Observations on the fine structure of interdigitating cell sarcoma.

In this histo-pathological follow-up study of a case of interdigitating cell sarcoma, intracytoplasmic membrane complexes were seen by electron microscopy within the neoplastic cells. These complexes might correspond to the eosinophilic inclusions seen in the tumour cells by light microscopy; they were not identified in the initial lymph node lesion. Recently, these structures have been found to be a variation of microtubuloreticular complexes. To our knowledge, they have not been previously described in interdigitating cell sarcoma. Their significance remains obscure.