Cutaneous Metaplastic Synovial Cyst

Abstract

with a swelling on the left side of his forehead that had been ongoing for 10 months. A clinical examination showed a subcutaneous, mobile and non-tender swelling. He had a past history of a similar swelling at the same site, which had been operated on four years previously at another hospital. No reports were available regarding the nature of this previous swelling. At presentation, the swelling was diagnosed clinically as a recurrent dermoid cyst and was excised and sent for histopathological examination. The pale grey firm nodular mass (1.2 x 1.0 x 0.8 cm) showed a solid cystic mass when sliced. An irregular cyst lined by hyperplastic synoviocytes forming broad villi and papillae with hyalinised cores infiltrated by lymphocytes and plasma cells was observed on microscopic examination [Figure 1]. Foci of chond

Painless Mobile Nodule on the Shoulder

“…In a literature review of CMSC cases performed by Fukuyama et al, 3 distribution of reported cases according to body site varied; however, limbs were found to be the most commonly involved area. A PubMed search of articles indexed for MEDLINE as well as a Google Scholar search using the term cutaneous metaplastic synovial cyst revealed at least 37 cases reported in the English-language literature, [3][4][5][6][7][8][9] including our present case. The pathogenesis remains uncertain; however, a majority of previously reported cases of CMSC characteristically have been associated with a pre-existing lesion, with most presentations developing at surgical scar sites secondary to operation or trauma.…”