Sarcoma-like benign pelvic tumors: Three case reports

Abstract

Case reports Case 1 (proliferative fasciitis). A 2 l-year-old woman (para 1) noticed a tumor in the region of the perineum approximately six weeks previously. The tumor appeared to enlarge rapidly and become uncomfortable on sitting. There was no associated redness, tenderness, or abnormal discharge. Examination revealed a tumor about 5 cm. in diameter located midway between the labia majora and the pubic ramus in the area of the ischiorectal fossa. The tumor appeared to be fairly well circumscribed and not adherent to the skin or deep fascia. There was no fixation of the tumor and it appeared to have a solid consistency. The patient was admitted to the hospital for surgical removal. The tumor was dissected out of its space. There was no capsule or cleavage plane. The pathology on frozen section indicated a low-grade fibrosarcoma, and a decision was made to return the patient to her room and wait for permanent sections the following day. The permanent sections indicated a diagnosis of fibrosarcoma. The patient was again operated upon, and a wider dissection of the area was done, with removal of the contents of the ischiorectal space and the paravaginal area. Further consultation on the pathology changed the diagnosis to one of proliferative fasciitis. The microscopic slides of the tumor were sent to Dr. E. H. Soule’ at the Mayo Clinic who concurred in the diagnosis of proliferative fasciitis. He added this description: “The lesion is somewhat atypical in that it is more fibrogenic and there is a scarcity of proliferating capillaries. However, the advancing edge of the lesion into the fat together with the foci of loosely arranged proliferating fibroblasts is enough to substantiate the diagnosis.” Since that time, there have been many cases reported. Most of these cases involved the upper extremities, although other areas of the body, including the breast, may be involved. Terminology has not been consistent in the literature with the use of such terms as pseudosarcoma and fibromatosis. Nodular, infiltrative, and proliferative terms have been used in association with fasciitis. Chung and EnzingerZ suggest that the term proliferative fasciitis be reserved for this particular type of pseudosarcomatous process for it “underscores its kinship to both proliferative myositis and nodular fasciitis.” The rather rare location of our case is of interest. From case histories of this tumor, eight weeks is the average time of observation before patients seek medical care, which emphasizes the rapid growth characteristic of this tumor. Our case was observed for six weeks. Pregnancy or steroids are not particularly associated with this tumor although in our case it occurred approximately five months after pregnancy. Proliferative fasciitis has been characterized as a benign reactive proliferation of fibroblasts with a distinct microscopic pattern that superficially resembles sarcoma. Chung and EnzingeP stated that the architectural pattern is irregular and lacks the herringbone pattern or the arrangement of cells in intersecting fascicles of fibrosarcoma. Variable numbers of inflammatory cells may be present, although these lesions have been cultured both aerobically and anaerobically and no bacteria have been found. Proliferating endothelial cells forming small vessels are a prominent part of the histologic pattern, usually around the periphery of the tumor. The presence of many mitoses is a sine qua non not of malignancy but of accelerated proliferation.