Do 50% of individuals with a history of BCC will develop another one within 5 years of diagnosis regardless of the age of the individual?

The 2010 study {1} reviewed a few existing studies and seems to lean toward age as not having an impact on the recurrence rate (however, note that 1 of the reviewed studies does indicate youth+female as a risk factor of recurrence after Mohs surgery):

(NMSC = non-melanoma skin cancer, e.g. basal cell carcinoma (BCC))

Young Age Is Not a Clinical Risk Factor Although young age (typically < 40 years) is generally viewed as a clinical risk factor for aggressive NMSC behavior, after much deliberation the panel decided it is not. The published biomedical literature does not strongly support “young age,” per se, as a risk factor. Leffell et al.{46} documented an increased percentage of basal cell cancer with aggressive histologic growth patterns in young persons, but this histologic feature is already a separate risk factor in the algorithm

When the features of 54 basal cell cancers in young patients referred for Mohs surgery were compared with similar tumors in older patients,{47} tumor location, histology, and clinical morphology did not differ appreciably between the groups. In fact, initial lesion and final defect sizes were statistically smaller in the younger group. In a study from the United Kingdom in which 39 young patients with basal cell cancer were followed up for a minimum of 5 years,{48} 4 tumors were incompletely excised, 2 recurred, and 1 metastasized. Another study observed a higher number of recurrent tumors in younger women referred for Mohs surgery than in other demographic groups.{49} Finally, 2 more recent studies found no difference in either recurrence rates or presence of aggressive histologic subtypes in younger versus older patients with basal cell skin cancer.{50,51}

The panel decided that, taken together, these studies do not support the suggestion that young age alone is a high-risk factor for NMSC behavior. Any tumor showing an aggressive histologic growth pattern, regardless of patient age, becomes a high-risk tumor.

References:

• {1} Miller SJ, Alam M, Andersen J, et al. Basal cell and squamous cell skin cancers. J Natl Compr Canc Netw 2010; 8:836. https://jnccn.org/view/journals/jnccn/8/8/article-p836.xml; DOI: https://doi.org/10.6004/jnccn.2010.0062
• {46} Leffell DJ, Headington JT, Wong DS, Swanson NA. Aggressivegrowth basal cell carcinoma in young adults. Arch Dermatol 1991;127:1663–1667.
• {47} Dinehart SM, Dodge R, Stanley WE, et al. Basal cell carcinoma treated with Mohs surgery. A comparison of 54 younger patients with 1050 older patients. J Dermatol Surg Oncol 1992;18:560–566.
• {48} Cox NH. Basal cell carcinoma in young adults. Br J Dermatol 1992;127:26–29.
• {49} Robins P, Albom MJ. Recurrent basal cell carcinomas in young women. J Dermatol Surg 1975;1:49–51.
• {50} Milroy CJ, Horlock N, Wilson GD, Sanders R. Aggressive basal cell carcinoma in young patients: fact or fiction? Br J Plast Surg 2000;53:393–396.
• {51} Roudier-Pujol C, Auperin A, Nguyen T, et al. Basal cell carcinoma in young adults: not more aggressive than in older patients. Dermatology 1999;199:119–123.