Quality assurance in radiation therapy: clinical aspects

A systematic review of radiotherapy capacity in low- and middle-income countries

Objectives: The cancer burden in low- and middle-income countries (LMIC) is substantial. The purpose of this study was to identify and describe country and region-specific patterns of radiotherapy (RT) facilities in LMIC.

Methods: A systematic review of the literature was undertaken. A search strategy was developed to include articles on radiation capacity in LMIC from the following databases: PubMed, Embase, CINAHL Plus, Global Health, and the Latin American and Caribbean System on Health Sciences Information. Searches included all literature up to April 2013.

Results: A total of 49 articles were included in the review. Studies reviewed were divided into one of four regions: Africa, Asia, Eastern Europe, and South America. The African continent has the least amount of resources for RT. Furthermore, a wide disparity exists, as 60% of all machines on the continent are concentrated in Egypt and South Africa while 29 countries in Africa are still lacking any RT resource. A significant heterogeneity also exists across Southeast Asia despite a threefold increase in megavoltage teletherapy machines from 1976 to 1999, which corresponds with a rise in economic status. In LMIC of the Americas, only Uruguay met the International Atomic Energy Agency recommendations of 4 MV/million population, whereas Bolivia and Venezuela had the most radiation oncologists (>1 per 1000 new cancer cases). The main concern with the review of RT resources in Eastern Europe was the lack of data.

Conclusion: There is a dearth of publications on RT therapy infrastructure in LMIC. However, based on limited published data, availability of RT resources reflects the countries’ economic status. The challenges to delivering radiation in the discussed regions are multidimensional and include lack of physical resources, lack of human personnel, and lack of data. Furthermore, access to existing RT and affordability of care remains a large problem.

Radiotherapy alone in the treatment of uterine cervix cancer with telecobalt and low-dose-rate brachytherapy: retrospective analysis of results and variables

PURPOSE

This retrospective analysis aims to report results and variables from patients with cervix cancer treated by radiation therapy alone with telecobalt and low-dose-rate brachytherapy (LDRB).

METHODS AND MATERIALS

Between September 1989 and September 1995, 190 patients with histologic diagnosis of cervix carcinoma were treated with telecobalt for external beam radiotherapy (EBR), followed by one or two insertions of LDRB. Stage distribution according to patients was the following: IB, 12; IIA, 4; IIB, 105; and IIIB, 69. Median dose of EBR at whole pelvis was 40 Gy, and median parametrial doses for Stages II and III patients were 50 Gy and 60 Gy, respectively. Median doses of LDRB at point A for patients treated with one and two insertions were 38 Gy and 50 Gy, respectively.

RESULTS

Median follow-up time was 70 months (range: 8-127 months). Overall survival, disease-free survival, and 5-year local control of patients at Stages I, II, and III were 83%, 78%, and 46%; 83%, 82%, and 49%; and 92%, 87%, and 58%, respectively. Overall incidence of late complications in the rectum, small bowel, and urinary tract was 15.3% (19/190), 4.2% (8/190), and 6.8% (13/190), respectively. The actuarial 5-year rectal, small bowel, and urinary incidence of late complications was 16.1%, 4.6%, and 7.6%, respectively. Clinical stage was the only significant variable for overall 5-year survival (p = 0.001), for disease-free survival (p = 0.001), and for local control (p = 0.001). Stage II patients more than 50 years old had better disease-free survival and local control at 5 years (p = 0.004). None of the analyzed variables influenced the actuarial 5-year incidence of late complications.

CONCLUSIONS

Results of this series suggest that the use of telecobalt equipment for EBR with doses up to 50 Gy at whole pelvis, prior to brachytherapy, is an acceptable technique for radiation therapy alone in the treatment of cervix cancer, especially in developing countries, including Brazil, where telecobalt machines still prevail.

Situation of radiotherapy in Latin America

A survey to evaluate situation of radiotherapy in Latin America was conducted. Consultation was made with representatives of 10 countries, resulting in the responses of 5. These five countries represent around 80% and 81%, respectively, from the total area and population of South America. Situation of equipment, modern facilities, and human resources is analyzed. A Cobalt machine is the basic megavoltage equipment in Latin America; half of the total number, however, is of old units with very low output sources. Linacs represent one-third of cobalt machines, the majority of low photon energy without electron capability. Treatment planning, localization, patient positioning, and immobilization are inadequade or of low quality in a high number of institutions. Teaching programs are insufficient or inexistent in certain areas. Late diagnosis and referral for treatment is a major problem for cancer control in Latin America. Hierarchization and regionalization of radiation therapy centers are indicated as a way to provide high quality services and teaching programs. In Latin America, lodging and facilities for transportation are essential to assure the continuity of radiation treatment and regular follow-up to patients from rural or distant areas.

The treatment of stage III carcinoma of the uterine cervix with telecobalt irradiation

This is a retrospective analysis of 148 patients with histologically proven carcinoma of the cervix, stage III, treated with irradiation. All patients received external irradiation with cobalt 60 followed by intracavitary radium application. The median age was 55 years. Squamous cell carcinoma was found in 96.5% of the cases. The 8-year actuarial survival rate was 41%. Bilateral parametrial invasion proved to be a strong prognostic factor. Patients with unilateral disease had a survival rate of 43% whereas in those with bilateral involvement it was only 15% (P less than 0.005). The total pelvic failure rate was 29.5%. The overall incidence of distant metastasis was 11%. The complication rate (minor and major complications) was high, with vaginal stenosis (22.5%), proctitis (21.5%), cystitis (13.5%), and fistulae (4%) occurring in 33, 32, 20, and 6 patients, respectively. New treatment modalities are urgently needed for advanced carcinoma of the cervix. Bilateral parametrial involvement is an unfavorable prognostic factor and this should be kept in mind when designing new protocols.