A histiocytic twist in a tale of GIST

Abstract

Histiocytic sarcoma (HS) is a rare, non-Langerhan's, malignant histiocytic neoplasm that occurs in lymph nodes and extranodal sites mainly the skin and intestine. Amidst the cases reported so far; majority of the cases previously diagnosed as HS have been Primary T cell lymphomas (PTCL). Cases primarily involving the extranodal sites are rare, with a confusing clinical picture and thus, are often misdiagnosed. Here we report a rare case of extranodal HS in a 54-year-old man, a previously treated case of gastrointestinal stromal tumor (GIST) of the stomach, who now presented with abdominal pain. On imaging, a growth was detected in the small bowel without accompanying lymphadenopathy.

A Rare Case of Histiocytic Sarcoma Secondary to Gastrointestinal Stromal Tumor in the Stomach: Transdifferentiation or Synchronicity?

“…Recently, there have been two case reports of HS together with GIST. One report of HS in the intestine occurred in a previously treated case of GIST in the stomach, following two years of treatment [ 28 ]. A second case report documented synchronous HS and GIST as a single gastric mass [ 29 ].…”

Histiocytic Sarcoma Secondary to Gastrointestinal Stromal Tumors: A Literature Review

“…Only three cases of HS and GIST have been documented thus far [ 38 - 40 ]. Two years following therapy, a patient with previously treated GIST in the stomach was found to have one case of HS in the intestine [ 39 ]. In another report, synchronous HS and GIST in the abdomen were described [ 40 ].…”