Surgical resection of hepatic metastasis markedly improves survival among melanoma patients, according to new study findings published in the July issue of the Journal of the American College of Surgeons. These results challenge a current dogma in melanoma, as it is most often considered fatal once it has spread to the liver with a 4- to 6-month median overall survival.
In the past, surgical treatment for hepatic metastases was not considered an option for most patients as the disease typically spreads to other organs. However, advances in surgical techniques along with new systemic therapies have made existing therapies more effective and opened the door to new therapeutic approaches, according to study authors.
“Although there has been a great deal of excitement about the new medical therapies, which are clearly enormous advances, those are still not the answers for everyone,” said lead investigator Dr Mark Faries, Director of the Melanoma Research Program at John Wayne Cancer Institute in Santa Monica, California. “We’ve been proponents of metastasectomy for a long time and wanted to know how our patients who had been treated surgically for liver metastases had done.”
The Study Findings and Shortcomings
In this largest single centre study, the researchers calculated overall and disease-specific survivals from hepatic metastasis diagnosis. Potential prognostic factors included primary tumour type, depth, medical treatment response, location, and surgical approach.
For the study, Dr Faries and colleagues studied medical records of 1,078 patients who had been treated for melanoma hepatic metastases at their centre since 1991. Of those, 58 were treated surgically with hepatic resection. In some cases, surgical treatment included local ablation therapy in addition to resection.
Median overall survival among patients who underwent surgical resection was more than triple that of patients who received medical therapy without surgical treatment (24.8 months vs. 8 months). The five-year survival rate for surgical patients was 30%, compared with 6.6% for the non-surgical group.
“What we have seen in previous studies is that many patients who are able to undergo resection of their metastatic disease from melanoma can have good long-term outcomes, which is important to remember even in an era of more effective medications,” Dr Faries explained.
Median overall survival was similar among patients undergoing ablation (with or without resection) compared with those undergoing surgical treatment alone.
On multivariate analysis of surgical patients, completeness of surgical therapy and stabilisation of melanoma on therapy before surgery predicted overall survival.
In their article, the authors speculate that the advent of more effective systemic therapy in melanoma may substantially increase the fraction of patients who are eligible for surgical intervention, and this combination of treatment modalities should be considered whenever it is feasible in the context of a multidisciplinary team.
However, the study limitations include the fact that the investigation was a retrospective study spanning two decades, which means researchers were unable to control for certain factors. The number of patients is small and additionally, since isolated hepatic metastases are rare in melanoma, the vast majority of the metastatic melanoma population would not be candidates for surgical resection.
This study was supported by grant P01CA29605 from the USA National Cancer Institute, Dr Miriam & Sheldon G Adelson Medical Research Foundation (Boston), Borstein Family Foundation (Los Angeles), The California Oncology Research Institute (Los Angeles), and the John Wayne Cancer Institute Auxiliary (Santa Monica). Among the study co-authors, Dr Leung was the Harold McAlister Charitable Foundation Fellow (Los Angeles), and Dr Hari was the William Randolph Hearst Foundation Fellow (San Francisco).