Hyperfractionation in carcinoma of the cervix: tumor control and late bowel complications

A systematic overview of radiation therapy effects in cervical cancer (cervix uteri)

A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for cervical cancer is based on data from 1 meta-analysis and 34 randomized trials. In total, 35 scientific articles are included, involving 7 952 patients. The results were compared with those of a similar overview from 1996 including 34 024 patients. The conclusions reached can be summarized in these points: There are limited scientific data supporting that postoperative pelvic radiotherapy improves disease-free survival in early cervical cancer. No firm conclusion can be drawn. There is moderate scientific evidence that external beam radiotherapy combined with brachytherapy gives a similar disease-free and overall survival rate as radical hysterectomy in early cervical cancer. There is strong scientific evidence that concomitant radiochemotherapy improves disease-free and overall survival compared to radiotherapy alone in early cervical cancer. The NCI has recently published an announcement stating that cisplatin-based chemotherapy should be used concomitantly with radiotherapy in cervical cancer. No solid documentation for this statement can be found concerning locally advanced stages ( >IIB). There is a strong scientific evidence that cisplatin-based chemotherapy given concomitantly with radiotherapy is superior to concomitant chemotherapy with hydroxyurea. There is no scientific evidence to show that neoadjuvant chemotherapy followed by radiotherapy improves disease-free or overall survival compared to radiotherapy alone in patients with localized cervical cancer. There is moderate scientific evidence that high-dose-rate brachytherapy gives the same local control rate as low-dose-rate brachytherapy but with fewer rectal complications.

Long-term follow-up of RTOG 88-05: twice-daily external irradiation with brachytherapy for carcinoma of the cervix

PURPOSE

To evaluate the efficacy and toxicity of twice-daily external irradiation to the pelvis with brachytherapy for carcinoma of the cervix in a long-term follow-up study.

METHODS AND MATERIALS

This study was designed to administer twice-daily irradiation doses of 1.2 Gy to the pelvis, 5 d/wk. Radiotherapy also included one or two low-dose-rate intracavitary implants, to deliver a total minimal dose of 85 Gy to point A and 65 Gy to the lateral pelvic lymph nodes.

RESULTS

Eighty-one patients with clinical Stage IB-IVA carcinoma of the cervix were enrolled in this prospective, single arm, Phase I/II study. Hyperfractionated irradiation was completed in 88%. Brachytherapy was given in two implants in 46% and in one implant in 54%. Six patients had acute Grade 3 toxicities. The cumulative rate of Grade 3 and 4 late effects for patients with Stage IB2, IIA, and IIB disease was 7% at 3 years, 7% at 5 years, and 10% at 8 years. For patients with Stage III and IVA disease, the rate of late toxicities (Grades 3 and 4) was 7% at 3 years and 12% at 5 years. The site of first failure was in the pelvis in 41%, para-aortic or supraclavicular lymph nodes in 6%, and other distant metastatic sites in 14%. The absolute survival rate was 61% at 3 years, 48% at 5 years, and 45% at 8 years. The disease-free survival rate was 43% at 3 years, 38% at 5 years, and 33% at 8 years.

CONCLUSION

The results suggest that, combined with brachytherapy, hyperfractionated irradiation to total parametrial doses about 10% greater than doses administered with standard fractionation pelvic irradiation was tolerated and at least appears to be as effective as standard fractionation pelvic irradiation.

Long-term local control and survival after concomitant boost accelerated radiotherapy for locally advanced cervix cancer

Between 1989 and 1994, a prospective clinical trial tested the safety and efficacy of concomitant boost accelerated superfractionated (CBASF) radiotherapy for patients with locally advanced cervix cancer. CBASF radiotherapy included 45 Gy/25 fractions to the pelvis and a 14.4 Gy/9 fraction concomitant boost to the primary tumor, followed by brachytherapy for a total point A dose of 85 Gy to 90 Gy. The 22 patients of International Federation of Gynecology and Obstetrics stages IIIA-IVA who received CBASF radiotherapy now have a median follow-up time of more than 8 years. The 7-year actuarial rates of local control and overall survival are 81% and 36%, respectively. Serious late toxicity included bowel injury requiring colostomy in eight patients within 2.5 years after treatment, but no other severe toxicity was observed after longer follow-up intervals. The local control and survival rates achieved with CBASF radiotherapy were higher than those observed within a matched contemporaneous cohort of patients treated with standard radiotherapy alone at the same institution (p = 0.1 for local control, 0.09 for survival). The encouraging trend toward improved tumor control, tempered by the complication rate, suggests an opportunity to apply more sophisticated radiotherapy techniques that might sustain the favorable effects of dose intensification while mitigating the normal tissue toxicity.

Advanced cervical cancer

Several large, prospectively randomized clinical trials run by multi-institutional cooperative groups have established that the best treatment for advanced cancer of the cervix is primary radiotherapy with concurrent, cisplatin-based chemotherapy. In fact, patients with earlier stage cervix cancer with poor prognostic indicators (large, bulky tumors, positive pelvic lymph nodes, or unexpected parametrial disease at the time of surgery) also show a survival benefit with this approach. Adequate radiation dosing (both external beam and intracavitary) is essential. The additional benefit of periaortic lymph node irradiation is debated, but generally accepted, for patients with locally advanced disease or pelvic lymph node involvement.