Leiomyosarcoma of large and small veins: clinical findings and results of treatment in six patients.

Vascular leiomyosarcomas are rare malignant tumours originating from the media of the vessel wall. Six patients (five women and one man, aged 44-66 years) have been treated for a vascular leiomyosarcoma located in the inferior vena cava (three patients), the suprarenal, the external iliac and an antecubital vein. In four patients, the tumour was large and extended beyond the vessel wall giving rise to a retroperitoneal mass. In two patients the tumour was confined to the inner wall of respectively a large and small vein, occluding the lumen; the former was in the inferior vena cava and the latter in an antecubital vein. Block resection was performed in all patients. The tumours showed mitotic indices ranging from 6-32 mitoses/10 high power fields. The five patients with retroperitoneal tumours received additional radiotherapy varying from 50.00-70.00 Gy, on the basis of either macroscopic residual tumour or indefinite radicality. One of these five patients developed distant metastases within 2.5 years without local recurrence, the other four had no evidence of recurrence at follow-up, 3-7 years (mean 4.2 years) after surgery. The results illustrate the role of adjuvant radiotherapy in the control of local recurrence, when resection in this type of tumour proves to be either non-radical or totally radical.