Colorectal cancer incidence and mortality trends by sex and population group in South Africa: 2002-2014.

BACKGROUND: South Africa (SA) has experienced a rapid transition in the Human Development Index (HDI) over the past decade, which had an effect on the incidence and mortality rates of colorectal cancer (CRC). This study aims to provide CRC incidence and mortality trends by population group and sex in SA from 2002 to 2014. METHODS: Incidence data were extracted from the South African National Cancer Registry and mortality data obtained from Statistics South Africa (STATS SA), for the period 2002 to 2014. Age-standardised incidence rates (ASIR) and age-standardised mortality rates (ASMR) were calculated using the STATS SA mid-year population as the denominator and the Segi world standard population data for standardisation. A Joinpoint regression analysis was computed for the CRC ASIR and ASMR by population group and sex. RESULTS: A total of 33,232 incident CRC cases and 26,836 CRC deaths were reported during the study period. Of the CRC cases reported, 54% were males and 46% were females, and among deaths reported, 47% were males and 53% were females. Overall, there was a 2.5% annual average percentage change (AAPC) increase in ASIR from 2002 to 2014 (95% CI: 0.6-4.5, p-value < 0.001). For ASMR overall, there was 1.3% increase from 2002 to 2014 (95% CI: 0.1-2.6, p-value < 0.001). The ASIR and ASMR among population groups were stable, with the exception of the Black population group. The ASIR increased consistently at 4.3% for black males (95% CI: 1.9-6.7, p-value < 0.001) and 3.4% for black females (95% CI: 1.5-5.3, p-value < 0.001) from 2002 to 2014, respectively. Similarly, ASMR for black males and females increased by 4.2% (95% CI: 2.0-6.5, p-value < 0.001) and 3.4% (, 95%CI: 2.0-4.8, p-value < 0.01) from 2002 to 2014, respectively. CONCLUSIONS: The disparities in the CRC incidence and mortality trends may reflect socioeconomic inequalities across different population groups in SA. The rapid increase in CRC trends among the Black population group is concerning and requires further investigation and increased efforts for cancer prevention, early screening and diagnosis, as well as better access to cancer treatment.

Completeness of Reporting for Breast Cancer Data in the National Pathology-Based Cancer Registry in South Africa.

BACKGROUND: It is important for a cancer registry to have adequate coverage of the catchment area to accurately estimate the cancer burden. This study aimed to determine the pathology-based South African National Cancer Registry's (NCR's) catchment rate of breast cancer cases using a hospital-based cancer registry as reference. METHODS: Using 2 record linkage approaches, a combination of deterministic record linkage (DRL) and probabilistic record linkage (PRL), we linked a breast cancer hospital registry (n = 398) from 2015 with breast cancer registry data from the NCR (n = 16,642). Firstly, using DRL, we matched and linked records using the unique laboratory report number. Records that were not matched using DRL were linked using PRL. Manual reviews of both data sources were then performed to evaluate records that did not match using either DRL or PRL. The NCR's catchment rate was calculated using the total number of matched records from the hospital registry to the NCR breast cancer registry. RESULTS: Of 398 records from the hospital registry, 397 were matched to the NCR breast cancer registry, giving the NCR a catchment rate of 99.75%. A total of 291 records were matched with NCR records by DRL; 95, by PRL; and 11, by manual review. Only 1 record did not match. CONCLUSION: Nearly all hospital breast cancer cases were found in the NCR database. This suggests that the workflow used by the NCR for the identification, collection, and registration of breast cancer cases diagnosed histologically is adequate for this hospital.

Trends in Melanoma Mortality in the Population Groups of South Africa.

The incidence of cutaneous melanoma (CM) is increasing in countries around the world. However, little is known about melanoma trends in African countries by population group. We studied CM mortality in South Africa from 1997 to 2014 to partly address this knowledge gap. Unit record mortality data for all South Africans who died from CM (n = 8,537) were obtained from Statistics South Africa. Join-point regression models were used to assess whether there was a statistically significant change in the direction and/or magnitude of the annual trends in CM mortality. A significant increasing trend of 11% per year was observed in age-adjusted mortality rates in men between 2000 and 2005 (p < 0.01), rising from 2 to 3 per 100,000. There was also a statistically significant increase of 180% per year among White South Africans from 1997 to 1999 (p < 0.05) and of 3% from 1999 to 2014 (p < 0.01). These results may be used to inform CM awareness campaigns and will motivate efforts to improve the collection and analysis of relevant statistics regarding the present burden of CM in South Africa.

Investigation of breast cancer sub-populations in black and white women in South Africa.

PURPOSE: Bimodal age distributions at diagnosis have been widely observed among US and European female breast cancer populations. To determine whether bimodal breast cancer distributions are also present in a sub-Saharan African population, we investigated female breast cancer in South Africa. METHODS: Using the South African National Cancer Registry data, we examined age-at-diagnosis frequency distributions (density plots) for breast cancer overall and by their receptor (oestrogen, progesterone and HER2) determinants among black and white women diagnosed during 2009-2011 in the public healthcare sector. For comparison, we also analysed corresponding 2010-2011 US SEER data. We investigated density plots using flexible mixture models, allowing early/late-onset membership to depend on receptor status. RESULTS: We included 8857 women from South Africa, 7176 (81 %) with known oestrogen receptor status, and 95064 US women. Bimodality was present in all races, with an early-onset mode between ages 40-50 years and a late-onset mode among ages 60-70 years. The early-onset mode was younger in South African black women (age 38), compared to other groups (45-54 years). CONCLUSIONS: Consistent patterns of bimodality and of its receptor determinants were present across breast cancer patient populations in South Africa and the US. Although the clinical spectrum of breast cancer is well acknowledged as heterogeneous, universal early- and late-onset age distributions at diagnosis suggest that breast cancer etiology consists of a mixture two main types.

Hematologic malignancies in South Africa 2000-2006: analysis of data reported to the National Cancer Registry.

Little is known about the incidence patterns of hematologic malignancies in Sub-Saharan Africa, including South Africa. We estimated incidence rates of pathology-confirmed adult cases of leukemia, myeloma and related diseases (myeloma), Hodgkin lymphoma (HL), and non-Hodgkin lymphoma (NHL) reported to the National Cancer Registry of South Africa (NCR) between 2000 and 2006, by age, gender, and population group (Black, White, Coloured, Asian/Indian). Gender-specific age-standardized rates were calculated overall and by population group and incidence rate ratios (IRRs) were estimated using Poisson regression models. Between 2000 and 2006, there were 14662 cases of leukemia, myeloma, HL, and NHL reported to the registry. Incidence rates of reported hematologic malignancies were generally 20-50% higher among males than females. Our analyses suggested marked differences in the rates of reported hematologic malignancies by population group which were most pronounced when comparing the White versus Black population groups (IRRs ranging from 1.6 for myeloma to 3.8 for HL for males and females combined). Challenges related to diagnosis and reporting of cancers may play a role in the patterns observed by population group while the set-up of the NCR (pathology-based) could lead to some degree of under-ascertainment in all groups. This is the first country-wide report of the incidence of hematologic malignancies in South Africa. Despite challenges, it is important to analyze and report available national cancer incidence data to raise awareness of the cancer burden and to characterize patterns by demographic characteristics so as ultimately to improve the provision of cancer-related health care.

Establishment of a cancer surveillance programme: the South African experience.

Cancer is projected to become a leading cause of morbidity and mortality in low-income and middle-income countries in the future. However, cancer incidence in South Africa is largely under-reported because of a lack of nationwide cancer surveillance networks. We describe present cancer surveillance activities in South Africa, and use the International Agency for Research on Cancer framework to propose the development of four population-based cancer registries in South Africa. These registries will represent the ethnic and geographical diversity of the country. We also provide an update on a cancer surveillance pilot programme in the Ekurhuleni Metropolitan District, and the successes and challenges in the implementation of the IARC framework in a local context. We examine the development of a comprehensive cancer surveillance system in a middle-income country, which might serve to assist other countries in establishing population-based cancer registries in a resource-constrained environment.

Childhood cancer incidence patterns by race, sex and age for 2000-2006: a report from the South African National Cancer Registry.

Higher childhood cancer incidence rates are generally reported for high income countries although high quality information on descriptive patterns of childhood cancer incidence for low or middle income countries is limited, particularly in Sub-Saharan Africa. There is a need to quantify global differences by cancer types, and to investigate whether they reflect true incidence differences or can be attributed to under-diagnosis or under-reporting. For the first time, we describe childhood cancer data reported to the pathology report-based National Cancer Registry of South Africa in 2000-2006 and compare our results to incidence data from Germany, a high income country. The overall age-standardized incidence rate (ASR) for South Africa in 2000-2006 was 45.7 per million children. We observed substantial differences by cancer types within South Africa by racial group; ASRs tended to be 3-4-fold higher in South African Whites compared to Blacks. ASRs among both Black and White South Africans were generally lower than those from Germany with the greatest differences observed between the Black population in South Africa and Germany, although there was marked variation between cancer types. Age-specific rates were particularly low comparing South African Whites and Blacks with German infants. Overall, patterns across South African population groups and in comparison to Germans were similar for boys and girls. Genetic and environmental reasons may probably explain rather a small proportion of the observed differences. More research is needed to understand the extent to which under-ascertainment and under-diagnosis of childhood cancers drives differences in observed rates.

Erratum to "prostate cancer in South Africa: pathology based national cancer registry data (1986-2006) and mortality rates (1997-2009)".

[This corrects the article DOI: 10.1155/2014/419801.].

Racial comparison of receptor-defined breast cancer in Southern African women: subtype prevalence and age-incidence analysis of nationwide cancer registry data.

BACKGROUND: Receptor-defined breast cancer proportions vary across Africa. They have important implications for survival prospects and research priorities. METHODS: We studied estrogen receptor (ER), progesterone receptor (PR), and HER2 receptor statuses in two multiracial Southern African countries with routine diagnostic immunohistochemistry. A total of 12,361 women with histologically confirmed breast cancer diagnosed at age ≥20 years during (i) 2009-2011 from South Africa's national cancer registry (public sector) and (ii) 2011-2013 from Namibia's only cancer hospital were included. Crude, age, and age + laboratory-adjusted ORs of receptor status were analyzed using logistic regression, and age-incidence curves were analyzed using Poisson regression. RESULTS: A total of 10,047 (81%) women had known ER status. Ranking of subtypes was consistent across races: ER(+)/PR(+)HER2(-) was most common (race-specific percentage range, 54.6%-64.8%), followed by triple-negative (17.4%-21.9%), ER(+)/PR(+)HER2(+) (9.6%-13.9%), and ER(-)PR(-)HER2(+) (7.8%-10.9%). Percentages in black versus white women were 33.8% [95% confidence (CI), 32.5-35.0] versus 26.0% (24.0-27.9) ER(-); 20.9% (19.7-22.1) versus 17.5% (15.4-19.6) triple-negative; and 10.7% (9.8-11.6) versus 7.8% (6.3-9.3) ER(-)PR(-)HER2(+). Indian/Asian and mixed-ancestry women had intermediate values. Age-incidence curves had similar shapes across races: rates increased by 12.7% per year (12.2-13.1) across ER subtypes under the age of 50 years, and thereafter slowed for ER(+) (1.95%) and plateaued for ER(-) disease (-0.1%). CONCLUSIONS: ER(+) breast cancer dominates in all Southern African races, but black women have a modest excess of aggressive subtypes. IMPACT: On the basis of the predominant receptor-defined breast tumors in Southern Africa, improving survival for the growing breast cancer burden should be achievable through earlier diagnosis and appropriate treatment.

Prostate cancer in South Africa: pathology based national cancer registry data (1986-2006) and mortality rates (1997-2009).

Prostate cancer is one of the most common male cancers globally; however little is known about prostate cancer in Africa. Incidence data for prostate cancer in South Africa (SA) from the pathology based National Cancer Registry (1986-2006) and data on mortality (1997-2009) from Statistics SA were analysed. World standard population denominators were used to calculate age specific incidence and mortality rates (ASIR and ASMR) using the direct method. Prostate cancer was the most common male cancer in all SA population groups (excluding basal cell carcinoma). There are large disparities in the ASIR between black, white, coloured, and Asian/Indian populations: 19, 65, 46, and 19 per 100 000, respectively, and ASMR was 11, 7, 52, and 6 per 100 000, respectively. Prostate cancer was the second leading cause of cancer death, accounting for around 13% of male deaths from a cancer. The average age at diagnosis was 68 years and 74 years at death. For SA the ASIR increased from 16.8 in 1986 to 30.8 in 2006, while the ASMR increased from 12.3 in 1997 to 16.7 in 2009. There has been a steady increase of incidence and mortality from prostate cancer in SA.

The incidence and body site of skin cancers in the population groups of South Africa.

BACKGROUND/PURPOSE: Data regarding basal cell carcinoma (BCC), squamous cell carcinoma of the skin (SSCC) and cutaneous melanoma (CM) in multiracial populations are sparse. Here the incidence and body site of these tumours in the South African population in 2000-2004 were analysed. METHODS: Annual age-standardized incidences and body sites of BCC, SSCC and CM in black, coloured, Asian and white groups were obtained from histological confirmed cases, reported to the National Cancer Registry. RESULTS: Highest annual incidences of BCC, SSCC and CM occurred in the white group, followed by coloured, then Asian and then black. BCCs and SSCCs were about twice as common in males than females. CM was the least frequent skin tumour, and BCC the most frequent, except in black people. The head was the commonest body site for SSCC and BCC in all groups and both sexes, whereas the lower limb was the predominant site for CM in black people. Mean age at diagnosis was generally mid-50s for CM, and mid-60s for BCC and SSCC. CONCLUSIONS: In South Africa, differences in reported incidence rates and body sites of skin tumours by population group and sex occur. Host characteristics, particularly skin phototype, and personal behaviour are likely to affect the risk of these cancers.

Repeatability of Manual Coding Of Cancer Reports in the South African National Cancer Registry; 2010

"Data validity is a very important aspect of cancer registries in ensuring data quality for research and interventions. This study focused on evaluating the repeatability of manual coding of cancer reports in the South African National Cancer Registry (NCR). This cross-sectional study used the Delphi technique to classify 48 generic tumour sites into sites that would be most likely (""difficult"") and least likely (""not difficult"") to give rise to discordant results among coders. Reports received from the Charlotte Maxeke Academic Hospital were manually recoded by five coders (2 301 reports; e.g. approximately 400 reports each) for intracoder agreement; and by four coders (400 reports) for inter-coder agreement. Unweighted kappa statistics were calculated and interpreted using Byrts' criteria. After four rounds of the Delphi technique; consensus was reached on the classification of 91.7 (44/48) of the sites. The remaining four sites were classified according to modal expert opinion. The overall kappa was higher for intra-coder agreement (0.92) than for inter-coder agreement (0.89). ""Not difficult"" tumour sites reflected better agreement than ""difficult"" tumour sites. Ten sites (skin other; basal cell carcinoma of the skin; connective tissue; other specified; lung; colorectal; prostate; oesophagus; naso-oropharynx and primary site unknown) were among the top 80 misclassified sites. The repeatability of manual coding at the NCR was rated as ""good"" according to Byrts' criteria. Misclassified sites should be prioritised for coder training and the strengthening of the quality assurance system."