Nurse warns of six little-known signs of 'silent' kidney cancer surging in under-50s

A nurse at Kidney Cancer UK has urged people to watch for six often-missed symptoms of kidney cancer, warning that the disease is being diagnosed increasingly in adults under 50 and is frequently discovered only by accident.

Hazel Jackson told the Daily Mail that kidney cancer is "often called a 'silent disease' because many people don't notice anything wrong," and that early detection substantially improves outcomes. "If spotted early, three-quarters of patients survive at least five years," she said, but once the cancer has spread "survival drops to just 18 percent."

Jackson highlighted six symptoms she said people commonly mistake for minor conditions: recurring urinary tract infections, a dull ache or pain in the side or lower back, persistent unexplained tiredness, rapid unintended weight loss (cachexia), a lump or swelling in the side or abdomen, and any blood in the urine. She said the symptoms do not always appear together and can be vague, which contributes to late diagnoses.

"The first symptom people often overlook is recurring urinary tract infections (UTIs)," Jackson said. "While a single infection is usually easy to treat, repeated UTIs can signal a deeper problem. They can feel like burning when peeing, a constant urge to go, cloudy or strong-smelling urine, and sometimes back discomfort or fever." She added that recurring infections can seriously affect daily life and, though most are harmless, repeated infections can mask serious kidney problems, including cancer.

Jackson described how blood in the urine is often the most significant red flag. "It can show in different ways — from obvious deep red or brown urine to a faint pink tinge, tiny specks, or even blood only at the end of urination," she said. "Some people assume a small drop isn't worth worrying about, but in essence, any blood in your urine is abnormal and should be checked immediately. It could be caused by something simple like a kidney stone or infection, but it can also be an early sign of kidney cancer. Never dismiss it."

Public health data show the number of kidney cancer cases is increasing in both the United Kingdom and the United States, particularly among younger adults. Nearly 14,000 people are diagnosed with kidney cancer each year in Britain, with about 4,700 deaths annually; the United States records roughly 80,000 new cases a year. Research cited by Kidney Cancer UK indicates that people born in 1990 are up to three times more likely to develop kidney cancer than those born in the 1950s, a trend experts attribute in part to rising levels of obesity and high blood pressure.

A report published by Kidney Cancer UK earlier this year found that almost all cases were detected incidentally — for example, during scans for unrelated conditions or in emergency departments. Only about one in five patients surveyed said their disease was identified after a GP ordered relevant tests. The charity's findings underscore concerns that vague or intermittent symptoms may not prompt immediate investigation in primary care.

Risk factors for kidney cancer include smoking, obesity, high blood pressure, chronic kidney disease and a family history of the disease. Medical literature notes that cachexia, or wasting syndrome, is more commonly associated with advanced cancer; while patients with early-stage disease do not typically develop cachexia, up to four in five people with advanced cancer experience some degree of muscle and fat loss driven by inflammation and the tumour's metabolic demands.

Jackson advised people who notice persistent symptoms to seek medical advice and to be persistent if access to tests or referrals is delayed. "Trust your instincts," she said. "If you notice blood in your urine, ongoing pain, or repeated infections, see your GP and push for checks. Be persistent, clearly explain your symptoms, ask for your concerns to be taken seriously, and consider requesting a referral to a specialist if needed."

Clinicians say earlier diagnosis improves treatment options. When kidney cancers are identified at an early stage, patients are more likely to be eligible for surgery and other interventions that can extend survival. When cancers are discovered late, after they have spread, treatment aims more often at symptom control and prolonging life rather than cure.

Health services and charities continue to urge greater awareness of renal cancer symptoms among the public and professionals, and to call for timely diagnostic pathways in primary care so that suspicious signs are investigated without undue delay.