage. It presents as an asymptomatic polypoid or plaque-like lesion, especially on trunk. Because the granular cells are usually strongly reactive with S-100 stain, conventional granular cell tumors (GCTs) are regarded as those of neural or Schwann cell origin. Unlike GCTs, NNGCT is not reactive for S-100 protein and is thought to derive elsewhere, presumably from mesenchymal stem cells. A 20-year-old woman presented with a solitary, dermatofibroma-like, brownish nodule on her right arm. The lesion developed 3 months before presentation without subjective symptoms. Histopathologic examination revealed a grenz zone overlying a poorly circumscribed tumor extending through the reticular dermis. The tumor cells were large and polygonal, and they had numerous eosinophilic small granules in the cytoplasm. Immunohistochemical stains were positive for CD68, vimentin, factor XIIIa, CD10, and cyclin D1. Stains for S-100 protein, neuron-specific enolase, and CD34 were negative. Based on these findings, the lesion was diagnosed as dermal NNGCT.

Dermal nonneural granular cell tumor: a case report

Dermal nonneural granular cell tumor is a rare neoplasm of uncertain histogenesis that Le Boit and colleagues originally described in 1991. It arises commonly from the back, extremities and head and neck. To the best of our knowledge, only 50 cases have been reported in adults in the English literature. A 42-year-old man presented with a polypoid skin nodule of the front side of the chest wall, measuring 1,8 × 1,5 cm. The lesion was removed completely with tumor-free margins. Microscopically, the tumor was composed of a diffuse infiltrate of polygonal cells, S 100 negatives, with abundant granular cytoplasm and vesicular nuclei. The diagnosis of dermal nonneural granular cell tumor was retained. No recurrence was noted during follow up of 6 months. The prognosis is good.

Immunohistochemical ALK Expression in Granular Cell Atypical Fibroxanthoma: A Diagnostic Pitfall for ALK-Rearranged Non-neural Granular Cell Tumor

ABSTRACT

Atypical fibroxanthoma (AFX) is a neoplasm that most commonly occurs on sun-damaged skin of the head and neck in elderly patients and that usually exhibits indolent clinical behavior with complete excision. The granular cell variant of AFX demonstrates overlapping histopathologic features with dermal non-neural granular cell tumor (NNGCT), which typically arises on the extremities of young to middle aged adults with rare reports of regional metastasis. A subset of NNGCT harbors ALK rearrangements and expresses ALK by immunohistochemistry. Here, we present 2 cases of granular cell AFX occurring on the scalp of males aged 73 and 87 with ALK expression by immunohistochemistry and no evidence of an ALK rearrangement on fluorescence in situ hybridization, representing a diagnostic pitfall for NNGCT.

Granular Cell Tumor: A Clinical Study of 81 Patients

INTRODUCTION

Although a granular cell tumor (GCT) usually develops on the skin or oral mucosa, it has been described in many other organs. GCT typically presents as a solitary tumor, but multiple lesions can occur. It has also been described in association with other diseases.

OBJECTIVES

To describe the clinical characteristics of cutaneous and oral mucosal GCTs and explore potential associations with other diseases.

MATERIAL AND METHODS

Retrospective study of patients diagnosed with GCT at our hospital between 1995 and 2019. The following information was collected from the patients' medical records: age, sex, number of GCTs, location, diameter, time to diagnosis, tentative clinical diagnosis, surgical margin status, recurrence, follow-up time, and associated diseases.

RESULTS

We detected 89 cutaneous or oral mucosal GCTs in 81 patients (43 women, 38 men) with a mean age of 40.21 years. The mean tumor diameter was 1.34cm. Five of the 81 patients (6.2%) had multiple GCTs, including noncutaneous tumors. Patients with multiple GCTs were on average younger than those with a single tumor (P=.004). There was only a single case of local recurrence and no cases of distant metastasis. None of the patients had associated diseases.

CONCLUSIONS

Most GCTs are benign and local recurrence is uncommon, even in patients with positive margins. Nevertheless, the possibility of multiple tumors affecting the skin, oral mucosa, or internal organs should be borne in mind, especially in young patients.