cancer

In 2024, some 2.3 million new cases of cancer worldwide were linked to infections — 12 per cent of all cases diagnosed that year — according to a study published in the journal The Lancet Oncology. Almost all of these cases are linked to five pathogens: the stomach bacterium Helicobacter pylori, the human papillomavirus (HPV), the hepatitis B and C viruses, and the Epstein-Barr virus. Low- and middle-income countries account for 77 per cent of all infection-related cancer cases.

A team of Spanish researchers has investigated the early stages of metastatic cells taking hold in target organs and has discovered that there is a transitional stage during which these ‘metastatic seeds’ are particularly vulnerable. They have also demonstrated in mice and in human samples that these micrometastases can be eliminated using three drugs, two of which are already approved for other indications. The study is published in the journal Cancer Cell.

A team led by the Silent Spring Institute (USA) drew up in 2024 a list of 921 chemicals that could increase the risk of developing breast cancer. They have now published an analysis of the presence of these compounds in everyday products in the United States. According to their findings, 485 are present in pesticides and as many as 462 in food, amongst other sources studied. Although the study does not allow for the estimation of risk or the establishment of causality, according to the authors, “transparency regarding how and where the population is exposed to these products will help to support public health research, exposure reduction and health protection regulations”. The study is published in Environmental Health Perspectives.

Infection with the bacterium Helicobacter pylori is a known risk factor for stomach cancer. Its link to colorectal cancer, however, remains an unconfirmed hypothesis. An international team has reviewed 43 studies on this subject and found that 22 per cent of colorectal cancer cases could potentially be linked to this infection, although when they selected the 14 most reliable studies, the figure fell to 12 per cent. According to the authors, exposure to Helicobacter pylori could be contributing significantly to the number of cases of colon cancer worldwide, but they point out that their study is only exploratory and that more robust research, such as clinical trials, is needed to establish a causal link. The results have been published in eGastroenterology.

Chemotherapy-induced peripheral neuropathy is a side effect of platinum-based cancer treatments that affects more than 60 per cent of patients and causes pain, a burning sensation and numbness. The psychedelic compound psilocybin could help prevent it, according to researchers behind a study using mouse models published in Science. Two doses of psilocybin administered prior to treatment prevented peripheral neuropathy for up to six cycles of chemotherapy without reducing its anti-tumour effects. The author of another perspective article on this study, also in Science, states that “the challenge now is to translate this understanding of the underlying mechanisms into carefully designed clinical trials”.

A team of researchers in South Korea has analysed the oral and faecal microbiomes of just over 507 volunteers and has concluded that, in patients with gastric and colorectal cancer, there is a greater transfer of microbes from the mouth to the gut. Furthermore, not only does this transfer differ between tumour types, but, according to their findings, an analysis based on oral samples is capable of detecting colorectal cancer with greater sensitivity than the standard faecal occult blood test. However, “before it can be used in practice, clinical trials would need to be carried out in real-world screening populations”, the authors explain. The study is published in the journal Cell Host & Microbe.

In a press release, the pharmaceutical companies Moderna and Merck have announced the results of their ongoing Phase 3 INTerpath-001 clinical trial, which is evaluating an mRNA vaccine (intismeran) in combination with pembrolizumab in patients with completely resected Stage IIB–IV melanoma. There is as yet no scientific publication containing data on improved survival or a reduction in recurrence.

Even though we know it is important to protect ourselves from the sun to reduce the risk of skin cancer, the incidence of melanoma is on the rise in Spain. Why? How common and dangerous is this form of cancer? How can it be treated? In this article, we address key questions about this disease, drawing on expert sources.

A study published in JAMA Network Open has examined whether the colorectal cancer screening programme based on faecal immunochemical testing, launched in the Basque Country, was associated with lower mortality from this cause over a 21-year period. The study — a retrospective, population-based cohort study — included all residents of the Basque Country (2.2 million people) between 2004 and 2024. The screening programme, aimed at people aged between 50 and 69, was launched in 2009. According to the study, screening was associated with a 50 per cent reduction in mortality from this cause among adults in that age group. Furthermore, a significant change in the trend was observed just three years after the programme began.

Since 2012, a population of brown catfish in a lake between Canada and the United States has been observed to have a very high incidence of melanoma, a tumor generally associated with sun exposure. Now, a team from Vermont (USA) has discovered that, in this case, it is a transmissible cancer that spreads from fish to fish like a parasite. This finding represents the fourth known transmissible cancer in the animal kingdom and the first in any species of fish or freshwater animal; previous examples include facial tumor disease in Tasmanian devils, a venereal tumor in dogs, and leukemia-like transmissible diseases in clams, mussels, and other bivalve mollusks. The researchers published their results in Nature and emphasize that the disease poses no known risk to humans.