Pelvic intra-arterial mitomycin C infusion in previously treated patients with metastatic, unresectable, pelvic colorectal cancer and angiographic determination of tumor vascularity.

Thirty patients with unresectable pelvic tumors from recurrent or metastatic colorectal cancer, after failing all conventional chemotherapy or radiotherapy, were treated with mitomycin C (MMC) regional intra-arterial (IA) infusion. MMC at a dose of 20 mg/m2 in 100 mL of 5% dextrose in water was infused for a one-hour period through the regional artery (eg, hypogastric, gluteal) approached percutaneously via the femoral artery. This treatment was repeated every four to eight weeks. Of the 26 patients who could be evaluated, three had objective responses, 14 had tumor stabilization, and nine had no response. Median survival time for the responders (Rs) was 435 days, for stabilized patients (Ss) was 263 days, and for nonresponders (NRs) was 195 days, giving an overall survival time of 239 days. Fourteen patients (2 Rs, 8 Ss, and 4 NRs) had good relief of pain after the IA infusion. Thirty-three pelvic arteriograms (including three patients who had never received IA infusion) showed an avascular tumor of grade 0 in eight patients, a hypovascular tumor of grades 1 and 2 in 16 patients, and a vascular tumor of grade 3 in nine patients. Neovasculatures were mainly derived from the hypogastric artery or its branches (eg, gluteal, obturator, and pudendal artery), and occasionally were found to be derived from the superior hemorrhoidal, lumbar, and sacral arteries. The major side effect after the pelvic infusion was necrotizing cellulitis occurring in the buttock. Myelosuppression was manageable and other toxic effects were mild. Metastatic colorectal cancer occurring in the pelvis was basically a vascular-deficient tumor. Regional IA MMC infusion given intermittently was found effective in palliating pelvic pain and improving the quality of these patients' lives.