Poor penile hygiene may increase the risk of penile cancer, particularly among uncircumcised men, Consultant Urologist Dr Duncan Kimani has warned.
Speaking during a Radio Generation interview on Monday, Dr Kimani said failure to clean beneath the foreskin can lead to the accumulation of smegma and chronic inflammation, conditions that may contribute to the development of penile cancer.
“Remember, when men don't really clean the foreskin properly, there is something called phlegm that builds up. So that phlegm is actually what triggers a chronic inflammatory state,” Dr Kimani said.
He explained that men with a foreskin should pay particular attention to genital hygiene, explaining that the larger surface area created by the foreskin can allow substances to accumulate when proper cleaning is neglected.
“The surface area is larger. The phlegm itself is also an inflammatory issue, so if you don't clean the penis properly, you are now predisposed to that,” he said.
Penile cancer is relatively rare globally, but it remains a significant health concern in some parts of Africa, Asia, and South America.
The International Agency for Research on Cancer (IARC), through its Global Cancer Observatory, estimates that 37,700 new cases of penile cancer were recorded globally in 2022, with 13,738 deaths from the disease.
The global age-standardised incidence rate was 0.79 cases per 100,000 people, while the mortality rate stood at 0.28 deaths per 100,000.
Africa accounted for 2,081 cases, representing about 5.5 percent of global cases, and 894 deaths, or 6.5 percent of global penile cancer deaths, according to the same dataset.
Asia recorded the highest number of cases, with 21,531, accounting for 57.1 percent of the global total.
Dr Kimani said circumcision has been associated with a protective effect against penile cancer, citing populations where boys are circumcised at an early age.
“A study was done on the patients who develop penile cancer, and it was noted that there was a protective effect, especially amongst the Jews who circumcise their children very early, so it was noted that because of that they had very low incidences of penile cancer.”
Medical evidence also identifies chronic inflammation and phimosis - a condition in which the foreskin is difficult to retract- as risk factors for penile cancer.
The American Cancer Society says phimosis can make it difficult to clean beneath the foreskin, potentially resulting in chronic irritation and inflammation.
The organisation recommends good genital hygiene for men with a foreskin, including retracting it and cleaning the entire penis where this can be done safely.
Historical IARC data have also documented substantial differences in penile cancer rates between populations and linked some of those differences to circumcision and genital cleansing practices. Earlier studies in Africa found higher rates in some populations where circumcision was uncommon, although the evidence does not mean that lack of circumcision alone causes cancer.
Dr Kimani also linked HIV infection to increased rates of penile cancer.
“HIV infections also kind of bring high rate of penile cancer,” he said.
The American Cancer Society similarly lists HIV infection among recognised risk factors for penile cancer, noting that the increased risk may be related to weakened immunity as well as the higher likelihood of other risk factors, including HPV infection.
Human papillomavirus is another important risk factor. Certain high-risk HPV types have been linked to penile cancer, with persistent infection playing a role in the development of some cancers.
Penile cancer can often be noticed early because most cases begin in the skin of the penis. However, the American Cancer Society says cancers developing beneath the foreskin may be harder to detect, particularly among men with phimosis.
Dr Kimani's comments therefore highlight genital hygiene as a practical preventive measure, particularly for uncircumcised men.
While circumcision may offer some protection, maintaining proper hygiene remains important because poor cleaning can allow the accumulation of substances beneath the foreskin and contribute to chronic inflammation.
Penile cancer remains uncommon compared with many other cancers, but the global figures show that it causes tens of thousands of new cases and thousands of deaths each year. Early attention to persistent changes, proper genital hygiene and timely medical assessment can help reduce avoidable risks and improve the chances of detecting the disease early.