The Epidemiology of Breast Cancer in Oman

Abstract

Background Breast cancer is the most common cancer in females around the world. Annually, more than one million women are diagnosed with breast cancer globally. In Oman, breast cancer is also the most common cancer in females and its incidence has been rising over the years. Published studies have shown that many Omani women have late stage breast cancer at presentation. Possible reasons for this have not been explored. Although Oman has in place a mortality registration database, no population-based mortality data from breast cancer are available. Likewise, the only data available about survival rate of people with breast cancer come from a hospital-based study.

Aims The main aims of the research described in this thesis are: 1) To identify the extent of delay in breast cancer diagnosis in Oman. 2) To assess the relationship between delay and socio-demographic characteristics, medical and obstetric history, nature of presenting symptoms and women’s knowledge about breast cancer. 3) To identify reasons for delay in seeking medical help for self-detected breast cancer symptoms in Omani women. 4) To calculate the population-based survival rate from breast cancer in Oman.

Methods Aims 1, 2 and 3 were addressed by a study of 150 patients attending oncology clinics in both the Royal Hospital and Sultan Qaboos University Hospital, who were interviewed using structured questionnaires. Patient delay was defined as a period of three months or more between an individual's first awareness of a sign or a symptom of illness and the initial medical consultation. In order to calculate survival rate, the National Cancer Registry records were to be linked to mortality databases in Oman (Directorate General of Civil Status and to the Parallel Mortality Database).

Results The final analysis of delay included 144 patients with breast cancer. The median time taken by women in this sample between discovering the breast symptoms and seeing a doctor was 14 days. 56.9% of the patients had a medical consultation in less than a month after detecting symptoms, whereas 20.1 % had a consultation within 1 to 2 months. 22.9 % of the patients delayed consultation by ≥ 3 months. Of the socio-demographic characteristics examined in this study, it was observed that older age, low educational level and employment status were associated with patient delay. Practice of breast self-examination and having a history of chronic disease were also predictors of delay. 44% of patients had early stage disease (stage I/stage II) compared to 56% of patients with late stage disease (stage III/stage IV). However, patient delay was not associated with advanced stage cancer in this study. The main reasons given for delay were: failure to recognise the symptoms to be breast cancer, not seeing oneself at risk for breast cancer, fear and embarrassment, use of alternative therapy and family and work commitments. Due to ethical consideration, I was not able obtain data from Omani NCR and therefore the linking to mortality databases was not possible.

Conclusion This study is the first in Oman to investigate the extent of patient delay for women with self-discovered breast symptoms and the factors that influence this delay. The findings of this study indicate the need for public education aimed at raising breast cancer awareness. Further, initiating a screening program in Oman should be considered to help women achieve diagnosis of the disease in its early stages. Population-based cancer research should be encouraged in Oman, and efforts should be taken to improve the quality and completeness of cancer data, which are important in providing on-going monitoring of cancer.