Interview with Dr Shelly Mahajan Role of Pathologists & Hereditary Cancer

Published on 09 Jul 2021

Dr Shelly Mahajan completed her Bachelor's in Medicine from LTM Medical College, Mumbai, post-graduation from Himalayan Hospital, Dehradun, and then served as a Visiting Scholar in Oncopathology at the University of Pennsylvania, Philadelphia. She is the Clinical Lead for Genomics at CARINGdx - Mahajan Imaging's advanced pathology lab in New Delhi. CARINGdx is one of the country's most advanced clinical genomics labs, equipped with a NextSeq and MiSeq system from Illumina. Dr Mahajan is responsible for all germline and somatic reporting of Next Generation Sequencing at CARINGdx and has recently built expertise in RT-PCR for COVID-19 testing and COVID-19 RNA sequencing.

Hereditary cancer

Hereditary or inherited cancers account for 10% of the total cancer cases reported. These cancers may run through the family line, making the members of a family susceptible to a particular type of cancer. The diagnosis of hereditary cancer relies more on a genetic mutation, which may lead to a higher risk of cancer susceptibility in a person. Knowing that a person is at risk of having hereditary cancer makes us capable of involving the person in more screening protocols. We can also access other family members of the patient to see if there is a susceptibility to getting cancer in the future in that person as well. This helps us to diagnose cancer at a very early stage. We say that early detection is secondary prevention. If a cancer diagnosis is early, it is better manageable with a better survival prognosis.

Is it wise to get a diagnostic test if someone in the family has cancer?

There are standard guidelines for such tests. These tests are not for everyone just because any member of the family has cancer. Factors like age and type of cancer play a decisive role in deciding whether to undergo screening or not. Not all cancers are hereditary cancers. When we say a family history of cancer, that means a strong family history, i.e., two or more relatives on the same side of the family.

test cancer

So, if someone has one relative on the mother's side and one on the father's side of the family having cancer, then that will not put the person in a high-risk category. When we talk about family history, we consider many details like how many people in the family had cancer, at what age and the type of cancer. If the diagnosis was at 70 years of age, then it may not be high-risk cancer. But if even one case gets diagnosed at the age of 30, then that will be regarded as a high-risk category. Therefore, taking a detailed history becomes very important.

Genes, and their importance in cancer

Genes are coded messages for the cell, which tells the cell how to behave. If the genes are faulty or mutated, then the messages they send will also be faulty, and it will result in abnormalities and eventually, diseases. Therefore, these faulty genes, in a way, tell the cells to become cancerous. So, based on the kind of faults that exist in the genes, the treatment is decided.

BRCA genes

BRCA 1 and BRCA 2 are the two most commonly associated genes with hereditary cancer. The myth is that BRCA mutation is only associated with breast cancer, but that's not true. BRCA mutation is associated not just with Breast Cancer but with multiple cancers like ovarian cancer, Pancreatic Cancer and Prostate Cancer. BRCA 1 and BRCA 2 are the two different genes that have been well studied and well-proven to be associated with hereditary cancer, but that does not mean that only these genes are associated with hereditary cancer. Apart from these two, there are more than 30-32 genes that are associated with hereditary cancer.

Genetic testing

There are two kinds of cancer. One is hereditary cancer, and the other is acquired cancer. Acquired cancer is also caused by gene mutation, but those mutations are not present in your body by birth or in your family; they are acquired during your lifetime through activities such as smoking or environmental factors such as pollution. Genetic testing in both these cancers is different. For hereditary cancer, we go for a blood test, but if we want to look for a kind of mutation in a particular tumour to determine the treatment, then we take the tissue samples. So, in germline testing, we take a person's DNA, while in somatic testing, we test the DNA of the cancerous tumour.

Challenges faced by a Pathologist

Generally, it is always challenging, since the treatment plan by the clinician is planned relies on the results that we give, which makes it vital that we give nothing but the most accurate results. In the germline part, technically, things have now become very streamlined, it's an ever-improving technology, with the best equipment and software. So the challenges we face are in convincing the patient and explaining to them the implications of tests. We have to tell the patients in both phases, not to be disheartened and not to be too happy. Tissue accessibility to get the DNA, its interpretation, counselling and discussing the test results with patients, is always challenging.

The role of Pathologist and Radiologist in diagnosing cancer

The primary role of the Pathologist and Radiologist is to convey the right information to the treating doctor. Radiology is seeing the images and making the diagnosis. It is less invasive.

pathologist and radiologist

In Pathology, we directly test whatever is in the radiology report. As a Pathologist, if I can get some extra information, it will help in the proper diagnosis. In some cases, we need to work hand in hand. There are certain tissues which are inaccessible, but you need to do the biopsy, so that's where the radiologist and Pathologist work together in image-guided biopsies. In the end, it's all a collective team effort to provide the proper diagnosis of a patient.

The importance of biopsy

Even if we are sure by radiology or an FNAC, a Biopsy is necessary to confirm the diagnosis. There could be lesions that one can clinically or radiologically confirm to be cancer, but cancer is a life-changing diagnosis.

The patient and family will have to go through an emotional journey, so we have to be 100% sure. Also, a Biopsy will help in subtyping cancer as nowadays the treatment has become so specific that understanding which subtype it belongs to, will make a difference in the treatment plan.

The information in a Pathology report

We need to tell the doctor whether the cancer is there is not, where the cancer is arriving from, and how much the cancer has spread. Also whether the amount of tissue removed is enough, or if there is still some cancer left in the body. A basic pathology report should ideally include these details.

Proper nutrition and a healthy lifestyle

Nutrition has to be generally healthy; high protein, high fibre, low carbohydrate diet, lots of fluids, with some mindful walking, exercise and some meditation. Ultimately this will improve your immunity which may not help in preventing cancer but will help in fighting it better.

Stigmas and myths related to cancer

I feel it's high time that we start talking about cancer, mainly Breast Cancer and Ovarian Cancer. Even today, nobody wants to disclose that they have Breast Cancer in the family. We need to understand that it's just another disease and has a cure. All cancers are not hereditary, and we just need to be aware of the risk factors. Do self-examination regularly, and once you feel something, then don't delay it, just go to a doctor. Please don't be scared of cancer because we are lucky to be living at a time where cancer can be dealt with very well thanks to the advancements in medical science.

Watch the parts of the interview on the links below: