Adeniyi Adenipekun

Parity and breastfeeding are protective against breast cancer in Nigerian women

As the relation between reproductive factors and breast cancer risk has not been systematically studied in indigenous women of sub-Saharan Africa, we examined this in a case–control study in Nigeria. In-person interviews were conducted using structured questionnaires to collect detailed reproductive history in 819 breast cancer cases and 569 community controls between 1998 and 2006. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI). Compared with women with menarcheal age <17 years, the adjusted OR for women with menarcheal age ⩾17 years was 0.72 (95% CI: 0.54–0.95, P=0.02). Parity was negatively associated with risk (P-trend=0.02) but age at first live birth was not significant (P=0.16). Importantly, breast cancer risk decreased by 7% for every 12 months of breastfeeding (P-trend=0.005). It is worth noting that the distribution of reproductive risk factors changed significantly from early to late birth cohorts in the direction of increasing breast cancer incidence. Our findings also highlight the heterogeneity of breast cancer aetiology across populations, and indicate the need for further studies among indigenous sub-Saharan women.

Waist–hip ratio and breast cancer risk in urbanized Nigerian women

BackgroundThe aim of this study was to examine the relationship between waist–hip ratio and the risk of breast cancer in an urban Nigerian population.MethodsBetween March 1998 and August 2000, we conducted a case–control study of hospital-based breast cancer patients (n = 234) and population-based controls (n = 273) using nurse interviewers in urban Southwestern Nigeria.ResultsMultivariable logistic regression showed a significant association between the highest tertile of waist–hip ratio and the risk of breast cancer (odds ratio= 2.67, 95% confidence interval = 1.05–6.80) among postmenopausal women. No association was found in premenopausal women.ConclusionThe present study, the first in an indigenous African population, supports other studies that have shown a positive association between obesity and breast cancer risk among postmenopausal women.

Obesity and height in urban Nigerian women with breast cancer.

PURPOSE To examine the relationship between obesity, height, and breast cancer in an urban Nigerian population. METHODS Between March 1998 and August 2000, we conducted a case-control study of hospital-based breast cancer patients (n = 234) and population-based controls (n = 273) using nurse interviewers in urban Southwestern Nigeria. RESULTS The study did not find a significant association between obesity (BMI >/= 30) and breast cancer among all women (OR = 1.51, 95% CI = 0.87-2.62) pre- (OR = 1.21, 95% CI = 0.56-2.60) and post-menopausal breast cancer patients (OR = 1.82, 95% CI = 0.78-4.31) in multivariate logistic regression analysis, while increasing height was positively associated with the risk of breast cancer among all women (OR = 1.05, 1.01 - 1.08), pre- (1.06, 1.01-1.10) and post-menopausal women (1.07, 1.01-1.13) for each cm. Age, irregular period, and early age of onset of periods were also found to be significantly associated with breast cancer risk. CONCLUSION This study failed to demonstrate an association between breast cancer risk and obesity while showing that height is positively associated with risk of breast cancer in urbanized Nigerian women.

Complete allelic analysis of BRCA1 and BRCA2 variants in young Nigerian breast cancer patients

Breast cancer is a leading cause of cancer deaths among women, and is expected to claim the lives of nearly 40 000 individuals in the USA each year (American Cancer Society Breast Cancer Facts and Figures 2003–2004 ). Only 5–10% of breast cancers are associated with mutations in the susceptibility genes BRCA1 and BRCA2 . However, in cases associated with strong family history, mutation rates are higher, ranging from 16% to 26% for BRCA1 1–3 and from 7% to 13% for BRCA2 .2,3 However, many breast cancer patients with strong family histories have no obvious mutations in BRCA1 /2. While there is an active search for other breast cancer susceptibility genes, it is possible that the true contributions of BRCA1 and BRCA2 to early onset breast cancer have been underestimated. Indeed, one study has shown that only 63% of breast cancer families linked to BRCA1 are associated with detectable mutations in BRCA1 .4 Several reasons for this discrepancy are possible. For example, mutations in BRCA1 promoter sequences might be undetectable by current detection techniques. Additionally, inherited genomic rearrangements that inactivate BRCA1 and BRCA2 but cannot be detected by conventional polymerase chain reaction (PCR) based assays have been reported.5,6,7,8,9,10 Finally, it is possible that some genetic variants previously dismissed as “unclassified variants” or “polymorphisms” may have hitherto underappreciated effects on protein synthesis or function. Most studies of BRCA1 and BRCA2 associated breast cancers have focused on white populations, yet several observations suggest that there might be a genetic component to breast cancer susceptibility in families of African ancestry.11 Breast cancer is less common in African populations than in other populations but, when it does occur, it is characterised by an early age of onset and a higher mortality.12–14 Additionally, …

Case-Control Study of Body Size and Breast Cancer Risk in Nigerian Women

Previous studies have shown that weight is inversely associated with premenopausal breast cancer and positively associated with postmenopausal disease. Height has been shown to be positively correlated with breast cancer risk, but the association was not conclusive for premenopausal women. These previous studies were conducted primarily in Western countries, where height is not limited by nutritional status during childhood. The authors assessed the association between breast cancer and anthropometric measures in the Nigerian Breast Cancer Study (Ibadan, Nigeria). Between 1998 and 2009, 1,233 invasive breast cancer cases and 1,101 controls were recruited. The multivariate-adjusted odds ratio for the highest quartile group of height relative to the lowest was 2.03 (95% confidence interval (CI): 1.51, 2.72; P-trend < 0.001), with an odds ratio of 1.22 (95% CI: 1.14, 1.32) for each 5-cm increase, with no difference by menopausal status. Comparing women with a body mass index in the lowest quartile group, the adjusted odds ratio for women in the highest quartile category was 0.72 (95% CI: 0.54, 0.94; P-trend = 0.009) for premenopausal and postmenopausal women. Influence of height on breast cancer risk was quite strong in this cohort of indigenous Africans, which suggests that energy intake during childhood may be important in breast cancer development.

Social barriers to diagnosis and treatment of breast cancer in patients presenting at a teaching hospital in Ibadan, Nigeria.

Globally, breast cancer is the most frequent malignancy in women, and stage at diagnosis is a key determinant of outcome. In low- to middle-income countries, including Nigeria, advanced stage diagnosis and delayed treatment represent a significant problem. That social barriers contribute to delay has been noted in previous research; however, few specific factors have been studied. Using semi-structured interviews, this study identifies social barriers to diagnosis and treatment for patients who presented at University College Hospital Ibadan, Nigeria. Transcripts from the interviews were coded and analysed thematically. Thirty-one patients and five physicians were interviewed. The median age of patients was 51 (range: 28 to above 80), 83% were Christian and 17% were Muslim. Preliminary analysis showed that delays in diagnosis reflected a lack of education as well as the utilisation of non-physician medical services such as pharmacists. Delays in treatment were often due to fear of unanticipated surgery and cost. The majority of women did not know the cause of their breast cancer, but some believed it was caused by a spiritual affliction. This study suggests that further education and awareness of breast cancer for both patients and providers is needed in order to increase early stage diagnosis.

High Dose Rate Brachytherapy in the Treatment of Cervical Cancer: Preliminary Experience with Cobalt 60 Radionuclide Source—A Prospective Study

Iridium-192 is widely used for high-dose rate brachytherapy. Co-60 source with similar geometric and dosimetric properties are now available. It has a longer half life but higher energy than Iridium-192. If Co-60 source can produce similar results, it will be more economical for low resource settings. Objective To evaluate the acute gastrointestinal and genitourinary toxicity associated with Co-60 source in the brachytherapy of cervical cancer. Methods Seventy patients with cervical cancer received 45 Gy in 22 fractions of pelvic external beam radiotherapy and 19.5 Gy in 3 fractions of HDR with Co-60 source using tandem and ring applicators with 6 courses of cisplatin 50 mg/m2 and 5 fluorouracil 1000 mg/m2 every 3 weeks Toxicity was scored using NCI-CTC version 4.0. Results The median total BED (Gy10) for tumor was 86.2 (84.4–88.8) while that for rectum (BED Gy3) was 124.4 (120–133). Two patients (3%) had grade 3 gastrointestinal toxicity while all others had ≤grade 2 toxicity and this is comparable with previous results. Conclusion Co-60 as HDR brachytherapy source is tolerable and is economical for low resource settings.

Radiation Nephritis: Anti-inflammatory Effect of Dexamethasone in Adult Wistar Rats (Rattus norvegicus)

Fue estudiado el efecto anti-inflamatorio de la dexametasona en rinones irradiados de 18 ratas Wistar adultas (Rattus norvegicus). Luego de la aclimatizacion, aleatoriamente se dividieron en 3 grupos de 6 animales por grupo. El grupo control recibio una solucion salina normal, sin recibir drogas ni radiacion. El segundo grupo recibio solucion salina normal y radiacion. El tercer grupo recibio tratamiento previo con dexametasona con 1 mg / kg de peso corporal / dia, durante 2 dias, seguido de radiacion. Los animales fueron expuestos a radiacion con una fraccion independiente de 2.5 Gy de rayos gamma por una fuente de Cobalto-60, usando una maquina de teleterapia AECL Theatron 780-C. Despues de la exposicion a las diferentes intervenciones, los animales fueron sacrificados el dia 14 post-irradiacion y los rinones de cada uno de los animales fueron disecados. Los tejidos renales fueron sometidos a procesamiento histologico, y luego se estudiaron utilizando un objetivo ocular milimetrado calibrado a 2mm para el estudio histomorfometrico. Se demostro que todos los animales irradiados sufrieron perdida de peso 14 dias despues de esta (p <0.05), independientemente de los tratamientos adicionales con dexametasona , siendo estadisticamente significativo. La histomorfometria mostro que el ancho maximo de la capsula glomerular fue significativamente mayor en los grupos irradiados que en el control en p <0.05. El diametro maximo del glomerulo fue significativamente mayor en los animales irradiados en comparacion con los animales control p <0.05. Los resultados de este estudio mostraron que la administracion intraperitoneal, de 1 mg / kg de peso corporal / dia durante 2 dias, de dexametasona antes de comenzar el tratamiento con irradiacion, no impide la perdida de peso ni permite aliviar el edema de los nefrones, injuria producto de la radiacion a las Ratas Wistar.

High-dose-rate brachytherapy in the treatment of uterine cervical cancer using cobalt-60 radionuclide source: Three years treatment outcome

Background: The Iridium-192 radionuclide source is commonly used for high-dose-rate brachytherapy of uterine cervical cancer. The cobalt-60 radionuclide source, which is more economical, is now available with dosimetric properties similar to iridium-192. Objective: To evaluate late gastrointestinal and genitourinary complications, and also the survival pattern in cervical cancer patients treated with cobalt-60 high-dose-rate brachytherapy, three years after treatment. Materials and Methods: Seventy patients, who were treated with high-dose-rate brachytherapy using the cobalt-60 radionuclide source were followed up for three years. All the patients received 45 Gy of external beam radiotherapy in 22 daily fractions, with 19.5 Gy from high-dose-rate brachytherapy, in three fractions, over three weeks, using the cobalt-60 radio nuclide source. The patients also received concurrent cisplatin-based chemotherapy. Late complications were assessed every three months, using Radiation Therapy Oncology Group (RTOG) late toxicity criteria. The pattern of disease control was also assessed. Results: Late complications in the bowel were, six (9%) grade 1, four (6%) grade 2, one (1%) grade 3, and one (1%) grade 4. The late complications affecting the bladder were 5 (7%) grade 1 and 1 (1%) grade 4. Twenty-eight patients (40%) were alive without disease, seven (10%) were alive with disease, seven (10%) died of persistent disease, four (6%) died of metastatic disease, while 24 (34%) were lost to follow-up. Conclusion: The late complications were similar to those reported for Iridium-192 as a source of high-dose brachytherapy. Cobalt-60 high-dose-rate brachytherapy is tolerable, effective, and economical for low resource settings.

Effect of Preconception Gamma Irradiation on Morphometric Assessment of Adult Female Mice and Embryo

El objetivo fue estudiar el efecto de la irradiacion gamma antes de la concepcion sobre la morfometria macroscopica de ratones hembra adultos y los embriones de sus crias. Veinte y siete ratones, 18 hembras y 9 machos, divididos en 3 grupos (control, sin irradiacion e irradiado) con 6 hembras y 3 machos cada uno en proporcion 2:1. Una dosis de radiacion gamma de 1 Gy/min fue aplicada a uno de los ratones expuestos por un equipo Cobalt 60, Theratron modelo 780c, Atomic Energy of Canada Limited (AECL) en el departamento de radioterapia del Hospital University College de Ibadan. Todos los animales se aparearon 1 semana despues de la irradiacion. Se confirmaron los tapones vaginales, y las hembras prenadas fueron sacrificadas en el dia 14 de la gestacion por inhalacion de cloroformo. La morfologia general de los ratones hembras y sus camadas fueron evaluadas y analizadas estadisticamente. Un total de 113 embriones se recolectaron en todos los grupos, 54 del grupo control, 50 del grupo no irradiados y 9 del grupo irradiado. Las evaluaciones morfologicas macroscopicas de los fetos fueron estadisticamente significativas (p<0,05) para los 3 grupos de comparacion. Estos hallazgos sugieren que una irradiacion previa a la concepcion afecta a la morfologia de los ratones hembra y su progenie.