Neoodjuvant imatinib mesylate for advanced primary and metastactic/recurrent gastro-intestinal stromal tumour (GIST).

Therapy of gastro-intestinal stromal tumour (GIST) has changed significantly with the use of imatinib mesylate. Disease progression remains a complicated clinical issue, suggesting the need for multimodality management. This is a prospective clinical study evaluating the neoadjuvant use of Imatinib mesylate in primary GIST. There is pre-operative use of imatinib in 10 patients with operable advanced and metastatic GIST. The follow-up continued postoperatively for maximum period of two years and postoperative imatinib was given for two years. Ten patients were accrued in the study. Following imatinib mesylate therapy, the median reduction of tumour volume was 45% (range 20-60%). Six of the ten patients underwent complete resection of the tumour following neoadjuvant imatinib for a median period of three months, and are disease-free for a median follow-up of eleven months (range 6-24 months). Three patients in whom the tumours were deemed to be operable after downsizing and who refused surgery are also continuing imatinib. Imatinib did not produce serious toxicity in any patient.