Radiographic imaging during initial nodal and metastatic status staging for patients with cutaneous melanoma may provide significant insight into incidental findings that need to be addressed, and might change treatment protocol, according to study data published in a Letter to the Editor in the Journal of the European Academy of Dermatology and Venereology.
The aim of this retrospective study was to analyze the rates, significance, and influencing factors of nonmelanoma-related, or incidental, findings on images procured during the initial staging of cutaneous melanoma. Imaging modalities included positron emission tomography scans, computed tomography scans, chest radiographs, or brain magnetic resonance imaging scans. Radiographic images were obtained from the University of Iowa Hospitals and Clinics between January 2000 and December 2013.
The study included 115 patients. Of the images included in the study, 5% of the scans indicated melanoma findings only. Melanoma and incidental findings were identified in 24% of the scans, and incidental-only findings were identified in 58% of the scans. In 16% of the cases, upstaging occurred as a result of a not-suspected, significant, melanoma-related finding. Of the incidental findings, 40% required further medical action, with lung and liver lesions the most common findings.
On analysis, a trend toward increased incidental findings with increasing age was observed. A pathologic stage III melanoma significantly increased the likelihood of an image finding (odds ratio, 3.21; 95% CI, 1.19-8.67; P =.02) and increased the chance of a melanoma and incidental finding (odds ratio, 6.81; 95% CI, 1.88-24.69; P =.01). Patients with scans that did not indicate findings had a decreased risk for a melanoma-related death (hazard ratio, 0.11; 95% CI, 0.02-0.48; P <.001), and patients with scans that indicated only incidental findings had a worse survival rate when compared with patients with scans indicating melanoma and incidental findings (hazard ratio, 0.56; 95% CI, 0.3-1.05; P =.07).
Limitations of this study included the retrospective nature, the relatively small sample size, and the lack of power for some statistical analyses.
The researchers concluded that “pathologic stage was found to be a statistical predictor of increased risk for having an imaging finding, which correlated significantly with increased mortality … [and that] beyond direct impact on melanoma staging, imaging investigation may reveal significant comorbidities in patients with cancer.”
Stump M, Keller J, Mott SL, Stolmeier D, Milhem M, Liu V. The prevalence and significance of radiographic incidental findings during initial staging of melanoma: a retrospective study [letter; published online August 30, 2019]. J Eur Acad Dermatol Venereol. doi:10.1111/jdv.15912