Abstract

Objective: Methotrexate (MTx) is an anticancer agent used in the treatment of various cancers. The objective of this study was to document the biodistribution of 99mTc-labelled Mtx (99mTc-MTx) in normal subjects and patients with breast cancers. Methods: We prepared the 99mTc-MTx kit by a direct labelling method and studied its biodistribution in volunteer subjects and patients with breast carcinoma breast. This clinical study was preceded by animal trials. Results: The normal biodistribution pattern in humans was characterized by nonspecific uptake in the body with the 99mTc-MTx behaving like a blood pool agent with no evidence of specific organ uptake. The kidneys were seen to be the main route of excretion. Biodistribution data of patients with carcinoma breast showed excellent tracer uptake in the tumour and showed no other nonspecific tracer uptake. Conclusion: This initial clinical trial showed that 99mTc-labelled anticancer drug can be successfully used for tumour scintigraphy, which appears to be a major breakthrough as this method of labelling and scanning may be useful in future tumour staging, calculating the sensitivity of tumours to certain anticancer agent and response evaluation during chemotherapy.