Pelvic radiation therapy combined with hepatic artery chemotherapy for resected rectal carcinoma with liver metastases.

PURPOSE

Patients with hepatic metastases from rectal cancer treated with hepatic artery (HA) chemotherapy have a life expectancy great enough to be at risk for pelvic failure. Therefore, a treatment plan was developed for patients with resected rectal cancer and unresectable hepatic metastases, when the pathologic features of transmural invasion and perirectal lymph node metastases were present. Treatment consisted of concurrent pelvic radiation therapy (RT) and HA 5-fluorouracil (FUra), as systemic levels of FUra are achievable with HA administration, followed by HA fluorodeoxyuridine (FdUrd).

METHODS AND MATERIALS

Fifteen patients were offered combined pelvic RT and HA FUra. Radiation was given to an initial dose of 45 Gy to the pelvis, followed by boost treatment for an additional 5.4-10.8 Gy. Concurrent HA chemotherapy was given using FUra or FUra/leucovorin administered in two cycles of 14 days for each cycle. If HA chemotherapy could not be done, then intravenous FUra was given during RT. Following completion of RT and HA FUra, patients were evaluated for treatment with HA FdUrd.

RESULTS

Eleven patients received concurrent HA FUra or FUra/leucovorin and pelvic RT. Of these, six continued to receive HA FdUrd after completion of RT, as five patients were found to have progressive hepatic disease. Four patients could not have therapy as outlined, but did receive pelvic RT with concurrent intravenous FUra (two patients), FUra/leucovorin (one patient), or sequential HA FUra (one patient). There were four pelvic recurrences at 1, 4, 14, and 17 months after RT. One was the first site of progression, two occurred simultaneously with other failure, and one occurred after hepatic progression. The liver was the most frequent site of first progression (alone in seven patients; as a component of progression in four patients). Treatment was well tolerated with three Grade > or = 3 toxicities. The median survival was 14 months.

CONCLUSIONS

These data support the hypothesis that patients with metastatic rectal cancer are also at risk for pelvic recurrence. The frequency of hepatic progression supports continued aggressive therapy directed to this site. As systemic and regional therapy of metastatic rectal cancer improves, we anticipate that more patients will be at risk for a pelvic recurrence, making it increasingly important to explore the role of pelvic radiation therapy despite the presence of metastatic disease.