Why Biopsy Beats FNAC in Cancer Diagnosis

PSA is not specific for prostate cancer at all, no tumour marker is specific for any single cancer. An elevated PSA in a patient with a prostatic mass could reflect BPH or cancer, and can rise even after a digital rectal exam or ejaculation. Very high values, such as over 100, are more suggestive of cancer, so if PSA is extremely elevated yet the biopsy shows only BPH, the biopsy may simply have missed the cancerous core, which does happen. In such suspicious cases, a gallium-68 PSMA PET scan, highly specific for prostate cancer, can help confirm or rule out malignancy before treating for BPH alone.

Core needle biopsy is sufficient for breast cancer, and there is no need for excisional biopsy in most cases. For a small tumour such as a fibroadenoma, excisional biopsy is an option, but core needle biopsy is equally effective, and if the mass proves benign, surgery can be avoided altogether.

Unfortunately there is no specific genetic mutation identified for uterine fibroids and no targeted drug role for them, since fibroids are benign tumours, not cancers. Treatment options remain limited to hormonal therapy or surgery.

Targeted therapy's main advantage is that it is mostly oral medication without the classic side effects of chemotherapy, so it remains a reasonable option even in poor performance status, though this depends on the specific drug and its side-effect profile rather than being a blanket rule. Two cases illustrate this: a metastatic lung cancer patient with brain metastases who was bedridden with severe headache and vomiting, and a metastatic breast cancer patient with cerebellar metastasis causing incoordination, both showed marked improvement on targeted therapy despite their poor baseline state. Overall, more patients in poor performance status can be treated with targeted therapy than with chemotherapy, since chemotherapy is often not feasible in a very poor clinical state.

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.

FNAC yields too few cells for a pathologist to identify the exact cancer subtype or run hormone receptor and genetic tests, and it can rupture the tumour capsule during sampling.

Because lymphoma specifically cannot always be diagnosed if the node's capsule is broken during sampling, so the whole node is removed intact wherever it is surgically accessible.

A kidney mass, a testicular swelling, a cirrhotic liver mass with elevated AFP, and retinoblastoma in children are all managed without a diagnostic biopsy, since biopsy itself risks spreading the disease in these cases.