Question 1

How is breast cancer diagnosed based on its hormone receptor status?

Dr. Nithin S.G · Accepted Answer

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.

Question 2

How does mammography compare to MRI for diagnosing breast cancer?

Dr. Nithin S.G · Accepted Answer

MRI is definitely the better test, but it is not the standard first test. Mammography is a form of X-ray, and in young women, especially those under 30 to 35, it is not good at identifying a breast lump, so an ultrasound of the breast is preferred, with MRI as the next investigation if the ultrasound is inconclusive. After about 35 to 40 years of age, mammography becomes effective, and it is ideally advised in the older age group. MRI picks up more, but it costs more and involves more for the patient, whereas mammography is easy, which is why mammography is advised first. For staging, it is always better to go for a whole-body PET-CT scan, or a CT of the chest, abdomen and pelvis.

Question 3

How effective is immunotherapy compared to other cancer medications?

Dr. Nithin S.G · Accepted Answer

Immunotherapy is highly effective in the cancers and patients it suits, and its side effects are very few compared with 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.

Question 4

What specific investigation should be used to diagnose testicular cancer, given a case where ultrasound suggested cancer, radical orchiectomy was done, and the histology showed testicular tuberculosis?

Dr. Nithin S.G · Accepted Answer

Anyone presenting with a scrotal swelling should have an ultrasound, which will show a testicular mass or enlargement. There is no specific investigation that makes the diagnosis; confirmation comes only after orchiectomy. Testicular tuberculosis is possible, as in your case, but it is much less likely than cancer: of 100 patients with a testicular swelling, 80 to 90% will have cancer and only about 10% tuberculosis. For that majority it is better to go directly to orchiectomy, because if the swelling is a cancer, a biopsy will spread it. Tumour markers also help: yolk-sac tumours produce alpha-fetoprotein, choriocarcinoma and some seminomas produce beta-hCG, and LDH is also measured, and an elevated marker alongside the ultrasound finding is highly suggestive of cancer. My recommendation, whether or not the markers are raised, is orchiectomy rather than biopsy.

Question 5

How specific is PSA for prostate cancer, given a case where PSA was over 100 but the biopsy showed only BPH?

Dr. Nithin S.G · Accepted Answer

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 sensitive for prostate cancer, can confirm or rule out malignancy before treating for BPH alone.

Question 6

Should breast cancer be diagnosed with a core biopsy or an excisional biopsy?

Dr. Nithin S.G · Accepted Answer

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.

Question 7

Can precision oncology or targeted therapy offer a drug for uterine fibroids, since they are so common?

Dr. Nithin S.G · Accepted Answer

No specific genetic mutation has been identified for uterine fibroids, so there is no targeted drug against them. Uterine fibroids are not cancers; they are benign tumours, and treating them is outside my expertise. Treatment is hormonal therapy, surgery, or procedures such as uterine artery embolisation.

Question 8

What is your opinion on targeted therapy for advanced cancer patients with a poor performance status?

Dr. Nithin S.G · Accepted Answer

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.

Question 9

What is the difference between FNAC, core biopsy and excisional biopsy?

Dr. Nithin S.G · Accepted Answer

In FNAC (fine needle aspiration cytology), a needle is put into the tumour or a fluid-filled cyst and aspirated with a syringe. Fluid or blood comes out, carrying a few cells detached from the tumour, which are spread on a slide and examined under the microscope. Sensitivity is low because only a few cells may come. If abnormal cells are seen, the pathologist can say only that they are suggestive of cancer, not what type of cancer it is, and breast cancer today is classified into multiple types on histopathology. Breast cancer treatment also requires the hormone receptor status (ER, PR) and HER2 status, which must be tested on tissue, and the few cells from FNAC are not sufficient. In a core biopsy, a biopsy gun is pushed into the tumour and fired, and a cylindrical piece of tumour, around 1 cm long, comes out. That is sufficient for all the testing needed to make the diagnosis. So always do a core biopsy when you suspect cancer.

Live Discussion with Dr. Nithin S.G.