Missing and decayed teeth, oral hygiene and dental staining in relation to esophageal cancer risk: ESCCAPE case-control study in Kilimanjaro, Tanzania.

In the African esophageal squamous cell carcinoma (ESCC) corridor, recent work from Kenya found increased ESCC risk associated with poor oral health, including an ill-understood association with dental fluorosis. We examined these associations in a Tanzanian study, which included examination of potential biases influencing the latter association. This age and sex frequency-matched case-control study included 310 ESCC cases and 313 hospital visitor/patient controls. Exposures included self-reported oral hygiene and nondental observer assessed decayed+missing+filled tooth count (DMFT index) and the Thylstrup-Fejerskov dental fluorosis index (TFI). Blind to this nondental observer TFI, a dentist independently assessed fluorosis on photographs of 75 participants. Odds ratios (ORs) are adjusted for demographic factors, alcohol and tobacco. ESCC risk was associated with using a chewed stick to brush teeth (OR 2.3 [95% CI: 1.3-4.1]), using charcoal to whiten teeth (OR 2.13 [95% CI: 1.3, 4.1]) and linearly with the DMFT index (OR 3.3 95% CI: [1.8, 6.0] for ≥10 vs 0). Nondental observer-assessed fluorosis was strongly associated with ESCC risk (OR 13.5 [95% CI: 5.7-31.9] for TFI 5+ v 0). However, the professional dentist's assessment indicated that only 43% (10/23) of participants assessed as TFI 5+ actually had fluorosis. In summary, using oral charcoal, brushing with a chewed stick and missing/decayed teeth may be risk factors for ESCC in Tanzania, for which dose-response and mechanistic research is needed. Links of ESCC with "dental fluorosis" suffered from severe exposure misclassification, rendering it impossible to disentangle any effects of fluorosis, extrinsic staining or reverse causality.

Challenges of Maintaining Good Clinical Laboratory Practices in Low-Resource Settings: A Health Program Evaluation Framework Case Study From East Africa.

OBJECTIVES: Using a clinical research laboratory as a case study, we sought to characterize barriers to maintaining Good Clinical Laboratory Practice (GCLP) services in a developing world setting. METHODS: Using a US Centers for Disease Control and Prevention framework for program evaluation in public health, we performed an evaluation of the Kilimanjaro Christian Medical Centre-Duke University Health Collaboration clinical research laboratory sections of the Kilimanjaro Clinical Research Institute in Moshi, Tanzania. Laboratory records from November 2012 through October 2014 were reviewed for this analysis. RESULTS: During the 2-year period of study, seven instrument malfunctions suspended testing required for open clinical trials. A median (range) of 9 (1-55) days elapsed between instrument malfunction and biomedical engineer service. Sixteen (76.1%) of 21 suppliers of reagents, controls, and consumables were based outside Tanzania. Test throughput among laboratory sections used a median (range) of 0.6% (0.2%-2.7%) of instrument capacity. Five (55.6%) of nine laboratory technologists left their posts over 2 years. CONCLUSIONS: These findings demonstrate that GCLP laboratory service provision in this setting is hampered by delays in biomedical engineer support, delays and extra costs in commodity procurement, low testing throughput, and high personnel turnover.