Breast Cancer in Nigeria: Is Non‐Adherence to Chemotherapy Schedules a Major Factor in the Reported Poor Treatment Outcome?

To the Editor: Mortality from breast cancer has been declining steadily in many countries. This has been attributed to early detection, accurate diagnosis and prompt treatment (1,2). This is not the case in most developing countries. Breast cancer is now the leading female malignancy in Nigeria and the leading cause of cancer mortality among women seen in many centers across the country (3). The patients are young; they present late and have an overall poor survival. Various reports from Nigeria have shown a high incidence of tumors with unfavorable histopathological and molecular characteristics (4–6). Although a number of studies have attributed the poor treatment outcome to tumor biology, late presentation and poor knowledge of breast cancer (7), to the best of our knowledge, none has examined the phenomenon of non-adherence to therapeutic regimes and its possible effects on treatment outcome. This study examines the reasons for, and the frequency of occurrence of non-adherence to chemotherapeutic regimes among Nigerian women diagnosed with breast cancer. We also suggest ways to address the problem. A retrospective review of the case notes of patients who have been diagnosed with breast cancer and placed on cyclical chemotherapy regimes between January 1996 and December 2005 was carried out. We were specifically interested in the number of treatment cycles missed or delayed. We were also interested in the reasons why they were missed or delayed. The specific drug combinations were not analyzed, but the most commonly used regime in this centre is a course of six cycles of Cyclophosphamide, Methothrexate and 5-Fluorouracil (CMF). Modified radical mastectomy, axillary sampling and simple mastectomy are the commonest surgical procedures for confirmed breast cancer in the centre. A total of 188 cases were reviewed. Their ages ranged between 27 and 81 years with a mean of 49 (SD 10.3) years. One hundred and five (56%) of them were less than 50 years of age, and only 22 (11.7%) were aged above 65 years (elderly). One hundred and sixty-three (86%) of them presented with late stage (stages 3 & 4) disease. A total of 152 patients (80%) reported non-adherence to treatment at one stage or the other. There was no significant association between age or stage at presentation and non-adherence to treatment (v = 4.390, p = 0.624 and v = 5.465, p = 0.141, respectively). The reasons for non-adherence were available in only 110 patients. Among these patients, 21% received less than 75% while 55% received 50% or less of the expected cycles. About 52% of all patients who failed to take five or all of the six cycle of treatment did so because they could not afford the drugs. Paradoxically, 16% of all non-adherences to the regime was due to patients’ feeling well and did not think it important to continue the schedule. This was seen mostly commonly after the third cycle. Most of these patients however, returned and continued the cycle. About 13% of the patients opted out of treatment regime in order to attend faith ⁄ spiritual healing. About 10% experienced severe adverse effects of drug treatment like severe diarrhea, vomiting, and neutropenia. These patients either withdrew themselves from further treatment or their physician officially delayed their treatment. Other reasons for non-adherence to treatment include hospital staff strikes, unavailability of the drugs to buy, patients forgetting treatment cycle and lack of transportation to the treatment centre. These account for about 19% of non-adherence to treatment. Adequate adjuvant chemotherapy unequivocally improves outcome for breast cancer patients (8). This Address correspondence and reprint requests to: Isaac D. Gukas, BM; Bch, FMCS, MRCSEd, PhD, MA (Higher Education Practice), School of Medicine, Health Policy and Practice, Biomedical Research Centre (BMRC), University of East Anglia, Norwich NR4 7TJ, UK, or e-mail: i.gukas@uea. ac.uk.