{'fraction_non_alphanumeric': 0.023634881825590873, 'fraction_numerical': 0.013854930725346373, 'mean_word_length': 5.635135135135135, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Epithelioid sarcoma masquerading as perforating granuloma annulare

Sir : Epithelioid sarcoma (ES) is a distinctive type of slowgrowing neoplasm that preferentially occurs on the distal upper extremities of young adults. It is well known that ES may mimic several benign lesions, both clinically and histologically. In particular, welldocumented cases simulating fibromatosis or isolated necrobiotic granuloma have been previously reported. We describe for the first time a peculiar microscopic variant of ES, masquerading as perforating granuloma annulare. A 50-year-old man had a year’s history of pain and swelling in his right thenar eminence, thought to be Dupuytren’s disease. He was surgically treated for this in another hospital, but multiple ulcers appeared in the same site within a year. He was first admitted to our hospital in November 1989. On admission, physical examination disclosed several punched-out indurated lesions in his right hand and forearm (Figure 1), microscopically diagnosed as perforating granuloma annulare. In March 1991, the presence of metastatic axillary lymph nodes warranted an amputation of the right upper extremity, along with a right axillary lymphadenectomy. The surgical specimen was histopathologically diagnosed as epithelioid sarcoma. On August 1995, the patient developed lung metastasis and underwent right bilobectomy. There is no evidence of disease 14 months after pulmonary surgery. Grossly, the amputation specimen showed multiple ulcers with indurated margins, measuring up to 20 mm. The cut surfaces had a glistening white appearance. Microscopically, the most striking feature was the presence of multiple coalescent nodules with central necrosis, surrounded by palisading eosinophilic epithelioid cells with minimal pleomorphism. Some of the nodules merged imperceptibly with areas of spindleshaped cells, in which mitoses were occasionally found. The lesions were mostly located in papillary dermis, but there was extension to subcutaneous fat or skeletal muscle. The central necrotic area of the most superficial nodules perforated the epidermis. The shaft of expanded hair follicles was occupied by aggregates of necrotic tumour cells, which eventually exhibit transepithelial elimination (Figure 2). Immunohistochemical stains for vimentin, cytokeratin (CAM5.2) and epithelial membrane antigen (EMA) were diffusely positive in the cytoplasm of tumour cells. Histopathology 1997, 31, 102–103