Detection of HPV16 in Esophageal Cancer in a High-Incidence Region of Malawi.

This study was designed to explore the role of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC). Fifty-five patients receiving diagnostic upper gastrointestinal endoscopy at Zomba Central Hospital or Queen Elizabeth Hospital in Blantyre (Malawi) in 2010, were included in our study. Formalin-fixed paraffin-embedded biopsies were collected for histopathological diagnosis. HPV DNA was detected using multiplex Quantitative PCR (qPCR) and in situ hybridization (ISH). p16INK4a staining served as a surrogate marker for HPV oncogene activity. Cell proliferation was determined by Ki-67 staining. Human immunodeficiency virus (HIV) status was evaluated by serology. Data on the consumption of alcohol and tobacco, and history of tuberculosis (TBC), oral thrush, and Herpes zoster, were obtained by questionnaire. Forty patients displayed ESCC, three displayed dysplastic epithelium, and 12 displayed normal epithelium. HPV16 was detected in six ESCC specimens and in one dysplastic lesion. Among HPV-positive patients, viral load varied from 0.001 to 2.5 copies per tumor cell. HPV DNA presence could not be confirmed by ISH. p16INK4a positivity correlated with the presence of HPV DNA (p = 0.03). Of particular note is that the Ki-67 proliferation index, in areas with diffuse nuclear or cytoplasmatic p16INK4a staining ≥50%, was significantly higher in HPV-positive tumors compared to the corresponding p16INK4a stained areas of HPV-negative tumors (p = 0.004). HPV infection in ESCC was not associated with the consumption of tobacco or alcohol, but there were significantly more patients drinking locally brewed alcohol among HPV-positive tumor patients compared to non-tumor patients (p = 0.02) and compared to HPV-negative tumor patients (p = 0.047). There was no association between HIV infection, history of TBC, Herpes zoster, oral thrush, or HPV infection, in ESCC patients. Our indirect evidence for viral oncogene activity is restricted to single tumor cell areas, indicative of the role of HPV16 in the development of ESCC. The inhomogeneous presence of the virus within the tumor is reminiscent of the "hit and run" mechanism discussed for ß-HPV types, such as HPV38.

Self-expanding metal stents (SEMS) for patients with advanced esophageal cancer in Malawi: an effective palliative treatment.

BACKGROUND AND OBJECTIVES: Esophageal cancer is common in Malawi and most patients are inoperable at time of diagnosis. The aim of this study was to prospectively evaluate palliative treatment with self-expanding metal stents (SEMS) in Malawi, a low-income country with limited medical resources. METHODS: Data of patients with advanced inoperable esophageal cancer were prospectively collected. Tumor and patient specifics, risk factors, dysphagia scores, complications, and survival were assessed. Follow-up data for 1 year or until death were collected from 118/143 patients (83%) during clinic visits, home visits, or via cell phone. RESULTS: One hundred forty-three patients were treated with 154 SEMS. Median survival was 210 days (95% CI: 150-262 days). Fourteen of 118 patients with complete follow-up (11.9%) survived more than 1 year with longest documented survival of 406 days. The median dysphagia score improved from 3 at the time of presentation to 0 at the time of death. Early complications occurred in 4.2% (6/143), late complications in 11.9% of patients (14/118). The procedure related mortality was 2.1% (3/143). CONCLUSIONS: SEMS is an appropriate palliative treatment in a resource-limited environment. For the vast majority of patients a single intervention provides lasting improvement of dysphagia.

Helicobacter pylori, HIV and Gastric Hypochlorhydria in the Malawian Population.

BACKGROUND: HIV and Helicobacter pylori are common chronic infections in sub-Saharan Africa. Both conditions can predispose to gastric hypochlorhydria that may be a risk factor for enteric infections and reduced drug absorption. We have investigated to what extent HIV and H. pylori infections are associated with hypochlorhydria in a Malawian cohort of patients undergoing endoscopy. METHODS: 104 sequential symptomatic adults referred for gastroscopy at Queen Elizabeth Central Hospital, Blantyre, Malawi, had blood taken for rapid HIV testing and fasting serum gastrin analysis. Gastric fluid was aspirated for pH testing, and gastric biopsies were taken. RESULTS: After 9/104 HIV-infected patients who were already established on anti-retroviral therapy were excluded, 17/95 (25.0%) were seropositive for untreated HIV, and 68/95 (71.6%) patients were H. pylori positive by histology. Hypochlorhydria (fasting gastric pH>4.0) was present in 55.8% (53/95) of patients. H. pylori infection was significantly associated with hypochlorhydria (OR 2.91, [1.02-7.75], p=0.046). While single infection with HIV was not significantly independently associated with hypochlorhydria. H. pylori and HIV co-infection was more strongly associated with hypochlorhydria (OR 6.25, [1.33-29.43], p=0.020) than either infection alone, suggesting an additive effect of co-infection. HIV infection was associated with higher serum gastrin levels (91.3 pM vs. 53.1 pM, p=0.040), while H. pylori infection was not (63.1 pM vs. 55.1 pM, p=0.610). Irrespective of H. pylori and HIV status, most patients (>90%) exhibited pangastritis. Only three patients had histological evidence of gastric atrophy, of which only one was HIV-infected. CONCLUSION: H. pylori infection was associated with fasting hypochlorhydria, while HIV was not independently associated. HIV and H. pylori co-infection, however, was more strongly associated with hypochlorhydria than H. pylori infection alone. The mechanism of this apparent additive effect between HIV and H. pylori remains unclear, but appears to be related to chronic pangastritis rather than gastric atrophy, and associated with hypergastrinaemia in HIV-infected individuals.