New Delhi: Kidney cancer, also known as renal cell carcinoma (RCC), is a malignant tumour that originates in the kidneys, two bean-shaped organs located on either side of the spine in the upper back. The kidneys play a crucial role in filtering waste products and excess fluids from the blood, converting them into urine that is expelled from the body through the urinary tract. The kidneys also play a critical role in blood pressure control, vitamin D metabolism, and red blood cell production. When abnormal cells in the kidney begin to grow uncontrollably, they can form a tumour that may impair kidney function and spread to other parts of the body if not detected early.

In an interaction with News9Live, Dr. Paul Russo, MD, FACS, Urologic Surgeon, Memorial Sloan Kettering Cancer Centre, New York, US, explained how smoking and high blood pressure can affect the kidney cancer death rate.

Smoking: A Direct and Indirect Killer

Smoking significantly elevates the risk and worsens outcomes of RCC. As per the study, both current and former smokers had 1.5–1.6 times higher odds of presenting with advanced-stage RCC, such as metastatic disease or lymph node involvement, compared to never-smokers.

Mechanistically, toxic carcinogens found in tobacco, such as nitrosamines and polycyclic aromatic hydrocarbons, enter the bloodstream, concentrate in renal tissue, and can inflict direct DNA damage over years of exposure. This contributes to tumour initiation and promotes tumour aggressiveness through chronic inflammation and oxidative stress. Epidemiological data further reveal that smoking accounts for approximately 25–30% of RCC cases, with male smokers facing up to double the cancer risk versus non-smokers. Smoking cessation my decrease the risk of Kidney Cancer going forward.

Hypertension: The Silent Aggravator

Hypertension, or high blood pressure, affects nearly 1 in 3 adults globally and is increasingly recognized as both a risk factor for kidney cancer and a determinant of poorer outcomes. Long-standing hypertension causes chronic damage to renal blood vessels, glomeruli, and tubules, leading to a cascade of inflammatory and fibrotic changes in the kidney tissue. This chronic damage creates an environment ripe for carcinogenesis. Hypertension is believed to confer an increased risk of kidney cancer of 1.4 to 1.7 fold over normotensive people.

Hypertension also complicates treatment. Surgical options like nephrectomy and partial nephrectomy carry higher perioperative risks in hypertensive patients, including increased bleeding and cardiovascular complications. Furthermore, certain targeted therapies for kidney cancer can exacerbate hypertension, forcing oncologists to reduce doses or interrupt treatment, which can negatively impact cancer control

The Deadly Duo: Smoking and Hypertension Together

When smoking and hypertension co-exist, as they frequently do, their impact on kidney cancer mortality becomes even more pronounced. Both risk factors are independent and additive and both can affect men and women. These two factors often amplify each other’s harmful effects on the kidneys. Smoking promotes endothelial dysfunction and atherosclerosis, which worsen blood pressure control. Conversely, hypertension exacerbates renal injury from the toxins found in tobacco smoke. Together, they create a vicious cycle of renal insult, DNA damage, and systemic inflammation.

Kidney cancer mortality is not solely dictated by tumour biology or treatment access. Modifiable risk factors like smoking, hypertension, and obesity can play a pivotal role in determining patient outcomes. Addressing these factors through proactive prevention, early diagnosis, and comprehensive care can significantly reduce kidney cancer deaths and improve long-term survival for patients worldwide.