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Objective.To demonstrate the medical physics activities in treatment of carcinoma cervix in B.P.Koirala Memorial Cancer Hospital(BPKMCH),Bharatpur,Nepal.Methods:Mega voltage external beam radiation therapy(EBRT)combined with(ICR)is the standard radio therapeutic management for the patients with carcinoma cervix.Patients have advantage of 6MV and 20 MV photons from linear accelerators compared with Tele cobalt beam.Vari source HDR machine with single Iridium-192 source wire of 5 mm length diameter 0.38 mm with half-life of 74 days requires source change in every 4 months.BPKMCH has its own protocol to prescribe total dose,time and fractionation will be discussed with its biologically effective dose.The physical aspects of the machine,ICR application,orthogonal simulation images import,and ICRU-38 point A,B,rectum and bladder point definition followed for dosimetry.Source activity measurement,quality assurance test,position verification,radiation protection and physics specific concerns and final check list followed.Clinicians must communicate about tumor volume to planning physicist so that he can optimized plan with pear shaped covering the diseased volume.Results:On site source strength measurements is within standard deviation of 0.6.The dose to rectum and bladder points is accepted between 60 to 70%of dose of point A and dose to Point B is about 25%of A.QA results and different pear shapes shown.Benefits are shorter treatment time,treatment on outpatient basis,less discomfort reduced risk of applicator displacement and safe practice.Conclusions:It is a vital clinical tool and 6/7 patients are treated daily.To tailor the dose according to shape of tumor volume is still a challenge in 2D.