Fine structure of endometrial stromal sarcoma

Abstract

A case of endometrial stromal sarcoma was studied and compared with early normal endometrium. It was concluded that a definite likeness exists between the ultrastructure of the endometrial stromal sarcoma and the cells of early endometriumthus suggesting an endometrial histogenesis of this tumor. Ultrastructural characteristics of other mesenchymal tumors are discussed.

Ultrastructure of endometrial stromal sarcoma

“…Cells with fibroblastic differentiation as seen in this tumor are similar to the superficial stromal cells in late proliferative and early secretory phase.16 I n view of the fact that most of the cells in this tumor closely mimic the structure o f normal stromal cells, it can justifiably be concluded that this tumor is probably derived from the endometrial stromal cells. This is in agreement with the findings of Komorowski et al 6 It has been suggested in the past that stromal sarcomas of the uterus are identical to hemangiopericytomas of other organ~.~JO Both tumors have a similar histologic appearance and an identical general architecture, characterized by a rich network of fine capillaries surrounded by closely packed, rather uniform tumor cells. A categorical distinction between hemangiopericytoma and stromal sarcoma would, therefore, depend on an ultrastructural differentiation between the cells comprising these tumors.…”

“…It was concluded that a definite likeness exists between the ultrastructure of endometrial stromal sarcoma and the stromal cells of early proliferative endometrium, thus suggesting an endometrial histogenesis of the tumor. 6 Electron microscopic studies of the stromal cells of endometrium have been sparse.6s16v1* Wienke et a1.16 have noted that the structure of stromal cells shows marked variation depending upon the phase of the menstrual cycle, Thus, during the early proliferative phase, the stromal cells are immature and resemble stem cells. During the latter part of the proliferative phase and early part of progestational phase, these cells gradually transform into cells resembling active fibroblasts and show evidence of collagen synthesis.…”

Endolymphatic Stromal Myosis of the Uterus With Metastasis to Ovary and Recurrence in Vagina

“…The entity endolymphatic stromal myosis, stromatosis or grade I endometrial stromal sarcoma has remained somewhat enigmatic over the past decades because of its benign histological appearance, in which the stromal cells lack significant atypism, pleomorphism, and mitosis ( PIVER et al, 1984) Ultrastructural studies utilizing electron microscopy have corroborated the similarities between the cells of ESM and those of the normal stroma of early-and mid-proliferative phase endometrium (AKHTAR et al., 1975al., : KOMOROWSKI et al, 1970. Classic cells in ESM are typical of the day 5 proliferative phase endometrial stromal element (MAZUR and ASKIN, 1978) and KUDO et al.…”