UADT cancers

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					UADT cancers
Interim results

Databases searched Search results filtered Papers identified & obtained for full review Data extraction

Databases: English Databases: Spanish

Databases: Chinese


 


Independent Quality Assessment Cross-checking references & citations Meta-analysis

 Awaited

Interim results only

The combined organs and tissues of the respiratory tract and the upper part of the digestive tract (including the lips, mouth, tongue, nose, throat, vocal cords, and part of the esophagus and windpipe).

Search strategy
• “Nasopharynx” OR “nasopharyngeal” OR “NPC” OR “Oropharynx” OR “oropharyngeal” OR “Hypopharynx” OR “hypopharyngeal” OR “pharynx” OR “larynx” OR “laryngeal” OR “paranasal” OR “head and neck” OR “UADT” OR “aerodigestive” OR “upper respiratory” OR “ENT” OR “otorhinolaryngologic*” • Cancer OR cancers OR carcinoma OR carcinomata OR neoplasm OR neoplasms OR tumor OR tumors OR tumour OR tumours • "IAP" OR "Indoor air" OR "pollution" OR "pollutant" OR "fuel" OR "fuels" OR "dung" OR "agricultural waste" OR "crop waste" OR "crop residue" OR "charcoal" OR "coal" OR "biomass" OR "wood" OR "stove" OR "stoves" OR "chula" OR "chulla" OR "oven" OR "ovens" OR "smoke" OR "smoky" OR heat* OR cook* OR light* OR burn*

• • • • • • • • • • PubMed (Medline) Embase (Scopus & Ovid) Cochrane Controlled Trials Register CINAHL (Ovid) Global Health (Ovid) DARE (Database of Abstracts of Reviews of Effects) – for reviews LILACS (Latin American and Caribbean literature) Scielo Index Medicus Africanus Chinese databases CNKI – by Ray Liu @UCB

Search results (English)
• • • • • 11,627 search results 703 abstracts screened 55 full papers reviewed 9 papers with relevant data Did not capture all references from IARC monograph – 2 or 3 additional papers • Need to cross-check references and citations plus await results from Chinese databases

9 studies
• 3 China, 1 Singapore, 1 Malaysia, 2 India, 1 Germany, 1 Brazil
– 1 kerosene exposure only (not for M/A) – 2 insufficient data for M/A Armstrong 1983, Shanmugaratnam 2000

Cancer site Nasopharyngeal cancer Studies Zheng 1994, Chelleng 2000, Armstrong 1983, Shanmugaratnam 2000 Zheng 1992

Nasal cavity, paranasal sinuses and middle ear

Oral cavity/hypopharynx/ larynx -mainly SCC carcinomas

Dietz 1995, Zheng 1992b, Pintos 1998, Sapkota 2008

Exposure assessment
Indirect assessment Current use of wood for cooking Use of wood as domestic fuel in 1 year preceding diagnosis Always use wood for cooking Always use coal for cooking Ever use wood/straw OR coal OR kerosene as cooking fuel Main cooking fuel for last ten years – charcoal, firewood, kerosene Study Chelleng 2000, Zheng 1994; Sapkota 2008 Zheng 1992 Shanmugaratnam 2000 (not for M/A)

“Exposure to domestic smoke”
Current use wood stove for heating or cooking Use fossil fuel stove for heating Use fossil fuel stove for cooking Ever use kerosene stove

Armstrong 1983 (not for M/A)
Pintos 1998 Dietz 1995 Zheng 1992b (not for M/A)

Quality Issues
Shanmugaratnam 2000

Quality issues
Insufficient data to use for metaanalysis

Exposure – main cooking fuel (firewood/kerosene /charcoal) used over last ten years but no clear comparison category Only OR and chi2 provided

Armstrong 1983 Malaysia Zheng 1992b Dietz 1995 Heidelberg, Germany Zheng 1992 Zheng 1994 Chelleng 2000: Nagaland, India

“No positive association with domestic smoke” – no data provided Crude data for use of kerosene stove Use of fossil fuel single stoves for cooking or heating – combines clean and solid fuels Ever use of wood/straw as cooking fuel No clear comparison fuel Use of wood as domestic fuel 1 year preceding diagnosis No clear comparison fuel Cooking fuel used gas vs. wood– 72% of cases were men and a lot of cooking was done outside main home

Insufficient data to use for metaanalysis No other comparable study therefore not included in M/A Remove in sensitivity analysis

Remove in sensitivity analysis Remove in sensitivity analysis ? Remove in sensitivity analysis

Sapkota 2008

Always coal or Always wood for cooking vs. modern fuel. But 93% larynx ca and 83% hypopharynx cases men.

? Remove in sensitivity analysis

All studies (n=6)

Publication Bias
• • • • • • • • • • • • • • • • • • Begg's Test adj. Kendall's Score (P-Q) = 20 Std. Dev. of Score = 14.58 Number of Studies = 12 z = 1.37 Pr > |z| = 0.170 z = 1.30 (continuity corrected) Pr > |z| = 0.193 (continuity corrected) Egger's test -----------------------------------------------------------------------------Std_Eff | Coef. Std. Err. t P>|t| [95% Conf. Interval] -------------+----------------------------------------------------------------------+-----slope | .0139528 .2934942 0.05 0.963 -.6399932 .6678987 bias | 2.185734 1.016875 2.15 0.057 -.0800038 4.451472 ------------------------------------------------------------------------------

NPC (n=2)

NPC plus nasal cavity/middle ear n=3

Excluding nasopharynx (n=3)

Key assumptions/issues
• Heterogeneous outcomes • Combine fuel categories
– Fossil fuel stoves

• Unclear reference categories
– Ever wood vs. never wood

• Cooking as exposure when most of subjects are men