A new study in the Journal of Investigative Dermatology led by Dr. Delphine J. Lee suggests that the bacterial community inside melanoma tumors, also known as the intratumoral microbiome, may play a role in the progression of the disease.
What the Researchers Found
Melanoma is rare, making up only about 1% of all skin cancers, but deadly, with statistics giving an average of one death from melanoma per hour in the United States. Dr. Lee’s team measured the bacterial DNA in melanoma tumors and noticed some interesting patterns:
- Bacterial diversity and outcomes: Tumors with a broader variety of bacteria were sometimes associated with shorter survival and an earlier recurrence of the cancer.
- Certain bacteria appeared to be associated with better outcomes: Types typically found on healthy skin, such as Cutibacterium and Corynebacterium, were more frequently present in patients with favorable outcomes.
- Other bacteria appeared to be associated with worse outcomes: Bacteria like Streptococcus and Porphyromonas were more common when the disease came back sooner.
Not All Melanomas Act the Same
For melanomas that develop in the nose and mouth, bacteria present weren’t associated with similar outcome patterns. This suggests the relationship between bacteria and melanoma may depend on where the tumor grows.
What It Could Mean
This research doesn’t prove that bacteria cause changes in melanoma, but it does suggest a possible connection worth further study. Understanding how bacteria and tumors interact might one day help doctors better predict how melanoma will behave or even inspire new ways to treat it.