UC San Diego

Importance

Cutaneous pyogenic granulomas (PGs) are commonly encountered, benign, vascular tumors, in which epidemiologic factors have been variably reported, in part, due to sample size limitations and a focus on either adult or pediatric patients.

Objective

To assemble a large dataset of pathologically diagnosed PGs across the continuum of age and investigate patterns of PGs by demographic factors, including age, sex, and anatomical location.

Design, setting, and participants

This retrospective case series included case reports of patients with pathologically confirmed PGs of cutaneous origin reported between April 1, 2010, to March 31, 2020. The pathology database at a large tertiary academic center in the Midwestern US was queried for case reports that included the term pyogenic granuloma or lobular capillary hemangioma. Individuals were included in the analytic sample if they had a pathologically confirmed diagnosis of a PG. PG cases were excluded if they included PG only as a part of the pathological differential diagnoses; were recurrent; or were of noncutaneous origin. These data were analyzed between March 2022 and March 2023.

Main outcomes and measures

The main outcomes were sex biases in frequency overall, by anatomical region, and by left-right laterality using exact binomial tests. Additional outcomes included differences in age-by-sex distribution overall and by anatomical region using Kolmogorov-Smirnov tests.

Results

Of 1009 unique pathologically confirmed PG records from 987 individuals, 376 individuals (38.1%) were younger than 18 years, of whom 122 (32.4%) were female. A total of 611 individuals were 18 years and older, of whom 364 (59.6%) were female. Overall, PGs between male and female individuals were equally distributed for all anatomical locations except lower extremities, in which females were more frequently affected. The distribution of PGs by age was significantly different between male and female individuals, with this difference primarily associated with the head/neck and trunk but not with upper extremity or lower extremity anatomical locations. Neither left-right laterality bias among upper extremity PGs nor anterior-posterior bias among truncal PGs was observed.

Conclusions and relevance

In this retrospective case series, an age-by-sex interaction was found in the incidence of PGs, with PGs on the head/neck and trunk being more common in males younger than 20 years and in females 20 to 50 years of age. These findings suggest that trauma may not be a major etiologic factor for PGs. Future studies are necessary to confirm this and to understand the causes of the age-by-sex interaction.