Background: With the intention to achieve tumor reduction and thereby increase R0-resection rate, preoperative radiochemotherapy is increasingly applied in locally advanced rectum cancer. Along with the advantages of prior therapy, a delay of surgical treatment occurs which might despite continuing therapy give way to local tumor progression or metastatic disease.
Patients and methods: Since 1993 we have treated locally advanced rectum carcinomas by preoperative radiotherapy according to a preoperative study protocol. We analyzed the incidence of local tumor progression or metastases during the 12 weeks of preoperative treatment. Hundred and fifteen patients with histologically proven primary rectum carcinoma without evidence of regional or distant metastases and endosonographically determined infiltration depth of stage T3 or more underwent preoperative radiochemotherapy between 3/1993 and 10/1999. Hundred and eight patients (88 times uT3 and (20 times uT4) have been operated and examined afterwards with respect to response to prior treatment. Before and after preoperative therapy, endorectal ultrasound was performed to evaluate local response. Distant metastatic manifestations were excluded by radiography and ultrasound scanning.
Results: A reduction of the infiltration depth was observed in 55 patients (51%). Tumor size remained unchanged in 50 patients (46%). Only 3 patients (3%) showed tumor growth in histological assessment. Fifty-seven patients (53%) showed no change in lymph node status after preoperative therapy, whereas lymph node metastases were detected in 11 patients (10%) who were judged uN0 preoperatively. We discovered metastases in 6 patients (6%) after preoperative therapy.
Conclusion: During preoperative therapy, tumor progress is not entirely evitable. Considering the lack of precision in pretherapeutic staging diagnostics, we conclude that delays due to therapeutic regimen are responsible for prognostic disadvantage in only a small number of patients.