Q&A: 10 cancer-related misconceptions

As China marks 30th "National Anti-Cancer Week" from April 15-21, learn from health experts about cancer-related misconceptions.

Q: Are there any dietary or nutritional supplements that have special anti-cancer effects?

A: Experts believe there's no scientific evidence to support any health care product or supplement as a "specific medicine" for cancer prevention. While certain products may be beneficial to the health or helpful in the nutritional management of cancer patients, they are definitely not substitutes for standard cancer treatments such as surgery, chemotherapy, targeted radiotherapy, or immunotherapy.

Patients and their families should follow the doctors' guidance instead of blindly believing the representations in the advertisements of health products.

Q: Does staying up late contribute to liver cancer?

A: There is no relevant scientific research to prove that staying up late will cause liver cancer. Common risk factors for suffering from the cancer include hepatitis virus infection, liver cirrhosis, alcoholism, gene mutation, hereditary metabolic disease, smoking, obesity, etc, and the causes have not been fully found.

Staying up late may lead to disruption of the human circadian rhythm, thus affecting the body's immunity and metabolic capacity and weakening the immune system. This would have a certain impact on liver function, and may increase the risk of suffering from liver cancer, but it does not mean that staying up late will definitely contribute to cancer. Everyone should develop good living habits and those who have liver disease should actively seek treatment.

Q: Does strengthening nutrition make tumors grow faster?

A: Experts believe there is no scientific basis for believing that cancer patients need to deliberately restrict their nutritional intake. Instead, a reasonable nutritional supplement is of great benefit for cancer patients, who often have problems such as weakness, loss of appetite, and emaciation caused by the damage during anti-tumor treatment. It can help improve the body's immunity and reduce the side effects of anti-cancer treatment, thus not only providing the necessary nutrients for the body but also inhibiting tumor growth. Cancer patients are recommended to increase their intake of high-quality protein and unsaturated fatty acids appropriately and eat more fresh fruits and vegetables.

Q: Cancer patients can't do a biopsy of malignant tumors?

A: A needle biopsy is crucial in enabling doctors to assess the nature of a tumor, which is essential for making treatment decisions and serves as a necessary diagnostic foundation prior to chemotherapy and radiotherapy. The current paracentesis procedure does not pose a risk of tumor metastasis, as the puncture needle is designed in a manner similar to that of a ballpoint pen. It retrieves tumor tissue with the pen refill, retracts it into the pen holder, and exits the body together, effectively preventing the leakage of malignant cells. Even if a small number of tumor cells are extracted through the puncture needle, they will be eradicated by the immune system at any time, thus preventing tumor metastasis.

Q: Does drinking coffee cause cancer, as acrylamide was detected in 59 types of coffee?

A: Although coffee contains acrylamide, it does not significantly increase the risk of cancer when consumed in normal amounts. The formation of acrylamide in coffee occurs during the coffee-making process, and this compound is also produced in food at cooking temperatures above 120°C. Hence, acrylamide can be found in other foods such as potato chips and bread. To promote health and longevity, it is recommended that individuals reduce their consumption of fried and baked foods, opting instead for steamed, stewed, or boiled methods of food preparation.

Q: Does eating over-boiled eggs with a 'black layer' cause cancer?

A: The formation of the "black layer" of eggs is just a chemical process during cooking. It is non-toxic and will not cause cancer. During the long heating process, the amino acids in the protein will be decomposed to produce sulfide, while the egg yolk is rich in iron. Through the interaction between the sulfide and the iron element, ferrous sulfide is formed, which makes the original golden yolk into a bluish gray or even black green.

Q: People shouldn't color hair because hair dye is carcinogenic?

A: Hair dye contains "p-phenylenediamine", a chemical substance that may pose a certain risk of cancer only with frequent and excessive exposure. There is no established evidence that qualified hair dye and moderate hair coloring would increase cancer incidence. However, other components in the hair dye, such as hydrogen peroxide, dyes, coupling agents, and certain botanical ingredients, can stimulate the scalp and cause allergies. Frequent hair coloring is also harmful to the hair. Therefore, individuals are advised to buy the hair dye of a qualified brand and do allergy tests before hair coloring, and the hair dyeing interval is best controlled at about 4 months.

Q: Cancer is incurable and the treatment is meaningless?

A: With the continuous advancement of medical technology, the therapeutic effect of many cancers has been significantly improved. Even some cancers can be completely cured or effectively controlled if detected early. Furthermore, with early detection and timely intervention, symptoms of some cancers can be alleviated and the patients' quality of life can be improved. People with cancer should build up confidence and embrace a better life with the help of modern medical treatment.

Q: Are there always obvious symptoms in the cancers of urinary system?

A: Cancers in different parts of the urinary system, including the kidneys, ureters, bladder, prostate (in men) and other tissues, may show a variety of symptoms that are not always readily apparent. Symptoms may vary greatly depending on the type and stage of cancer. For example, kidney cancer may have no obvious symptoms in the early stage, whereas painless hematuria is the most common symptom of bladder cancer, for which some patients may overlook seeking timely treatment as they mistakenly regarded their symptoms as a common urinary system inflammation. Kidney cancer and prostate cancer are usually asymptomatic in the early stage. More than half of the patients with symptoms are already in late metastasis or even in late stage, making it challenging to detect and diagnose these cancers in a timely manner.

Q: Do patients carrying hepatitis B virus get liver cancer?

A: For patients infected with hepatitis B virus, their symptoms appear to be acute or chronic. Acute hepatitis B is typically the result of a first-time infection with the virus, although currently, most cases are due to acute attacks by the hepatitis B virus. The majority of patients with acute hepatitis B can be cured, but a small number may progress to chronic hepatitis B. For patients who are carriers of the hepatitis B virus and have no significant liver changes, the risk of developing liver cancer is relatively low. In cases of chronic hepatitis B that has not progressed to liver fibrosis or cirrhosis, the likelihood of developing cancer is also low. However, if it progresses to cirrhosis, there is a significantly increased risk of developing liver cancer. Therefore, while not all carriers of the hepatitis B virus will develop liver cancer, this population still has a higher incidence rate and should pay special attention during physical examinations.