This cross-sectional analysis examined online US crowdfunding campaigns from 2010–2018. Campaigns including prostate, breast, bladder, kidney, cervical, uterine, ovarian, testicular, oral, and thyroid cancers were included. Multivariable modeling was utilized to examine predictive factors for successful campaigns. A total of 1830 online cancer campaigns were included in the final analysis. Breast cancer was estimated to be the most frequent online campaign type (n = 3682), followed by cervical (n = 492), kidney (n = 475), ovarian (n = 460), and prostate cancers (n = 382). Breast cancer campaigns generated the most total funding ($15.3 million). In adjusted models, breast cancers generated significantly more donations per campaign than any other cancer. There was no difference in the average amount of funds raised per campaign by most cancer types, except for thyroid (19.4% less than breast, p < 0.001). Friend-authored campaigns generated more funding than self- and family-authored. Male cancers are under-represented, and breast cancer campaigns are disproportionately over-represented in online medical crowdfunding and generate more donations than many other cancers. Gendered differences in cancer crowdfunding are likely multifactorial and may be influenced by social networks and public health campaigns
