Circulating tumor cells demonstrate a positive biomarker in head and neck squamous cell carcinoma (HNSCC) in tobacco consuming population of Bangladesh.
Authors: D'Souza Alain , Hossain Muhammad Mosaraf , Jayant Sreeja , Gore Isha , Chakraborti Pratim , Gourishankar Aland , Singh Balram , Arora Smriti , Tripathi Swati , Singh Nitin , Badave Reecha , Chowdhury Mohammad Ali Asgar , Shil Rajib Kumar , Islam Shafiqul , Ahmed Ridwan , Majumder Mohit , Chowdhury Srikanta , Noman Abu Shadat Mohammod , Chaturvedi Pankaj , Khandare Jayant 
Published: June 2021

e18011 Background: Tobacco consumption accounts for 1.6 million deaths annually in the South East Asia Region (SEAR). Notably, amongst 10-20% of the global population consuming the betel quid and tobacco, about 81% concentration is in SEAR regions, including India and Bangladesh. The prevalence of HNSCC in these regions is rising alarmingly. For example, HNCs account for 23% of total 156775 cancer incidences in Bangladesh. Liquid biopsy tools are unavailable and expensive for most patients in this region. However, early cancer detection using tumor biomarkers, for example, Circulating Tumor Cells (CTCs) is highly implicated. Furthermore, such biomarkers are being validated and have potential for screening of high-risk patients, such as genetic predisposition, tobacco consumption, etc. We report the first observational study in HNSCC patients in Bangladesh correlating the presence of CTCs to chronic tobacco consumption. Methods: The study involved 70 cancer patients and 10 healthy volunteers (no prior cancer history). 87% of the patients had a specified history of chronic tobacco consumption. CTCs were isolated in 1.5 ml of blood using OncoDiscover Liquid Biopsy Test, which is clinically approved by the Drug Controller General of India, that contains an enriching anti-EPCAM antibody immunomagnetic kit. CTCs are qualified as CK18+, DAPI+and CD45-. Subsequently, CTCs were imaged using Zeiss Axio Observer 7 and quantified for Mean Fluorescence Intensity (MFI) for clinicopathological parameters; age/gender, HNSCC sub-population, and CTC distribution. Results: This is the 1st study on Bangladesh phenotype accounting for the presence of CTCs in HNSCC patients. In this population, 34 males (66%) and 10 females (52%) accounted for 91 CTCs. CTC distribution was 0 to 6 with mean and median ̃ 2.02 and 2, respectively. 25 patients (17 males, 8 females) were negative for any CTCs. Interestingly, 02 patients exhibited CTC clusters indicative of aggressive metastasis in which 01 patient had no prior tobacco usage or family cancer history. There was no correlation between CTC presence in males (66 %) and females (52 %). Healthy volunteer samples exhibited no false positives. The MFI values ranged between 23 and 766, with mean and median MFI values were 157 and 96, respectively, indicative of CK overexpression on CTCs of HNSCC patients. Conclusions: HNSCC patients with a history of chronic tobacco consumption in Bangladesh correlated the presence of CTCs in 64 % of the cases. Prospectively, CTCs may be validated as a biomarker for screening chronic tobacco users in Bangladesh to detect early cancers and HNSCC. Clinical trial information: BMRC/Grants/2018/99 (1-100).