Trends in the Use of Hypofractionation in Treatment of Breast Cancer in Botswana

PURPOSE/OBJECTIVE(S)

Clinical trials have shown that moderate hypofractionation (HF) is clinically effective as adjuvant treatment to breast conserving surgery or following mastectomy with advanced disease. ASTRO issued updated guidelines in 2018, expanding the population eligible to receive HF to all patients, regardless of age and tumor stage. Use of HF can promote efficient resource utilization for over-burdened health care systems; however, global adoption of HF has been previously only reported via ESTRO survey of individual physicians. These data note that HF following lumpectomy is 40% in Africa vs. >90% in North America, with limited data on the uptake of HF within individual African countries. In this study, we characterize temporal trends and clinical, socio-demographic factors associated with the use of HF in breast cancer in Botswana.

MATERIALS/METHODS

We retrospectively analyzed a cohort of breast cancer patients receiving curative intent radiation between 2015 and 2022 at the only radiation clinic in Botswana. We compared patients' characteristics between those who received HF vs. standard fractionation (SF) and report chi-square statistics when appropriate. We fit a multilevel mixed-effects logistic regression model with a random intercept for district while adjusting for fixed effects such as HIV infection status, laterality, hormone receptor status, and marital status.

RESULTS

A total of 234 patients were prescribed curative intent radiation between 2015 and 2022 in Gaborone, Botswana. Median age at diagnosis was 51 years old, and the majority of patients presented with stage III disease (61.9%, 109/234). 26.9% of this population were women living with HIV (WLWH), and 71% lived >100km from the hospital. HF was utilized overall in 59.4% (139/234) of patients. Most common fractionation patterns included: 4005cGy/15fx and 4267cG/16fx. One patient received ultra-HF (2600cGy/5fx). In unadjusted chi-square analysis, a higher proportion of HF was seen in right vs left-sided breast cancer (65.8% vs. 50.9%, p = 0.02), increasing year of diagnosis from 2015 - 2022 (p<0.001), and among patients >/ = 40 years of age vs. those <40 years of age (62.8% vs 42.1%, p = 0.017). Temporal trends show a significant increase in the utilization of HF starting from 23.8% (5/21) in 2015, to 61.5% (32/52) in 2018, and finally 100% (11/11) of cases in 2022. Our regression analysis shows that there is no statistically significant between-district variance or patient-level factors that associate with the uptake of HF. The overall utilization rate for HF between 2015-2022 was 59.4% (95% CI: 53.0%-65.5%).

CONCLUSION

Based on recent survey results the uptake of HF among African countries is lower than that of North America. To our knowledge, this is the first quantitative analysis of the utilization of HF over 5 years in an African country. Further analysis on factors related to physician prescription of hypofractionation is warranted, including influence of breast laterality, age, and primary surgery type.

SCCAg as a Biomarker of Advanced Stage and OS in Limited Resource Setting for Cervical Cancer

PURPOSE/OBJECTIVE(S)

Elevated serum squamous cell antigen (SCCAg) has been previously correlated with poor survival, extensive tumor involvement, and recurrence for cervical cancer. Failure of serum SCCAg to normalize after treatment completion has also been studied as a poor prognostic indicator. This is the first study describing the association of SCCAg with stage and outcomes in patients diagnosed with cervical cancer in Botswana, in a population with a majority of women who are living with HIV (WLWH).

MATERIALS/METHODS

Patients with histologically confirmed cervical cancer were enrolled in a prospective observational study between August 2016 and April 2020 in Botswana. Among all patients undergoing definitive chemoradiation, serum SCCAg was determined at pre-treatment baseline, end of treatment (EOT), and 3-month follow-up (normal reference range 0.3 -1.9 ng/ml). Normalization of SCCAg was defined as return to the reference range after treatment (SCCAg response), and was measured first at EOT; if EOT values were not available, 3-month values were utilized. Patients were staged according to FIGO 2009 criteria, early stage was defined as Stage I-II; while advanced stage was defined as Stage III-IV. Median follow-up was 44 months. A significant cut-off point for baseline and SCCAg response correlated with overall survival (OS) was calculated utilizing a log-rank test RESULTS: Among 234 patients who were diagnosed with histologically confirmed cervical cancer, 73.5% were WLWH (mean CD4 count 466 cells/mL). 92.9% of all cancers were squamous cell carcinoma. 68.8% of patients had elevated SCCAg at time of diagnosis. There was no significant difference in mean baseline SCCAg between WLWH (13.3 ng/mL) and women living without HIV (9.07 ng/mL), p = 0.1052. There was a significant difference seen in mean SCCAg between early (7.9 ng/mL ± SD 13.4) and advanced (18.9 ng/mL, ± SD 29.8) stage disease at diagnosis, p < 0.0001. Baseline SCCAg > 7.9 ng/mL was found to be associated with worse OS (p < 0.001). 5-year OS was significantly different among patients with SCCAg response < = 2.8 (5-year OS 66.2%), vs. SCCAg >2.8 ng/mL (5-year OS 42.4%). There was no significant difference in average SCCAg values between EOT (p = 0.68) and 3-month follow-up (p = 0.24). There was no difference in the proportion of patients who experienced normalized SCCAg by HIV status (p = 0.67).

CONCLUSION

There was no significant difference in SCCAg among WLWH and women living without HIV. Among patients with elevated SCCAg above normal at baseline, SCCAg was associated with early vs. advanced stage disease. Additionally, there was a significant difference seen in overall survival by two measurement points: baseline SCCAg >7.9 ng/mL and response SCCAg >2.8 ng/mL. SCCAg may be utilized as a biomarker in low-resource settings to refine prognosis. Further studies will be needed to determine utility and validation in predicting recurrence risk and/or lymph node metastases.

Human papillomavirus prevalence among unvaccinated young female college students in Botswana: A cross-sectional study

BACKGROUND

Human papillomavirus (HPV) is a sexually transmitted infection and a causative agent of cervical cancer. It is common in adolescent girls and young women, and the majority of infections are transient and asymptomatic. In Botswana, there are currently no data on the HPV prevalence against which the impact of prophylactic HPV vaccines can be measured.

OBJECTIVES

To establish a baseline HPV prevalence in an unvaccinated cohort of young women.

METHODS

Women aged ≥18 years were recruited from the University of Botswana between September 2016 and May 2020. Demographic and behavioural characteristics of participants were collected. Subsequently, cervicovaginal swabs were obtained and tested for HPV using polymerase chain reaction-restriction fragment length polymorphism. We determined the prevalent HPV types, and evaluated the risk factors associated with HPV positivity.

RESULTS

A total of 978 young women were recruited. Overall, there were 589 (60.2%) participants with HPV infection and 12 (1.2%) with HIV. The median (interquartile range) age of the study participants was 19 (18 - 20) years. Multivariate logistic regression analysis showed that significant factors associated with HPV positivity were sexual activity (adjusted odds ratio (aOR) 2.06; 95% confidence interval (CI) 1.49 - 2.63; p&lt;0.001), number of sex partners ≥3 (aOR 2.10; 95% CI 1.39 - 3.18; p&lt;0.001), and smoking (aOR 2.00; 95% CI 1.26 - 3.20; p=0.004).

CONCLUSION

Our results demonstrate for the first time the prevalence of HPV in unvaccinated young women in Botswana. We found a high prevalence of HPV infection, with statistical differences with different risk factors. This finding supports the need for HPV vaccination strategies for females prior to sexual debut to reduce the future burden of cervical cancer in Botswana.

Persistence and clearance of high-risk human papillomavirus and cervical dysplasia at 1 year in women living with human immunodeficiency virus: a prospective cohort study

OBJECTIVE

Evaluate 1-year outcomes of cervical cancer screening and treatment using primary high-risk human papillomavirus (HPV) testing in women living with human immunodeficiency virus (HIV).

DESIGN

Prospective cohort study.

SETTING

HIV treatment centre in Botswana.

POPULATION

Women living with HIV.

METHODS

Participants underwent cervical cancer screening with high-risk HPV testing and triage evaluation at baseline and 1-year follow up. Excisional treatment was offered as indicated. Histopathology was the reference standard.

MAIN OUTCOME MEASURES

Persistence, clearance and incidence of high-risk HPV infection; and persistence, progression, regression, cure and incidence of cervical dysplasia.

RESULTS

Among 300 women screened at baseline, 237 attended follow up (79%). High-risk HPV positivity significantly decreased from 28% at baseline to 20% at 1 year (P = 0.02). High-risk HPV persistence was 46% and clearance was 54%; incidence was high at 9%. Prevalence of cervical intraepithelial neoplasia Grade 2 (CIN2) or higher was most common in participants with incident high-risk HPV (53%). CIN2 or higher was also common in those with persistent high-risk HPV (32%) and even in those who cleared high-risk HPV (30%). Of the high-risk HPV-positive participants at baseline with <CIN2, 40% progressed to CIN2 or higher at follow up.

CONCLUSION

The high incidence of high-risk HPV and high-grade cervical dysplasia in women living with HIV after one round of high-risk HPV-based screening and treatment raises concern about the rate of progression of high-risk HPV infection to dysplasia. Persistent disease is common. Caution in spacing cervical cancer screening intervals using high-risk HPV testing in women living with HIV is warranted.

TWEETABLE ABSTRACT

High incidence and persistence of HPV and CIN2+ in women living with HIV 1 year after screening and treatment.

Development and launch of the first obstetrics and gynaecology master of medicine residency training programme in Botswana

BACKGROUND

Sub-Saharan Africa (SSA) faces a severe shortage of Obstetrician Gynaecologists (OBGYNs). While the Lancet Commission for Global Surgery recommends 20 OBGYNs per 100,000 population, Botswana has only 40 OBGYNs for a population of 2.3 million. We describe the development of the first OBGYN Master of Medicine (MMed) training programme in Botswana to address this human resource shortage.

METHODS

We developed a 4-year OBGYN MMed programme at the University of Botswana (UB) using the Kern's approach. In-line with UB MMed standards, the programme includes clinical apprenticeship training complemented by didactic and research requirements. We benchmarked curriculum content, learning outcomes, competencies, assessment strategies and research requirements with regional and international programmes. We engaged relevant local stakeholders and developed international collaborations to support in-country subspecialty training.

RESULTS

The OBGYN MMed curriculum was completed and approved by all relevant UB bodies within ten months during which time additional staff were recruited and programme financing was assured. The programme was advertised immediately; 26 candidates applied for four positions, and all selected candidates accepted. The programme was launched in January 2020 with government salary support of all residents. The clinical rotations and curricular development have been rolled out successfully. The first round of continuous assessment of residents was performed and internal programme evaluation was conducted. The national accreditation process was initiated.

CONCLUSION

Training OBGYNs in-country has many benefits to health systems in SSA. Curricula can be adjusted to local resource context yet achieve international standards through thoughtful design and purposeful collaborations.