60Cobalt vs. linear accelerator in the treatment of locally advanced cervix carcinoma: a comparison of survival and recurrence patterns

Objective: To compare the survival and recurrence patterns of patients with locally advanced cervical carcinoma treated with 60cobalt radiotherapy units and linear accelerators.

Methods: Two hundred and forty-eight patients with cervical carcinoma stages IIB-IVA who were treated with primary irradiation between the years 1985 and 1988 comprised the study group. The median survival of patients treated with 60cobalt units and linear accelerators was calculated using the method of Kaplan and Meier and compared using the log-rank test. Recurrence patterns were compared using chi-square analysis; p < .05 was considered significant for all tests.

Results: One hundred and ninety-five patients were treated with 60cobalt units (Group 1) and 53 patients were treated with a linear accelerator (Group 2). Group 1 and 2 were similar with regard to mean age and weight, stage distribution, and mean dose to point A. The rate of recurrence was comparable between Group 1 and 2 (65.6% vs. 64.2%) and no significant difference was found in overall survival between the groups (20 months vs. 21 months. p = 81). There was a trend toward increasing pelvic recurrence in Group 1 (50.8%) compared to Group 2 (35.8%, p = .08).

Conclusions: 60Cobalt units and linear accelerators offer comparable rates of overall survival in patients with locally advanced cervix carcinoma.

Cervical carcinoma; 6°Cobalt; Linear Accelerator; Survival

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