Israel Medical Association Journal

Background: The diagnosis of gastrointestinal stromal tumors is based on documentation of c-KIT and platelet-derived growth factor-alpha receptors or specific c-KIT mutations. Before the diagnosis of GIST[1] was possible, all cases had been classified as sarcomas or benign tumors.

Objectives: To identify cases of GIST formerly diagnosed as abdominal or retroperitoneal mesenchymal tumors.

Methods: We reviewed the archive material on all surgical cases diagnosed as gastrointestinal related malignant mesenchymal tumors or GIST in our medical center during the last decade (1995–2004).

Results: Sixty-eight cases of retroperitoneal soft tissue sarcoma were identified. Thirty-eight were reconfirmed to be GIST, 19 were newly diagnosed as GIST (the hidden cases), 8 cases were re-diagnosed as mesenchymal tumors, and 3 cases of sarcoma remained sarcomas. Of all the GIST tumors, c-KIT-positive and PDGFRα[2]-positive tumors were more characteristic of primary gastric tumors, while c-KIT-positive and PDGFRα-negative tumors were found in the colorectal area. The c-KIT-negative and PDGFRα-positive cases were of gastric origin.

Conclusions: Any c-KIT-negative malignant mesenchymal mass located near the proximal gastrointestinal tract should also be stained for PDGFRα to differentiate between GIST and other soft tissue sarcomas. Practically, formerly diagnosed abdominal or retroperitoneal soft tissue sarcomas should be reviewed to identify patients with misdiagnosed GIST and thereby avoid future unnecessary and ineffective chemotherapy.

Background: The incidence of malignant musculoskeletal tumors during pregnancy is very low. The paucity of data precludes the drawing of solid conclusions regarding a standard approach.

Objectives: To summarize our experience treating 13 pregnant women with malignant soft tissue or bone tumors.

Methods: We conducted a retrospective analysis of 13 cases of patients with either soft tissue or bone sarcoma that developed or progressed during pregnancy or immediately after delivery.

Results: The clinical presentation of the tumors was either a growing mass and/or increasing pain and disability. Most of the masses were located in the lower part of the body and of considerable size. Treatment given during gestation was limited to wide excision of the mass in the 28th week of gestation in one patient. All the patients reported disease progression during gestation. Vaginal delivery was possible in eight patients with no complications, cesarean section was carried out in three women, spontaneous miscarriage occurred in one and termination of pregnancy was performed in one patient.

Conclusions: The diagnostic and therapeutic approaches should be tailored specifically in every pregnant woman in whom sarcoma is suspected.
 

Background: Imaging-guided core needle biopsy is a well-established technique for the diagnosis of bone and soft tissue tumors and tumor-like lesions in specialized orthopedic oncology centers.

Objective: To present our results of computed tomography-guided core needle biopsy with assessment of the accuracy of the technique.

Methods: Between July 1998 and October 2000, 215 CT-guided core needle biopies were performed and histologically examined in the Unit of Bone and Soft Tissue Pathology, Tel Aviv Sourasky Medical Center. There were 80 soft tissue and 135 bony lesions. All biopsies were performed by the same radiologist and the histologic examination by the same pathologist.  To assess the accuracy of the procedure, we compared the diagnosis at biopsy with the diagnosis after definitive surgery (when available).

Results: Bone core needle biopsy (n = 135) showed malignancy in 89 cases (primary or recurrent bone sarcoma, lymphoma, myeloma, metastatic carcinoma or melanoma). There were 29 benign lesions. In 17 cases the result was inconclusive and an open incisional biopsy was performed. Of the 80 soft tissue biopsies, 35 were malignant (25 soft tissue sarcomas, 6 lymphomas, 4 metastatic carcinomas); 40 were benign (myositis ossificans, neurofibroma, desmoid tumor, schwannoma, hematoma and others), and 5 were inconclusive and followed by an open incisional biopsy. The core needle biopsy histologic diagnosis was compared with that of the definitive surgery and the diagnostic accuracy was 90%. Only three samples initially diagnosed as benign turned out to be malignant. No significant complications occurred during the procedures.

Conclusions: CT-guided CNB[1] of musculoskeletal lesions is a safe and effective procedure that assures sufficient and proper material for histologic examination. The accuracy of this method in our center was 90%. Tumor sampling is extremely important, especially in soft tissue sarcomas, and cores should be taken in different directions, including areas of necrosis. The processing is quick, especially for bone CNB, and diagnosis can be achieved within 24 hours. The material undergoes excellent fixation and the immunostains are reliable.