ABSTRACT: What is disclosed is a system and method for isolating blood vessels in a thermographic image of a patient’s breast or any other muscular region of the body. A thermographic image of a patient is received. A temperature-based analysis is performed on the image to detect vessel pixels. An intensity-based method analysis is performed on the image. A shape-based analysis is also performed to detect pixels of vessel-like structures. Candidate pixels which satisfy one or more of intensity-based or temperature-based or shaped-based criterion are identified. A constraint of local maximallity is thereafter imposed on each candidate pixel that satisfies both criterion to eliminate spurious non-vessel pixels. Candidate pixels which satisfy both criterion are then marked with a different color such that the vessel structures in the breast tissue can be visually differentiated. The vessel structures are provided to a classifier system which classifies the tissue in the thermal image as malignant and non-malignant otherwise, based on a tortuosity of the vessel structures.