Immunotherapy: Retraining the Immune System to Fight Cancer

FNAC (fine needle aspiration cytology) involves inserting a needle into a tumour or fluid-filled cyst and aspirating fluid along with a few detached cells for slide evaluation under a microscope; sensitivity is low since so few cells come through, and a pathologist can typically only confirm abnormal cells are present, not the exact cancer subtype needed for hormone receptor and HER2 testing. Core biopsy uses a biopsy gun that removes a cylindrical piece of tissue roughly a centimetre long, providing enough tissue for full histopathological and genetic workup, which is why core biopsy, not FNAC, is preferred whenever cancer is suspected.

Breast cancer is broadly split into three types: hormone receptor positive, HER2 positive, and triple negative. The diagnostic procedure itself does not change based on subtype: a biopsy is still required, with mammography used only for initial evaluation. IHC testing on the biopsy sample determines ER, PR and HER2 status; if all three come back negative, the cancer is classed as triple negative, a more aggressive subtype that is harder to treat once it reaches stage four.

Neither is simply better in every case. MRI is the more definitive test to rule out cancer, but mammography, a form of X-ray, can miss a tumour hidden in fattier breast tissue, which is common in women under 30 to 35. In younger women, ultrasound or MRI is preferred; mammography becomes more effective after around 35 to 40, once fibrous tissue outweighs fat. MRI is more accurate but costlier and more involved for the patient, which is why mammography is offered first, with a PET-CT or a CT of the chest, abdomen and pelvis used for staging.

Immunotherapy is highly effective and carries far fewer side effects than standard chemotherapy. In cancers with a large initial tumour burden, such as lung cancer, it is usually combined with chemotherapy at first, since immunotherapy alone takes time to bring a heavy disease burden under control. Once the disease responds, treatment continues on immunotherapy alone to maintain that response.

Any scrotal swelling should first be evaluated with ultrasound, which will show a testicular mass or enlargement, but there is no test that gives a confirmed diagnosis before surgery, that only comes after radical orchiectomy. Of 100 patients presenting with a testicular swelling, roughly 80 to 90 percent will have cancer and about 10 percent tuberculosis, so for the large majority a biopsy is avoided, since it risks spreading the cancer, in favour of going directly to orchiectomy. Tumour markers such as AFP and beta-hCG, elevated in seminoma and yolk-sac tumours, can support the ultrasound finding, but the standard recommendation regardless of marker levels is orchiectomy rather than biopsy.

Immunotherapy reprogrammes the patient's own immune system to recognise and attack cancer cells that had been evading it, rather than acting directly on rapidly dividing cells the way chemotherapy does.

In cancers with a large initial tumour burden, immunotherapy alone can take too long to bring the disease under control, so chemotherapy is added initially and dropped once the disease responds.

A repeat scan after six cycles of immunotherapy showed no evidence of disease anywhere, and the complete response has held for several years since.