The spectrum of TP53 mutations in Rwandan patients with gastric cancer

BACKGROUND

Gastric cancer is the sixth most frequently diagnosed cancer and third in causing cancer-related death globally. The most frequently mutated gene in human cancers is TP53, which plays a pivotal role in cancer initiation and progression. In Africa, particularly in Rwanda, data on TP53 mutations are lacking. Therefore, this study intended to obtain TP53 mutation status in Rwandan patients with gastric cancer.

RESULTS

Formalin-fixed paraffin-embedded tissue blocks of 95 Rwandan patients with histopathologically proven gastric carcinoma were obtained from the University Teaching Hospital of Kigali. After DNA extraction, all coding regions of the TP53 gene and the exon-intron boundary region of TP53 were sequenced using the Sanger sequencing. Mutated TP53 were observed in 24 (25.3%) of the 95 cases, and a total of 29 mutations were identified. These TP53 mutations were distributed between exon 4 and 8 and most of them were missense mutations (19/29; 65.5%). Immunohistochemical analysis for TP53 revealed that most of the TP53 missense mutations were associated with TP53 protein accumulation. Among the 29 mutations, one was novel (c.459_477delCGGCACCCGCGTCCGCGCC). This 19-bp deletion mutation in exon 5 caused the production of truncated TP53 protein (p.G154Wfs*10). Regarding the spectrum of TP53 mutations, G:C > A:T at CpG sites was the most prevalent (10/29; 34.5%) and G:C > T:A was the second most prevalent (7/29; 24.1%). Interestingly, when the mutation spectrum of TP53 was compared to three previous TP53 mutational studies on non-Rwandan patients with gastric cancer, G:C > T:A mutations were significantly more frequent in this study than in our previous study (p = 0.013), the TCGA database (p = 0.017), and a previous study on patients from Hong Kong (p = 0.006). Even after correcting for false discovery, statistical significance was observed.

CONCLUSIONS

Our results suggested that TP53 G:C > T:A transversion mutation in Rwandan patients with gastric cancer is more frequent than in non-Rwandan patients with gastric cancer, indicating at an alternative etiological and carcinogenic progression of gastric cancer in Rwanda.

Clinicopathological Characteristics and Mutational Landscape of APC, HOXB13, and KRAS among Rwandan Patients with Colorectal Cancer

Cancer research in Rwanda is estimated to be less than 1% of the total African cancer research output with limited research on colorectal cancer (CRC). Rwandan patients with CRC are young, with more females being affected than males, and most patients present with advanced disease. Considering the paucity of oncological genetic studies in this population, we investigated the mutational status of CRC tissues, focusing on the Adenomatous polyposis coli (APC), Kirsten rat sarcoma (KRAS), and Homeobox B13 (HOXB13) genes. Our aim was to determine whether there were any differences between Rwandan patients and other populations. To do so, we performed Sanger sequencing of the DNA extracted from formalin-fixed paraffin-embedded adenocarcinoma samples from 54 patients (mean age: 60 years). Most tumors were located in the rectum (83.3%), and 92.6% of the tumors were low-grade. Most patients (70.4%) reported never smoking, and 61.1% of patients had consumed alcohol. We identified 27 variants of APC, including 3 novel mutations (c.4310_4319delAAACACCTCC, c.4463_4470delinsA, and c.4506_4507delT). All three novel mutations are classified as deleterious by MutationTaster2021. We found four synonymous variants (c.330C>A, c.366C>T, c.513T>C, and c.735G>A) of HOXB13. For KRAS, we found six variants (Asp173, Gly13Asp, Gly12Ala, Gly12Asp, Gly12Val, and Gln61His), the last four of which are pathogenic. In conclusion, here we contribute new genetic variation data and provide clinicopathological information pertinent to CRC in Rwanda.

Abstract 2609: Non-CpG sites preference in G:C>A:T transition of TP53 in gastric cancer of Eastern Europe (Poland, Romania and Hungary) compared to East Asian countries (China and Japan) : gastric cancer in the world, mutation spectrum revisited

Aim: Mutation spectrum of TP53 in gastric cancer (GC) has been investigated world-widely, but a comparison of mutation spectrum among GCs from various regions in the world are still sparsely documented. In order to identify the difference of TP53 mutation spectrum in GCs in Eastern Europe and in East Asia, we sequenced TP53 in GCs from Eastern Europe, Lujiang (China), and Yokohama, Kanagawa (Japan) and identified the feature of TP53 mutations of GC in these regions.

Subjects and Method: In total, 689 tissue samples of GC were analyzed: 288 samples from East European populations (25 from Hungary, 71 from Poland and 192 from Romania), 268 from Yokohama, Kanagawa, Japan and 133 from Lujiang, Anhui province, China. DNA was extracted from FFPE tissue of Chinese, East European cases; and from frozen tissue of Japanese GCs. PCR products were direct-sequenced by Sanger method, and in ambiguous cases, PCR product was cloned and up to 8 clones were sequenced. We used No. NC_000017.11(hg38) as the reference sequence of TP53. Mutation patterns were categorized into nine groups: six base substitutions, insertion, deletion and deletion-insertion. Within G:C>A:T mutations the mutations in CpG and non-CpG sites were divided. Furthermore, 40 cases of Rwanda GC were compared in the world for mutation spectrum. The Cancer Genome Atlas data (TCGA, ver.R20, July, 2019) having somatic mutation list of GCs from Whites, Asians, and other ethnicities were used as a reference for our data.

Results: The most frequent base substitutions were G:C>A:T transition in all the areas investigated. The G:C>A:T transition in non-CpG sites were prominent in East European GCs, compared with Asian ones. Mutation pattern from TCGA data revealed the same trend between GCs from White (TCGA category) vs Asian countries. Chinese and Japanese GCs showed higher ratio of G:C>A:T transition in CpG sites and A:T>G:C mutation was more prevalent in Asian countries.

Conclusion: The divergence in mutation spectrum of GC in different areas in the world may reflect various pathogeneses and etiologies of GC, region to region. Diversified mutation spectrum in GC in Eastern Europe may suggest GC in Europe has different carcinogenic pathway of those from Asia. Whether the Rwanda pattern belong to Asian or East European would be interesting.

Citation Format: Hiroko Natsume, Kinga Szczepaniak, Hidetaka Yamada, Yuji Iwashita, Marta Gędek, Jelena Šuto, Rika Kasajima, Felix Manirakiza, Augustin Nzitakera, Rei Ishikawa, Eric Rutaganda, François Ngabonziza, Benoit Seminega, Placide Kamali, Vincent Dusabejambo, Belson Rugwizangoga, Nobuhito Nobuhito, Yaping Wang, Yohei Miyagi, Simona Gurzu, Haruhiko Sugimura. Non-CpG sites preference in G:C>A:T transition of TP53 in gastric cancer of Eastern Europe (Poland, Romania and Hungary) compared to East Asian countries (China and Japan) : gastric cancer in the world, mutation spectrum revisited [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2609.

`Teaching Infectious Disease Pathology and Taking it To Africa

With the advent of increasing emerging infectious diseases, rising antibiotic resistance, and the growing number of immunocompromised patients, there is increasing demand for infectious disease (ID) pathology expertise and microbiology testing. At present, infectious disease pathology training and emerging molecular microbiology techniques (e.g. metagenomic next-generation sequencing and whole genome sequencing) are not included in most American Council of Graduate Medical Education (ACGME) medical microbiology fellowship curricula, and, not surprisingly, many institutions lack anatomic pathologists with expertise in ID pathology and advanced molecular diagnostics. In this article, we describe the curriculum and structure of the Franz von Lichtenberg Fellowship in Infectious Disease and Molecular Microbiology at Brigham and Women's Hospital in Boston, MA. We emphasize the value of a training model that strives to integrate anatomic pathology, clinical pathology, and molecular pathology by providing examples in a case-based format and presenting selected metrics of the potential impact of such integrative infectious disease pathology service, and briefly describing opportunities and challenges of our global health efforts in Rwanda.

The use of Vsee videoconferencing for live telepathology in Rwanda, a potential solution for resource-limited area

Objective

The shortage of pathologists is a worldwide problem that is more severe in Africa. One of the solutions is the use of telepathology (TP); however, most of the TP systems are expensive and unaffordable in many developing countries. At the University Teaching Hospital of Kigali, Rwanda, we assessed the possibility of combining commonly available laboratory tools into a system that can be used for diagnostic TP using Vsee videoconferencing.

Methodology

Using an Olympus microscope (with a camera) operated by a laboratory technologist, histologic images were transmitted to a computer whose screen was shared, using Vsee, with a remotely located pathologist who made the diagnoses. Sixty consecutive small biopsies (≤6 glass slides) from different tissues were examined to make a diagnosis using live Vsee-based videoconferencing TP. Vsee-based diagnoses were compared to pre-existing light microscopy-based diagnoses. Percent agreement and unweighted Cohen's kappa coefficient of the agreement were calculated.

Results

For agreement between conventional microscopy-based and Vsee-based diagnoses, we found an unweighted Cohen's kappa of 0.77 ± 0.07SE with a 95% CI of 0.62-0.91. The perfect percent agreement was 76.6% (46 of 60). Agreement with minor discrepancy was 15% (9 of 60). There were 2 cases of major discrepancy (3.30%). We were unable to make a diagnosis in 3 cases (5%) because of poor image quality related to the instantaneous internet connectivity problems.

Conclusion

This system provided promising results. However, additional studies to assess other parameters which can affect its performance are needed before this system can be considered an alternative method of providing TP services in resource-limited settings.

Predictors of molecular subtypes in women with breast cancer in Rwanda

INTRODUCTION: Breast cancer (BC) constitutes a major public health problem worldwide. It remains a major scientific, clinical and societal challenge, generally in Africa and particularly in Rwanda. The purpose of this study was to determine clinical and histopathological predictors of BC molecular subtypes in Rwandan women.METHODS: A retrospective cohort study including patients with histological confirmation of BC. Using R statistical software, a regression model for multinomial responses was developed. Univariate and multivariate logistic regression analyses were used to identify independent BC molecular subtypes predictors. A two-sided p<0.05 indicated a statistically significant difference.RESULTS: Forty seven percent of cases presented with advanced stages (Stage III and IV). Postmenopausal BC (p=0.0142), absence of infertility (p=0.018) predicted Luminal A subtype with a predictive accuracy of 0.65. Age (p=0.003), postmenopausal BC (p=0.005), absence of axillar lymph nodes (p= 0.008) and poorly differentiated tumor (p=0.012) were predictors for Luminal B subtype with a predictive accuracy of 0.86. Age (p=0.045), BMI (p=0.005), rapid progression (p=0.032), tumor size T2-T3 (p<0.001) were predictors of HER2-Enriched subtype with a predictive accuracy of 0.70. Age below 40 (p=0.005), painless mass (p=0.030), nodal involvement (p=0.008), Nottingham grade 3 (p<0.001) predicted Triple Negative tumors with a predictive accuracy of 0.71.CONCLUSION: Clinical and histopathological tumor characteristics can be used to predict BC molecular subtypes with acceptable accuracy. Further studies are needed to explore the possibility of developing a scoring system for clinical decision-making, especially in settings where immunohistochemistry testing is limited.

Knowledge, Barriers and Motivators to Cervical Cancer Screening in Rwanda: A Qualitative Study

Background

Cervical cancer is a global public health problem with marked geographical disparity. High morbidity and mortality rates in developing countries are associated with low screening rates. In 2020, in Rwanda, 3.7 million women aged 15–59 years were at risk of developing cervical cancer, the most commonly diagnosed female cancer in Rwanda. Despite Rwanda being the first African country to vaccinate against human papilloma virus with a three-dose regimen vaccination coverage of nearly 93% in the target population of girls aged <15 years, and having established cervical cancer screening program, recent studies have found low screening rates. Our study sought to determine knowledge, motivators and barriers of cervical cancer screening.

Methods

We conducted a qualitative descriptive study; using focus group interview in an urban health facility (Muhima district hospital) and a rural health center (Nyagasambu health center) offering cervical screening services in Rwanda. Participants were women seeking these services and other women attending the health facility for any reason, and female staff working in these facilities. Interviews were recorded and transcribed, and data were analyzed using content analysis.

Results

Thirty women participated in focus group interview, with an average age of 39 years. Many of women showed knowledge about cervical cancer existence and prevention methods. However, fear for pain, lack of knowledge about screening, how and where the screening was done, and concern for privacy were recurring subthemes. Some participants also mentioned lack of health insurance as a barrier for cervical cancer screening.

Conclusion

Barriers to uptake cervical cancer screening services in Rwanda are related to poor information about cervical cancer and the importance of screening as well as non-adherence to medical insurance. Population sensitization through campaign and community outreach activities could have a positive impact on increasing the usage of cervical cancer screening in Rwanda.

Experience and Perception of Patients and Healthcare Professionals on Acute Leukemia in Rwanda: A Qualitative Study

Purpose

To explore challenges associated with the timely diagnosis, therapy, and prognosis of acute leukemia in Rwanda.

Methods

This is a qualitative study using a phenomenological approach that involved patients, patients’ guardians, and healthcare professionals such as physicians from district hospitals and specialists from referral hospitals, as well as healthcare administrators. The primary data were collected from district and referral hospitals and central healthcare administration in Rwanda. The data were collected between July and October 2019. In-depth interviews were conducted, and thematic analysis was employed to interpret the results.

Results

We identified barriers to seeking healthcare such as (i) insufficient knowledge within the population may lead patients and their guardians to consult traditional healers before seeking qualified medical care, and (ii) financial constraints that preclude payment of healthcare fees or other out-of-pocket cost related to diagnosis and treatment. We also observed that the referral system is tedious and primary healthcare facilities lack the competence and resources for the necessary diagnostic practices. Both may further delay diagnosis and therapy. Accordingly, healthcare professionals at the referral hospitals stated that most patients were seen at an advanced stage of the disease. For the treatment of acute lymphoblastic leukemia (ALL), only chemotherapy is utilized in Rwanda, while bone marrow (BM) transplantation is not available. Palliation is the only available treatment for the vast majority of Rwandan acute myeloid leukemia (AML) patients.

Conclusion

ALL and AML are likely under-reported in Rwanda and diagnosis may be delayed, which may be explained by patient-related factors (lack of knowledge, financial constraints), a tedious referral system, and suboptimal diagnostic resources.

Pathology Characteristics of Lymphomas in Rwanda: A Retrospective Study

Background:

Lymphomas have been a global challenge for many decades and despite measures for prevention and management, the incidence continues to increase. There are two main categories, which are Non-Hodgkin's Lymphomas and Hodgkin's Lymphomas and most common etiologies are environmental, genetic alteration, radiation and some viruses.

Objective:

To describe pathology characteristics of lymphomas in Rwanda based on Hematoxylin and Eosin stained glass slides and immuno histo chemistry, and classify them according to clinical aggressiveness.

Patients and Methods:

We conducted a retrospective observational and descriptive study from January 2013 to December 2019. Lymphoma cases were retrieved together with relevant clinical and pathological information, and reviewed by independent pathologists. Histological diagnosis was classified according to the 2008 World Health Organization system in order to assign clinical aggressiveness of the lymphoma.

Results:

Three hundred and six lymphoma cases were enrolled. Males contributed to 57% of all reviewed case, and slightly over 50% were young aged ≤35 years. Approximately 191 (62%) of cases were nodal lymphomas. Approximately one fifth (18%) of lymphoma cases were HIV positive. Most 213(70%) cases were Non-Hodgkin's Lymphomas of aggressive forms 164(77%). Among 164 cases of aggressive Non-Hodgkin's Lymphomas, diffuse large B cell lymphoma was the leading subtype 91(55.5%), followed by solid lymphoblastic lymphoma 32(19.5%) and Burkitt lymphoma 17(10.4%). Among all Hodgkin lymphoma cases, 90(97%) were classical Hodgkin lymphomaof nodular sclerosis subtype. Hodgkin lymphoma patients were younger compared to Non-Hodgkin's Lymphomas patients (mean age of 24.78±16.3 years versus 38.6±22. 5years, p=.000).

Conclusion:

Substantial proportion of Lymphomapatients in Rwanda were also HIV positive. Interestingly, Non-Hodgkin's Lymphomas in Rwanda are predominated by the most aggressive forms, and these mostly affect a younger population. Optimal characterisation of such cases, using advanced methods, is recommended.

Occurrence of Helicobacter Pylori in Specimens of Chronic Gastritis and Gastric Adenocarcinoma Patients: A Retrospective Study at University Teaching Hospital, Kigali, Rwanda

Introduction:

Helicobacter pylori (H. pylori) infection is the major cause of gastroduodenal diseases in populations of different ages. We conducted aretrospective studyusing archived tissue samples to determine the prevalence of H. pylori infection among patients diagnosed with gastritis and gastric adenocarcinoma by histopathology cases in one hospital in Rwanda.

Materials and methods:

Cases of chronic gastritis and gastric adenocarcinoma histologically diagnosed in a tertiary hospital in Rwanda over the period of 2016-2018 were studied for the presence of H. pylori using immunohistochemistry. Diagnosis of positive cases considered immunoreactivity as well as bacterial morphology, including spiral, rod-shaped, angulated and coccoid forms.

Results:

Three hundred and seven cases were included in this study; chronic gastritis and gastric adenocarcinoma representing 39% and 61%, respectively. The overall frequency of H. pylori infection was 77.5% (80% among chronic gastritis cases versus 76% among gastric adenocarcinoma cases). Prevalence of H. pylori infection in chronic gastritis and adenocarcinoma did not significantly associate with age and sex.

Conclusion:

The prevalence of H. pylori was high among chronic gastritis and gastric adenocarcinoma cases in Rwanda. Pathologists should investigate the presence of H. pylori in gastric biopsies. Our data shows immunohistochemistry method is feasible and adequate to facilitate detection of H. pylori, which may guide timely treatment.

Building Capacity and Infrastructure at Hospitals Implementing Minimally Invasive Tissue Sampling: Experience and Lessons Learned From Nepal, Rwanda, and Tanzania

BACKGROUND

Minimally invasive tissue sampling (MITS) is a useful tool to determine cause of death in low- and middle-income countries (LMICs). In 2019 the MITS Surveillance Alliance supported the implementation of small-scale postmortem studies using MITS in several LMICs.

METHODS

In this article we describe the preparations, challenges, and lessons learned as part of implementing MITS across 4 study sites in 3 countries: Nepal, Rwanda, and Tanzania. We describe the process for building capacity to conduct MITS, which consisted of training in MITS sample collection, individual site assessment to determine readiness and gaps prior to implementation, site visits as sites began implementation of MITS, and feedback based on remote evaluation of histology slides via an online portal.

RESULTS

The 4 study sites each conducted 100 MITS, for a total of 400. All 4 sites lacked sufficient infrastructure and facilities to conduct MITS, and upgrades were required. Common challenges faced by sites included that clinical autopsies were neither routinely conducted nor widely accepted. Limited clinical records made cause of death determination more difficult. Lessons learned included the importance of sensitization of the community and medical staff to MITS to enhance understanding and increase consent.

CONCLUSIONS

The study sites accomplished MITS and utilized the available support systems to overcome the challenges. The quality of the procedures was satisfactory and was facilitated through the organized capacity-building programs.

Exploring Perceptions and Acceptance of Minimally Invasive Tissue Sampling among Bereaved Relatives and Health-Care Professionals in Rwanda

Purpose

In most low- and lower middle-income countries (LMICs), minimally invasive tissue sampling (MITS) is a relatively new procedure for identifying the cause of death (CoD). This study aimed to explore perceptions and acceptance of bereaved families and health-care professionals regarding MITS in the context of MITS initiation in Rwanda as an alternative to clinical autopsy.

Methods

This was a qualitative phenomenological study with thematic analysis. Participants were bereaved relatives (individual interviews) and health-care professionals (focus-group discussions) involved in MITS implementation. It was conducted in the largest referral and teaching hospital in Rwanda.

Results

Motivators of MITS acceptance included eagerness to know the CoD, noninvasiveness of MITS, trust in medics, and the fact that it was free. Barriers to consent to MITS included inadequate explanations from health-care professionals, high socioeconomic status, lack of power to make decisions, and lack of trust in medics. Health-care professionals perceived both conventional autopsy and MITS as gold-standard procedures in CoD determination. They recommended including MITS among hospital services and commended the post-MITS multidisciplinary discussion panel in CoD determination. They pointed out that there might be reticence in approaching bereaved relatives to obtain consent for MITS. Both groups of participants highlighted the issue of delay in releasing MITS results.

Conclusion

Both health-care professionals and bereaved relatives appreciate that MITS is an acceptable procedure to include in routine hospital services. Dealing with barriers met by either group is to be considered in the eventual next phases of MITS implementation in Rwanda and similar sociocultural contexts.

Use of the Xpert Breast Cancer STRAT4 for Biomarker Evaluation in Tissue Processed in a Developing Country

Objectives

Breast cancer immunohistochemistry (IHC) biomarker testing is limited in low-resource settings, and an alternative solution is needed. A point-of-care mRNA STRAT4 breast cancer assay for ESR1, PGR, ERBB2, and MKi67, for use on the GeneXpert platform, has been recently validated on tissues from internationally accredited laboratories, showing excellent concordance with IHC.

Methods

We evaluated STRAT4/IHC ESR1/estrogen receptor (ER), ERBB2/human epidermal growth factor receptor 2 (HER2) concordance rates of 150 breast cancer tissues processed in Rwanda, with undocumented cold ischemic and fixation time.

Results

Assay fail/indeterminate rate was 2.6% for ESR1 and ERBB2. STRAT4 agreement with ER IHC was 92.5% to 93.3% and 97.8% for HER2, for standard (1x) and concentrated (4x) reagent-conserving protocols, respectively. Eleven of 12 discordant ER/ESR1 cases were ESR1- negative/IHC-positive. These had low expression of ER by IHC in mostly very small tumor areas tested (7/12; <25 mm²). In two of three discordant HER2 cases, the STRAT4-ERBB2 result correlated with the subsequent fluorescence in situ hybridization (FISH) result. STRAT4-ERBB2 results in 9 of 10 HER2-IHC equivocal cases were concordant with FISH.

Conclusions

The STRAT4 assay is an alternative for providing quality-controlled breast cancer biomarker data in laboratories unable to provide quality and/or cost-efficient IHC services.

State of Cancer Control in Rwanda: Past, Present, and Future Opportunities

Rwanda is a densely populated low-income country in East Africa. Previously considered a failed state after the genocide against the Tutsi in 1994, Rwanda has seen remarkable growth over the past 2 decades. Health care in Rwanda is predominantly delivered through public hospitals and is emerging in the private sector. More than 80% of patients are covered by community-based health insurance (Mutuelle de Santé). The cancer unit at the Rwanda Biomedical Center (a branch of the Ministry of Health) is responsible for setting and implementing cancer care policy. Rwanda has made progress with human papillomavirus (HPV) and hepatitis B vaccination. Recently, the cancer unit at the Rwanda Biomedical Center launched the country’s 5-year National Cancer Control Plan. Over the past decade, patients with cancer have been able to receive chemotherapy at Butaro Cancer Center, and recently, the Rwanda Cancer Center was launched with 2 linear accelerator radiotherapy machines, which greatly reduced the number of referrals for treatment abroad. Palliative care services are increasing in Rwanda. A cancer registry has now been strengthened, and more clinicians are becoming active in cancer research. Despite these advances, there is still substantial work to be done and there are many outstanding challenges, including the need to build capacity in cancer awareness among the general population (and shift toward earlier diagnosis), cancer care workforce (more in-country training programs are needed), and research.

Human papillomavirus genotypes in cervical and other HPV-related anogenital cancer in Rwanda, according to HIV status

The study aim was to describe human papillomavirus (HPV)-attributable cancer burden in Rwanda, according to anogenital cancer site, HPV type, age and HIV status. Tissue specimens of cervical, vulvar, vaginal, penile and anal cancer diagnosed in 2012-2018 were retrieved from three cancer referral hospitals and tested for high-risk (HR) HPV DNA. Cervical cancer represented the majority of cases (598 of 738), of which 96.0% were HR-HPV positive. HPV-attributable fractions in other cancer sites varied from 53.1% in 81 penile, through 76.7% in 30 vulvar, 83.3% in 24 vaginal, up to 100% in 5 anal cases. HPV16 was the predominant HR-HPV type in cervical cancer (55.0%), followed by HPV18 (16.6%) and HPV45 (13.4%). HPV16 also predominated in other cancer sites (60-80% of HR-HPV-attributable fraction). For cervical cancer, type-specific prevalence varied significantly by histology (higher alpha-9 type prevalence in 509 squamous cell carcinoma vs. higher alpha-7 type prevalence in 80 adenocarcinoma), but not between 501 HIV-negative and 97 HIV-positive cases. With respect to types targeted, and/or cross-protected, by HPV vaccines, HPV16/18 accounted for 73%, HPV31/33/45/52/58 for an additional 22% and other HR-HPV types for 5%, of HPV-attributable cancer burden, with no significant difference by HIV status nor age. These data highlight the preventive potential of the ongoing national HPV vaccination program in Rwanda, and in sub-Saharan Africa as a whole. Importantly for this region, the impact of HIV on the distribution of causal HPV types was relatively minor, confirming type-specific relevance of HPV vaccines, irrespective of HIV status.

IFNL4 Genotypes Predict Clearance of RNA Viruses in Rwandan Children With Upper Respiratory Tract Infections

Polymorphisms in the interferon lambda gene locus (IFNL) such as the IFNL4 genetic variants rs12979860 and rs368234815 are predictive of resolution of hepatitis C virus infection, but information about the impact of these variants in other infections is scarce. This study aimed at determining the potential impact of IFNL4 variation for the clearance of respiratory tract pathogens in Rwandan children (≤5 years old, n = 480) seeking medical care for acute respiratory infections. Nasopharyngeal swabs were retrieved from all children at the first hospital referral and from 161 children at follow-up visits 2 weeks later. The swabs were analyzed for pathogens by real-time PCR and for host cell IFNL4 genotype at rs12979860 and rs368234815. Approximately 1/3 of the children were homozygous for the rs12979860 T allele and the rs368234815 ΔG allele, which are overrepresented in subjects of African descent. These IFNL4 variants were significantly associated with reduced clearance of RNA viruses. Our results suggest that IFNL4 genotypes that are common among subjects of African descent may determine inefficacious clearance of RNA viruses from the respiratory tract.

Cluster of Nasal Rhinosporidiosis, Eastern Province, Rwanda

We report 4 recent cases of nasal rhinosporidiosis in Rwanda. All patients were boys or young men living in the same district (Gatsibo District, Eastern Province), suggesting a reservoir in the area. The recent reemergence of rhinosporidiosis in Rwanda might reflect increased availability of diagnostic services rather than emerging disease.

Persistence rate of cervical human papillomavirus infections and abnormal cytology in Rwanda

OBJECTIVES

In this study, we determined the incidence and persistence of human papillomavirus (HPV) strains and of squamous intraepithelial lesions (SIL) or worse cytology in 237 HIV-positive and HIV-negative Rwandan women and whether the interleukin (IL)-28B single nucleotide polymorphism (SNP) at rs12979860 correlated with susceptibility to and persistence of HPV infection.

METHODS

Cervical samples were collected at baseline and after 9, 18 and 24 months for a 40-HPV DNA screening test and a ThinPrep Pap test. Genotyping of the IL-28B SNP rs12979860 was performed using real-time polymerase chain reaction (PCR).

RESULTS

Chronic high-risk (HR) HPV infections occurred in 56% of HIV-positive women, while no HIV-negative women developed HPV chronicity. High-grade SIL (HSIL) or cancer was diagnosed in 38% of HIV-positive women with persistent HR-HPV infections. HIV and HR-HPV positivity at baseline were factors associated with an increased risk of HPV persistence. Additionally, HR-HPV positivity at baseline was associated with an increased risk of developing HSIL or worse cytology. The unfavourable T/x genotype at rs12979860 is common among Africans, and women with this genotype were found to be more commonly infected with HPV.

CONCLUSIONS

HPV screening in Rwanda may help to identify women at risk of developing cervical cancer and polymorphism in IL-28B may be associated with risk of contracting  HPV infection.

Health Professional Training and Capacity Strengthening Through International Academic Partnerships: The First Five Years of the Human Resources for Health Program in Rwanda

BACKGROUND

The Rwanda Human Resources for Health Program (HRH Program) is a 7-year (2012-2019) health professional training initiative led by the Government of Rwanda with the goals of training a large, diverse, and competent health workforce and strengthening the capacity of academic institutions in Rwanda.

METHODS

The data for this organizational case study was collected through official reports from the Rwanda Ministry of Health (MoH) and 22 participating US academic institutions, databases from the MoH and the College of Medicine and Health Sciences (CMHS) in Rwanda, and surveys completed by the co-authors.

RESULTS

In the first 5 years of the HRH Program, a consortium of US academic institutions has deployed an average of 99 visiting faculty per year to support 22 training programs, which are on track to graduate almost 4600 students by 2019. The HRH Program has also built capacity within the CMHS by promoting the recruitment of Rwandan faculty and the establishment of additional partnerships and collaborations with the US academic institutions.

CONCLUSION

The milestones achieved by the HRH Program have been substantial although some challenges persist. These challenges include adequately supporting the visiting faculty; pairing them with Rwandan faculty (twinning); ensuring strong communication and coordination among stakeholders; addressing mismatches in priorities between donors and implementers; the execution of a sustainability strategy; and the decision by one of the donors not to renew funding beyond March 2017. Over the next 2 academic years, it is critical for the sustainability of the 22 training programs supported by the HRH Program that the health-related Schools at the CMHS significantly scale up recruitment of new Rwandan faculty. The HRH Program can serve as a model for other training initiatives implemented in countries affected by a severe shortage of health professionals.

Evaluation of human-papillomavirus testing and visual inspection for cervical cancer screening in Rwanda

BACKGROUND

A pilot screening campaign in Rwanda, based on careHPV-testing followed by visual inspection with acetic acid triage (careHPV+VIA triage), was evaluated against other WHO-recommended screening options, namely HPV screen-and-treat and VIA screen-and-treat.

METHODS

764 women aged 30-69 underwent at visit 1: i) VIA, and cervical cell collection for ii) careHPV in Rwanda, and iii) liquid-based cytology and GP5+/6+ HR-HPV PCR in The Netherlands. All 177 women positive by VIA, careHPV and/or PCR were recalled, of whom 84% attended. At visit 2, VIA was again used to triage screen-positive women for treatment and to obtain biopsies from all women either from visible lesions or at 12 o'clock of the squamocolumnar junction. Cross-sectional screening indices were estimated primarily against histological high-grade squamous intraepithelial lesions or worse (hHSIL+), after imputation of missing histology data, based on 1-visit or 2-visit approaches.

RESULTS

In a 1-visit screen-and-treat approach, VIA had sensitivity and specificity of 41% and 96%, respectively, versus 71% and 88% for careHPV, and 88% and 86% for PCR. In a 2-visit approach (in which hHSIL+ imputed among women without visit 2 were considered untreated) careHPV sensitivity dropped to 59% due to loss of 13% of hHSIL+. For careHPV+VIA triage, sensitivity dropped further to 35%, as another 24% of hHSIL+ were triaged to no treatment.

CONCLUSIONS

CareHPV was not as sensitive as gold-standard PCR, but detected considerably more hHSIL+ than VIA. However, due to careHPV-positive hHSIL+ women being lost to follow-up and/or triaged to no treatment, 2-visit careHPV+VIA triage did not perform better than VIA screen-and-treat.

Feasibility Study of Molecular Profiling of Gastric Cancer Specimens From Rwanda

Abstract 51

Background:

Gastric cancer is associated with high mortality in Rwanda. Geographic or genetic differences may lead to variations in somatic mutations and novel therapies. Overseas collaboration to determine gastric cancer molecular profiles is paramount. We undertook this work to determine the feasibility of collaboration between researchers in Rwanda and the United States by creating a research platform for gastric and other cancers in Rwanda.

Methods:

Patients consented for biopsy. Cases that were confirmed as gastric adenocarcinoma were included. Formalin-fixed paraffin-embedded tissue blocks or eight unstained sections (4 μm) were transported to the United States. DNA extraction and library preparation was performed by using 50 ng gDNA. Samples were normalized, pooled, and sequenced by using the Pillar NGS SLIMamp Lung Hot Spot Panel (Pillar Biosciences, Natick, MA). FASTq files were uploaded to Pillar Biosciences to perform sequence alignment, annotation, and variant classification.

Results:

Fifty-seven samples were received and 35 were excluded because of low DNA yield or quality (18 and 17, respectively). Mutations were detected in nine (41%) of 22 samples. One sample contained three mutations, other cases had one to two mutations identified. In total, 12 mutations were identified: TP53 (four), SMAD4 (two), ERBB4 (two; S341L and D228N), PTEN (two; K267RfsTer9 and C136Y), FBXW7 (one), and KRAS (one).

Conclusion:

Overseas collaboration for the molecular profiling of gastric cancer samples is feasible. Quality improved with larger biopsies or tissue blocks. Frequency of mutations is lower than expected. ERBB4 mutations identified are not known to be pathogenic. PTEN mutations are considered pathogenic—a potential target for therapy in larger trials. A larger fusion panel may be more effective in identifying potential targets. Funding: Pillar Biosciences provided reagents for sequencing.

AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST

Mary D. Chamberlin Research Funding: Pillar Biosciences Belson Rugwizangoga No relationship to disclose Francine B. DeAbreu No relationship to disclose Eric Rutaganda No relationship to disclose Vincent Dusabejambo No relationship to disclose Oswald Habyarimana No relationship to disclose Steve Bensen No relationship to disclose Gregory J. Tsongalis Honoraria: Roche, ChromaCode, Foundation Medicine, Physician Choice Labs Consulting or Advisory Role: Baystate Health System, Jackson Laboratory for Genomic Medicine (Inst) Research Funding: Qiagen, Illumina, QuanDx, Leica Biosystems, Abbott Molecular, Affymetrix

Coats' disease in Tanzania: first case report and literature review

BACKGROUND

Coats' disease is an exudative retinal detachment with vascular telangiectasis occurring mostly in male children, the age group most affected by retinoblastoma.

OBJECTIVES

Compare the differential diagnoses of Coats' disease Establish recommendation to early disease detection.

MATERIALS AND METHODS

A 3-year-old female child was referred to Muhimbili National Hospital (MNH), Tanzania, in September 2011. She had presented at the peripheral hospital with gradual onset of left eye leukocoria for 1 year and pain for 2 months. B-scan showed a mass in the left eye. A clinical diagnosis of retinoblastoma was made. Left eye enucleation was performed; the patient was referred to MNH, with the enucleated specimen.

RESULTS

Brain and orbits scan revealed no residual tumour. The globe measured 2 x 1.8 cm, the optic nerve stump measured 3 mm. A whitish mass filled the vitreous, with complete retinal detachment. Microscopy showed retinal gliosis, detachment with sub retinal PAS positive exudates, vacuolation and cholesterol clefts. Foreign body giant cells were present; telangiectatic thin-walled blood vessels were identified. Clinico-pathological findings were of stage 4 Coats' disease.

CONCLUSION

Coats' disease is an important differential diagnosis of retinoblastoma. Delay to detect Coats' disease leads to vision loss which necessitates eye enucleation as was in this child.

Pericardial cyst with right ventricular compression

Pericardial cysts are infrequent and benign mediastinal lesions. While most pericardial cysts are asymptomatic, some patients may present with compression symptoms. We present the case of a 22-year-old man who presented with a right pericardial cyst that caused compression of the right ventricle.