Using logistic regressions, the investigators estimated the effects of immunosuppression on poor outcomes. The researchers stratified these effects based on the number of SCC tumors and adjusted for tumor stage using criteria established by Brigham and Women’s Hospital, Boston, Massachusetts, and the American Joint Committee on Cancer, 8th edition (AJCC-8).
The proportion of patients with multiple tumors was higher in the immunosuppressed group than in the control group; of all the immunosuppressed patients, 57% (60 of 106) had multiple tumors, compared with 25% (53 of 212) in the immunocompetent group. Moreover, about 12% of the immunosuppressed patients (13 of 106) had 10 or more tumors, while no immunocompetent patient had 10 or more tumors.
Among the immunosuppressed people, those with 2 or more tumors had a higher risk of local recurrence compared with those with a single tumor. This risk equaled 30% among individuals with 2 tumors to 9 tumors and 69% among those with 10 or more tumors, compared with 4% among those with a single tumor, the researchers found. Similarly, the risk of any disease-specific poor outcome among the immunosuppressed patients was 9% in those with a single tumor, compared with 32% in those with 2 to 9 tumors, and 69% with 10 or more tumors. The researchers did not see significant increases in the risk of poor outcomes in the immunocompetent group.
Among these patients (with 2-9 tumors), the unadjusted odds of experiencing local recurrence or any disease-specific poor outcome were 10 times to 11 times higher for the immunosuppressed patients, compared with the immunocompetent ones. When adjusted for all staging criteria, these odds were between 11 times to 13 times higher among the immunosuppressed patients compared with immunocompetent individuals.
The findings underscore the importance of careful screening and aggressive treatment in immunosuppressed patients, the authors noted. Michele Green, MD, a dermatologist at Lenox Hill Hospital in New York City, who was not involved in the study, agreed with this conclusion. “Immunosuppressed patients need to be screened more often for skin cancer and treated more aggressively to ensure a better outcome,” she said. “This subset of patients is very vulnerable to poor outcomes and need[s] to be monitored closely.”
- Gonzalez JL, Reddy ND, Cunningham K., Silverman R, Madan E, Nguyen BM. Multiple cutaneous squamous cell carcinoma in immunosuppressed vs immunocompetent patients [published online March 13, 2019]. JAMA Dermatol. doi: 10.1001/jamadermatol.2018.5595