Responding to melanoma’s growing threat
Melanoma’s burden is increasing and the rising rates cannot simply be attributed to increased disease detection, according to a research letter published last month in JAMA Dermatology.
Dermatology researchers, who reported on U.S. melanoma incidence in 2009, updated melanoma incidence and mortality trends with 2016 numbers. They referred to American Cancer Society estimates of the number of new cancer cases and deaths expected in the U.S. in the current year. Data on cancer incidence, mortality and survival came from the National Cancer Institute, Centers for Disease Control and Prevention and the North American Association of Central Cancer Registries and mortality data from the National Center for Health Statistics, according to the 2009 paper.
Among their findings:
In 2016, an estimated 76,380 Americans will be diagnosed with invasive melanoma.
An American’s lifetime risk of developing invasive melanoma in 2016 is one in 54, whereas, reported risk in 2009 was one in 58.
In situ melanoma incidence is increasing at a faster rate. The lifetime risk of developing in situ melanoma went from one in 78 in 2009 to one in 58 in the current year.
Incidence of thin invasive tumors is increasing at a faster rate than thicker tumors. But the number of thicker tumors continues to increase, which is impacting the death rate from melanoma.
Also on the rise, five-year survival rates from melanoma.
The lifetime risk of being diagnosed with invasive or in situ melanoma is one in 28.
The estimated number of deaths from melanoma among Americans was 8650 in 2009, versus 10,130 in 2016.
The 2016 data suggests that invasive melanoma incidence in the U.S. is increasing on a lesser trajectory since 2009 than the death rate, which could mean that the effect of earlier detection on melanoma mortality has yet to be seen, the authors write.
While the data sheds new light on melanoma burden in the U.S., it also leaves many unanswered questions, according to Brian Gastman, M.D., plastic surgeon and medical and surgical director of melanoma at Cleveland Clinic. For example, it’s unclear if the data reflects overall survival or melanoma-specific survival. In the case of overall survival, which is what Surveillance, Epidemiology, and End Results (SEER) and National Cancer Database (NCDB) use, the number could include deaths from other causes, Dr. Gastman says.
“We know that the population of melanoma diagnoses continues to rise in the elderly, and the rate of death increase could be in part due to people who are at higher risk than the national average of dying from another cause,” says Dr. Gastman, who is not an author of the research letter.
Questions remain about the impact of continually improving surgical algorithms showing the importance of sentinel node biopsies and more on survival, as well as response rates seen with new targeted and immunotherapeutic drugs. Studies done in the last seven years have shown that a patient’s socioeconomic status and age, as well as the treatment institution’s location and type (academic versus community), could affect how a melanoma patient is treated, he says.
“The data could also imply that despite responses from therapies and improved short-term overall survival from best surgical practices, long-term results are not being impacted,” Dr. Gastman says.
As for the dramatic rise in the risk of in situ melanoma, Dr. Gastman says that, in part, the age of the nation is increasing and the number of new melanomas is increasing mostly in the elderly. There also are known increases among young women, which may present an opportunity for prevention because these patients’ diagnoses are likely due to environmental causes that could be altered and genetic causes that could be screened for, he says.
The research letter’s authors write that incidence rates could be higher than shown because melanoma is not a reportable disease in many states, and hospital tumor registries might not reflect all tumors biopsied and excised in the outpatient setting.
Given the data and potentially increasing rates of melanoma, the public needs to have access to timely care, Dr. Gastman says.
“Next, we need to make sure that we are working within practice algorithms that have been shown to improve overall survival,” Dr. Gastman says. “There are still some not using sentinel node biopsy often enough, or are using antiquated techniques for these node surgeries, or are not working with dermatopathologists who can make the diagnosis of even single cell metastases.”
Other examples of suboptimal care include surgeons operating on the head and neck, while not being comfortable with the anatomy, or non-surgical oncologists recommending a wide local excision only (possibly with inadequate margins), never giving the patient the opportunity to discuss options with those who treat the full surgical gamut of the disease, according to Dr. Gastman.
“Follow-up is also important as these patients cannot only recur, but also get second and third melanomas,” he says.
Disclosure: Dr. Gastman reports no relevant disclosures.