Abstract
INTRODUCTION:
Cervical cancer is a significant health issue worldwide. It is the fourth most common cancer among women with more than 85% of new cases of the disease occurring in low- and middle-income countries. Cervical cancer is the most common cancer among women in Ghana. Incidence and mortality rates are unknown due to an absence of a national-based population cancer registry. HPV positivity has been shown to be a necessary initiator of cervical cancer but the infection progresses to cancer only in a small number of women. Cofactors associated with the disease progression are not well understood. The study was designed to assess the epidemiology of cervical cancer in Ghana.
AIMS:
• Estimate the regional cervical cancer incidence and mortality using data from two large referral hospitals in Ghana.
• Use results from the above study to estimate national incidence and mortality rates of the disease.
• Estimate the 1, 3 and 5 year disease-specific survival rates of Ghanaian women diagnosed with invasive cervical cancer.
• Determine the HPV DNA prevalence and prevailing HPV types present in Ghanaian women with and without cervical cancer.
• Determine the associations between cofactors and a woman’s risk of developing cervical cancer in Ghana.
METHODS:
Medical records and other hospital data of women diagnosed with cervical cancer from January 2010 to December 2013 were reviewed at Korle-Bu Teaching Hospital, Accra, and Komfo Anokye Teaching Hospital, Kumasi, in Ghana. Telephone interviews were also conducted for patients and relatives to gather further information.
To assess the risk factors for cervical cancer in Ghana, a hospital-based case-control study was undertaken. Women aged 18-95 years with a new diagnosis of invasive cervical cancer that had been histologically confirmed were considered for inclusion as cases. Controls were a random selection from the same hospitals as the cases. A structured questionnaire was administered to the women after which a request for a cervical smear was made for the reporting of cytological abnormalities and laboratory detection of HPV DNA to establish the HPV types present.
RESULTS:
Using the data from review of medical records and telephone interviews, the incidence, mortality and survival rates of women diagnosed with invasive cervical cancer in Ghana were estimated. An increased risk of cervical cancer with age was found. The incidence rate of cervical cancer was highest for women aged 75-79 years and decreased at older ages. Incidence and mortality rates were higher in the Greater Accra and Ashanti regions of Ghana than for other regions. At three years from diagnosis, overall disease-specific survival was 39%. Unsurprisingly, stage at presentation and histological type were strong predictors of cervical cancer survival. Some forms of treatment were also associated with better survival than others.
A total of 206 women with incident cervical cancer and 230 controls were recruited for the case-control study to identify possible risk factors and cofactors for cervical cancer in Ghana. The results of the case-control study confirmed many known established risk factors associated with cervical cancer. These included age, an increased number of pregnancies, higher parity and oral contraceptive use. In addition, use of firewood for cooking, use of homemade sanitary towels and having a polygamous husband was associated with an increased risk of cervical cancer in this study after adjustment for the presence of highest oncogenic HPV types. High prevalence of HPV was detected among women with cervical cancer (80.1%). HPV types 45, 16, 18, 35 and 52 were the most common types detected among cases. Knowledge of HPV and cervical cancer was very low overall among women with and without cervical cancer.
CONCLUSIONS:
In addition to the presence of high-risk oncogenic HPV DNA, parity and oral contraceptive use was associated with an increase risk of cervical cancer in Ghana. The results of the research suggest that the identification of factors associated with the progression of HPV positivity to invasive cervical cancer may help reduce the burden of cervical cancer in Ghana. In addition, the development of a cancer control programme that takes into consideration the social and cultural factors for the prevention, early detection and diagnosis, treatment and palliative aspects of cervical cancer is needed to combat the disease.