Basal Cell Carcinoma

EPIDEMIOLOGY

Race/Ethnicity

Risk of keratinocyte carcinomas, of which BCC is the most common (SCC being the other), is geometrically if not exponentially higher in fairer skin types. In fact, only 2.4% of ~785,000 medicare beneficiaries who had skin cancer were non-white. 97.6% of keratinocyte carcinomas in the medicare population are in non-hispanic white patients. (38019561)
This difference in risk is even more stark when comparing white and black patients: white patients have nearly 70x the risk of black patients and nearly 2.5x the risk of non-white/black individuals. Whites have 90x the risk of BCC compared to blacks and 63x the risk of SCC. (38019561)

Genetics

SUFU Pathogenic Variants

"Patients with germline SUFU PVs may present with multiple indolent basaloid neoplasms in addition to conventional basal cell carcinomas, typically appearing in the fourth to sixth decades of life." (39292485)

METASTASIS

Groover M, Gupta N, Granger E, et al. Patterns of metastasis from a multicenter cohort of metastatic basal cell carcinoma. J Am Acad Dermatol. 2024. PMID: 38331097.

BCC metastasis is extremely rare, estimated at 0.0028% (this is ~1 in 33,000, which is probably still a gross overestimate).
It happens in the setting of very large tumors (mean size of primary tumor was over 7cm).
41.5% were limited to regional lymph nodes.
30.2% were distant mets with LN involvement (usually diagnosed concurrently).
28.3% were distant mets without lymph node involvement.
Over 90% of distant mets were to lung, and over a third of distant mets were to bone (7 cases had both lung and bone mets).

TREATMENT

Imiquimod Cream Preceded by Superficial Curettage vs Surgical Excision for Nodular Basal Cell Carcinoma: A Secondary Analysis of a Randomized Clinical Trial. JAMA Dermatol. 2025. PMID: 39878970.

Protocol: Curettage included superficial removal of elevated tumor tissue, stopping at the level of adjacent normal skin followed by Imiquimod 5% cream 1 week after curettage self-applied once daily, 5 days per week, for 6 weeks (total of 30 applications).
Efficacy: At 5 years, surgical excision (SE) had a significantly higher tumor-free survival rate (98.2%) than superficial curettage (SC) followed by imiquimod cream (77.8%). Most treatment failures occurred within the first year.
Cosmetic Outcomes: SC plus imiquimod had better physician-rated cosmetic outcomes than SE. Patient-rated satisfaction and willingness to repeat treatment were similar between groups.
Conclusion: SC plus imiquimod is notably less effective long-term than surgery but may be reasonable to consider in patients averse to surgery who favor the cosmesis of SC plus imiquimod.