Radiologist — Medical Specialist in Diagnostic Imaging

A radiologist is a qualified physician who has undertaken comprehensive postgraduate specialist training in interpreting medical images and performing image-guided procedures. They understand the physical principles of various imaging modalities, radiobiology, and the radiographic presentation of benign and malignant disease processes across all human organ systems.

Radiologists produce detailed clinical reports that evaluate tumour size, precise location, local tissue invasion, and distant spread. Diagnostic radiologists focus primarily on interpreting studies like computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), mammography, and ultrasound. Interventional radiologists, a subspeciality, use real-time imaging guidance to carry out minimally invasive procedures such as biopsies, vascular stenting, and tumour ablations.

Accurate cancer staging and treatment evaluation depend fundamentally on the radiologist's findings. Their reports determine whether a tumour can be surgically removed, whether systemic treatment is shrinking a mass, or whether there is evidence of recurrence during surveillance. By catching changes early and ensuring clear communication within multidisciplinary tumour boards, radiologists help make sure that treatment decisions are based on accurate physical evidence.

Radiologists work with and interpret imaging tests rather than administering biological assays. They examine imaging modalities including CT, MRI, PET, digital mammography, and ultrasound, and assess imaging biomarkers such as fluorodeoxyglucose (FDG) uptake on PET scans. Interventional radiologists also perform image-guided core needle biopsies to obtain tissue for essential histopathological and molecular analysis.

Radiologists are involved in the management of almost every cancer type. They are instrumental in diagnosing and staging breast cancer via mammography and MRI, lung cancer via low-dose CT scans, colorectal cancer with pelvic MRI and abdominal CT, and brain tumours. They also evaluate lymphoma, prostate, kidney, liver, pancreatic, and musculoskeletal cancers across all clinical stages.

Radiology reports guide surgical planning by showing tumour boundaries and blood vessel involvement. They determine systemic therapy efficacy using standardised frameworks like RECIST (Response Evaluation Criteria in Solid Tumors). Interventional radiologists also deliver direct cancer treatments, including radiofrequency ablation, microwave ablation, and transarterial chemoembolisation (TACE), providing targeted therapy for patients unsuitable for conventional open surgery.