New methods for determining melanoma prognosis

This study examined the prognostic value of S100B and lactate dehydrogenase in non-resectable metastatic melanoma.

Melanoma that has metastasized, or spread to other areas of the body, has a poor prognosis. While 5-year survival rates can be as high as 41% in patients whose cancers are resectable, or able to be surgically removed, these rates are much lower among patients with non-resectable tumors. In addition, estimating prognosis among non-resectable patients is significantly more difficult, as non-surgical treatments such as chemotherapy and immunotherapy show variable response rates. Lactate dehydrogenase, or LDH, levels have previously been identified as a reliable prognostic indicator among metastatic melanoma patients due to the correlation between LDH and the extent of metastatic processes. LDH levels are elevated when cells and tissues are damaged, and particularly elevated during active tumor metastasis into various internal organs.

S100B (a small protein) levels are also elevated during cell damage. S100B has been previously shown to be useful in determining prognosis for metastatic melanoma patients with resectable tumors. However, it is unclear whether S100B can be helpful in predicting the prognosis of patients with non-resectable tumors. The analysis explored whether S100B levels could predict survival among non-resectable metastatic melanoma patients.

This study followed 499 patients with non-resectable melanoma over 27 months. Data collected on each patient included the site and type of original melanoma, the sites of metastases, LDH and S100B levels, and the type of treatments received.

Overall, 1-year survival rates were 40% and 5-year survival rates were 6.2%. Metastasis to one or more internal organ was seen in 66% of patients, with nearly 22% of those to the brain. Patients without brain metastasis were twice as likely to survive beyond 1 year. LDH was elevated in 40% of patients. LDH elevation was found to double the mortality risk compared to patients holding normal LDH levels.

69.2% of patients noted elevated S100B levels, which was associated with a 60% increase in the risk of mortality compared to patients without S100B elevation. Normal S100B levels was significantly associated with long-term survival, with 12.3% of patients with normal S100B levels surviving beyond 5 years.

This study concluded that S100B was an accurate prognostic indicator for long-term survival in patients with non-resectable metastatic melanoma.