[Gastric stromal tumors. Results of a multicenter study. French Associations of Surgery Research]

Gastric stromal tumours are not perfectly known. The aim of this retrospective multicenter study (29 centers) was to improve knowledge of these tumours.

From 1986 to 1994, 159 patients were operated on for leiomyomas (50), leiomyosarcomas (24), malignant/benign schwann cell tumours (10/29), automatic nerve tumours (4), leiomyoblastomas (28), spindle cell tumours (14). The mean duration of follow-up was 5 years. Presenting symptoms, diagnostic procedures, operative and pathological findings, evolution (recurrence, death) were recorded for each patient.

Gastrointestinal bleeding and epigastric pain were the most common presenting symptoms (54% and 50% of patients, respectively). Endosonography was the most sensitive examination (97%). Malignant tumours size was greater than benign tumours size (12.6 cm versus 5.2 cm). Extension to contiguous organs or metastases were frequent (33% and 26% of patients, respectively). In 16 patients, pathological examination could not differentiate between malignant and benign tumour. Seven patients who had been operated on for a benign tumour (6%) developed a local (n = 4) or a metastatic (n = 3) recurrence. The 5-year survival rate was 40% for leiomyosarcomas, 28% for schwannosarcomas and 90% for malignant leiomyoblastomas.

The main feature of stromal gastric tumours is the frequent difficulty to differentiate between malignant and benign tumours. The prognosis of malignant tumours depends on pathological types. The prognosis of benign tumours is uncertain since recurrences may develop.