Author(s): Bhat Abdul Rashid, Muhammed Afzal Wani, A.R. Kirmani, T.H. Raina, A.U. Ramzan, Shafiq Alam, Anil Dhar, Sajad Arif , Sheikh Javed
The objective of this hospital based study was to determine the relationship between the pa-tients of primary malignant brain tumors and their occupation. Retrospectively case files (and death certificates) of 432 patients of primary malignant brain tumors and 457 controls (non-tumor neurologic diseases), admitted simultaneously over a period of 4 years from Jan., 2005 to Dec., 2008, to the Neurosurgery, Sher- I -Kashmir Institute of Medical Sciences (SKIMS), Kashmir were studied. Each passing year showed an increase in the incidence of new cases of highly malignant brain tumors like glioblastoma multiforme and medulloblas-tomas, most i.e. 29.30% (114 out of 389) patients in 2008 as compared to 20.82% (81 out of 389) patients in 2005. The pesticide use in the Kashmir-Valley has increased ten-fold for the last 20 years. Analysis revealed that 90.04% (389 out of 432) patients were orchard farm workers, pesticide mixers, sprayers, foggers, orchard residents and orchard playing chil-dren exposed to the high levels of multiple types of neurotoxic and carcinogenic (chlor-pyriphos, dimethoate, mancozeb and captan) chemicals as pesticides, fungicides and insecti-cides for a duration of 10 to 30 years. About 61.18% had direct and 38.81% had indirect exposure. The 58.61% (228 out of 389) orchard-farm patients had pesticide exposure at an age of 19 to 40 years. Most of the orchard-farm patients i.e. 44.47% (173 out of 389) had spent 10 to 20 years of life exposed to pesticides directly and/or indirectly and 70.52% (122 out of 173) were males. About 73.00% (284 out of 389) orchard-farm patients presented with symptoms and signs related to brain cancer at the age of 21 to 60 years and most of these 56.33% (160 out of 284) at the age between 41 to 60 years of life. The 9.96% (43 out of 432) patients were not exposed to pesticides. On the other hand only 119 patients out of 457 controls had recorded history of pesticide exposure and 338 were unrelated to pesticides. Familial gliomas emerged in three families. All orchard-farm related 389 patients had high grade tumors as compared to the non-orchard farm tumors. Mortality in orchard-farmer tumors exposed to pesticides was 12%. The 31.9% (124 out of 389) orchard-farm workers with higher (> 6334 u/l} levels of SCE were below 40 years and had pesticide exposure of 10 to 20 years from an early age. This was postulated to be due to chronic exposure to organo-phosphates, exposure to many other carcinogenic pesticides and non-cholinergic mechanism of action of organophosphates than the one that depresses the levels of acetyl cholinesterase (AChE) as in acute poisoning. However exact mechanism by which pesticides cause brain cancer needs experimental models in future. The study shows significant Case / Control (Odds Ratio) OR of 0. 28 ; hospital controls SCE (serum cholinesterase) Odds Ratio of 1.1 and family control SCE OR of 1.5.