World Health Day: Exploring the factors behind the rise in cancer rates among younger adults

Cancer is the leading cause of death worldwide, accounting for nearly 10 million deaths in 2020 according to the World Health Organization (WHO). India ranks among the highest contributors of cancer patients in Asia. A 2024 study published in The Lancet Regional Health Southeast Asia journal reveals that India registered nearly 12 lakh new cancer cases and 9.3 lakh deaths in 2019, the second highest in Asia.

While there are multiple causes that attribute to the multi-stage development of tumour cells, the incidence of cancer rises dramatically with age, most likely due to a build-up of risks for specific cancers that increase with age. However, the recent announcement of 42-year-old Kate Middleton is an unfortunate reflection of the rising incidence of cancer among people under 50. A study published in the British Medical Journal about early-onset cancers across the world for the period of 1990-2019 showed a surprising 79.1 per cent increase since 1990.

India with its young demographic is also experiencing the same trend, as per Dr. Amit Rauthan, head of department and consultant of medical oncology, haematology, and haemato-oncology at Manipal Hospital. "We know that cancers increase with age as ageing leads to cell abnormalities which predispose to cancer development. But in recent years, the trend has been changing. There has been a steady rise in cancers in India, and in the last few years, we have seen a significant rise in cancers in the younger population. The rising incidence of cancers of the breast, colon, stomach, oesophagus, lung, and ovary are being observed among younger adults, with many patients being younger than 40 years," explains Rauthan. Ahead of World Health Day, the oncology expert delves into the different aspects of early onset cancer.

What are the probable causes of early onset cancer?
Rauthan: The cause of an increase in cancers in the younger age is multifactorial, but the exact cause is not known. This could be attributed to changes in lifestyle with the increase in smoking and alcohol intake, increase in consumption of western fast-food processed diet, increased obesity, and sedentary lifestyles. The environment around us could be contributory to increased air and water pollution, and the diet we eat could be affected by pesticide usage. Also, there could be a background of genetic changes leading to the development of hereditary cancers in the young.

Why is there a delay in detection of early onset cancers?
Rauthan: Many cancers in the young are caught in the late stages because the symptoms get neglected as there is a misconception that cancers usually occur in older age. Many youngsters think they are very healthy and active so they cannot develop cancer, and do not get themselves tested even if they have suspicious symptoms. This is especially seen in gastrointestinal cancers like colon cancer, where blood in stool gets ignored for a long time leading to late detection. Suspicious breast lumps get ignored many times leading to late detection of breast cancer.

How can early onset cancer differ from the rest?
Rauthan: Some of the younger age cancers have a more aggressive behaviour, than their older counterparts. We see this in breast cancer, where we see the aggressive triple negative type of breast cancer more commonly than the slower growing hormone positive breast cancer, which are more common in the older age groups. Triple negative breast cancer needs to be treated more aggressively with chemotherapy than the hormone positive breast cancer, which does well with hormonal tablets. Lung cancer seen in younger patients is more molecular driver driven and is different from the older age lung cancer. Ovarian cancer seen in younger ages may have a hereditary impact and this has an implication in terms of treatment and survival. The overall cure rates and survival of younger age cancers is good in the early stage as these patients are fit to tolerate most of the curative therapies.

Which tests can be done for early detection of cancer?
Rauthan: Cancer when detected and treated in the early stages has a very good cure rate in both the younger and older age groups. The best way to beat cancer is to try to catch it early. Early suspicious signs like a lump or abnormal swelling in the body, abnormal bleeding, significant weight loss, abnormal changes in the bowel habit, persistent unexplained cough, change in warts should all be evaluated by a cancer specialist. Mammography for breast cancer, HPV testing or PAP smear for cervical cancer, stool examination and colonoscopy for colon cancers, PSA testing for prostate cancer are utilised as screening strategies which help in early detection. There are significant advances in cancer treatment in the form of immunotherapy, targeted therapies, biological therapies and precision oncology. All of these are now becoming a part of treatment of younger age cancer patients, leading to improved success.

Can family medical history play a role in detection?
Rauthan: There is a segment of young onset cancers which have a hereditary background in which there is a distinct history of multiple cancers in the family. This is especially seen in younger females with breast and ovarian cancer who have a breast cancer (BRCA) germline mutation. BRCA mutations can even affect men who may develop prostate, pancreatic and rarely male breast cancer. Genetic or hereditary testing has become a norm in patients with breast and ovarian cancer as this has a significant implication for treatment, early detection and prevention of cancers in patients and family members who carry the mutated gene abnormality.

Another example is young onset colon and uterine cancers in people who have a mutated mismatch repair gene, leading to a syndrome called Lynch syndrome. Lynch syndrome is a familial cancer syndrome in which affected members can develop various cancers like colon, uterine, small intestine and ureter cancer in the younger age. They usually do very well and can be cured by surgery if detected at an early age. In the late stages, immunotherapy has a very important role in treatment. There are many technological advances which have improved testing for these hereditary cancer genes by simple blood tests.

Based on your experience, and observation, what are some of the psychological concerns of a young cancer patient?
Rauthan: There are many psychological barriers that we need to overcome in their treatment. Apart from thoughts of long-term survival and cure, there is also a worry about the side effects of treatment. The implication of chemotherapy side effects like hair fall, vomiting, skin discolouration, loss of appetite, change of taste, and fatigue are worrisome as they have to carry on daily work too. Surgery of the breast is worrisome for many young women, and its implications on body image are a concern. There are also worries about sexual health and fertility. Many females are concerned about whether treatment would impact their future pregnancy. This can also have a significant impact on their interpersonal relationships. All these potential impacts need to be kept in mind while dealing with young age cancer patients.

How is cancer treatment evolving to better serve younger patients?
Rauthan: A lot of advances and comprehensive cancer treatment are being structured around young cancer patients. While planning breast cancer treatment, emphasis is given to breast conservation surgery, and preserving the breast has a positive psychological impact on these young patients. Treatment of rectal cancer is based on starting with chemotherapy and radiotherapy, and then planning surgery, with the maximum attempt of preserving normal rectal function. Organ-preserving surgeries are being done to preserve the quality of life. In the early stages of head and neck cancers, de-escalation of treatment is being followed in certain patients to enable a cure with reduced side effects. Precise radiotherapy techniques using stereotactic radiotherapy in being utilised to enable better cures and lesser side effects to normal organs. In lung cancer, emphasis is given to molecular testing as young lung cancer patients have many driver abnormalities, which may be treated with oral targeted therapies, with good success.

Chemotherapy is being done using chemoports and portable pumps so that patients do not need to stay in the hospital for the same and can continue to carry on their daily work schedule. Hair fall during chemotherapy is being reduced in certain situations by using scalp cooling devices. Sperm cryopreservation and embryo or oocyte preservation techniques are being offered before starting chemotherapy to preserve fertility in young cancer patients. Supportive measures with advanced anti-vomiting medications and growth factors are used with chemotherapy to minimise side effects and enable patients to continue their work during their treatment. Emphasis is to be given to psycho-oncology counselling services as well they can be a huge help in coping with the stress of diagnosis and treatment for patients.