Real-life STUMP pathology reports (second and third opinions)
Some basic definitions and links have been added, while names of doctors and labs have been removed.
Surgical pathology report 1
This is a challenging case.
The sections show a myometrial smooth muscle neoplasm with no nuclear atypia and zero mitotic figures per ten high-power fields (50 high power fields counted).
The most concerning feature, however, is the presence of abundant necrosis with abrupt transitions between viable and necrotic cells, ghost tumor cell outlines:, and perivascular spacing. Other areas have an appearance suggesting an infarct [Tissue death because of an interrupted blood supply], however, with a hyalinized [glassy or transparent appearance] zone surrounding the necrosis.
Given the presence of ambiguous necrosis, I would regard this tumor as a smooth muscle tumor of uncertain malignant potential (STUMP), and would recommend close clinical follow-up.
Due to the difficult nature of this case, I have shared it with my colleague [doctor name], who concurs with the above interpretation.
Surgical pathology report 2
Sections of uterus have a benign endometrium without evidence of glandular hyperplasia or neoplasia. Sections of the myometrial mass have extensive hemorrhagic necrosis. Collections of bland spindled nuclei focally arrange themselves in Verocay body-like formations. There is no associated nuclear pleomorphism. No mitotic figures are identified.
The interface with the subjacent myometrium is smooth without areas of infiltration. The differential diagnosis in this case would include an infarcted leiomyoma as well as an infarcted smooth muscle tumor of low malignant potential. A smooth muscle tumor of low malignant potential is favored given the current subclassification of so-called uterine stump (smooth muscle tumor of uncertain malignant potential). The smooth muscle tumor of low malignant potential is characterized by none to mild atypic, loss than ten mitoses [cell divisions] per ten high-power fields [magnification level under a microscope], and tumor cell necrosis [cell death]. As noted above, tumor cell necrosis is prominent in this case.
Of such cases in the literature four of 15 recurred. Material from this case had been previously referred to [major pathology lab]. Their favored diagnosis was one of a smooth muscle tumor of uncertain malignant potential. A pertinent reference in this regard would include Phillip, PC IP et al. Uterine smooth muscle tumors other than the ordinary leiomyomas and leiomyosarcomas: a review of selected variants with emphasis on recent advances and unusual morphology that may cause concern for malignancy. (Adv Anat Pathol. 2010 Mar;17(2):91-112)