Why Does Cancer Come Back? A Breast Surgeon Explains After Tahira Kashyap’s Relapse

When author and filmmaker Tahira Kashyap recently shared that her breast cancer had returned years after she first battled it, it raised a critical question in the minds of many: Why does cancer come back, even after seemingly successful treatment?

According to Dr. Swathi Prakash, Associate Consultant - Breast Surgery, Cancer Centre, Rela Hospital, Chennai, the answer lies in the nature of cancer itself.

“The truth is, cancer is a complex disease known not just for its aggressiveness, but for its unpredictability,” she explains.

“Even after a tumour is treated and removed, there's always a risk—however small—of it returning. This recurrence can happen in the same location as the original tumour, in nearby lymph nodes, or in distant parts of the body that were not affected during the initial diagnosis.”

Why Recurrence Happens

The most common reason cancer returns is due to microscopic cancer cells that survive the initial treatment. These cells can remain dormant—essentially in a "sleep mode"—and are often undetectable by current scans or tests. Over time, they may reactivate and begin to grow again, leading to recurrence.

According to Dr. Prakash, other contributing factors include:

• Resistance to initial therapies such as chemotherapy or radiation
• Spread of cancer cells through lymphatic or blood vessels
• Aggressive subtypes like triple-negative or HER2-positive breast cancers
• Genetic mutations that make the cancer more resilient
• A higher initial stage of the disease at the time of first diagnosis

Because of these complexities, breast cancer treatment often requires a multimodal approach—combining surgery, chemotherapy, radiation, hormonal therapy, targeted therapy, and sometimes immunotherapy.

“Despite the treatment advances, recurrence risk depends largely on the tumour’s biology,” adds Dr. Prakash. “Women with triple-negative or HER2-positive breast cancer, or those with hereditary forms of the disease such as BRCA1 or BRCA2 mutations, face higher risks of recurrence.”

In Tahira’s Case

From publicly available information, Tahira Kashyap was initially diagnosed with a Stage 0, or pre-malignant, high-grade tumour and underwent a mastectomy. Recurrence in such early-stage cases is generally rare.

“However,” Dr. Prakash notes, “the high grade of the cancer cells may have played a role. High-grade cells tend to be more aggressive and may carry a greater potential for recurrence.”

How to Reduce the Risk of Recurrence

While recurrence can't always be entirely prevented, lifestyle changes and regular monitoring can significantly reduce the risk and boost long-term health outcomes. Dr. Prakash shares the following steps:

• Eat a Balanced Diet: Incorporate a variety of fruits, vegetables, whole grains, and legumes. A nutrient-dense diet supports immunity and overall well-being.
• Stay Physically Active: Engage in regular movement, such as walking, yoga, or swimming. Maintaining a healthy weight is crucial, as obesity is linked to higher recurrence rates.
• Manage Stress: Chronic stress can weaken the immune system. Techniques like meditation, deep breathing, and journaling can help manage mental and emotional health.
• Avoid Smoking and Alcohol: Both are known carcinogens and significantly increase the risk of recurrence. Eliminating these habits is essential for long-term health.
• Don’t Skip Follow-Ups: Regular follow-up appointments and screenings are vital. For the first five years post-treatment, active surveillance is key. After that, annual check-ups are still recommended.

Cancer recurrence is one of the toughest realities survivors may face. But knowledge, vigilance, and lifestyle choices can empower us to stay ahead. It’s about strengthening the body’s defences while continuing to stay positive and proactive.

Your health journey doesn't end with treatment—it's a lifelong partnership with your body. Take care of it, and it will take care of you.