van Winden MEC, Hetterschijt CRM, Bronkhorst EM, et al. - In this cohort analysis of patients with basal cell carcinoma (BCC), watchful waiting (WW) was a suitable approach in several patients, particularly those with asymptomatic nodular or superficial BCCs and a limited life expectancy. Patients should be followed up on a frequent basis to see if a WW approach is still appropriate and if patients still choose WW, as well as to reconsider the effects of therapy and refraining from treatment.

• With a median (interquartile range [IQR]) follow-up of 9 (4-15) months, 280 BCCs were chosen for WW in 89 patients (47 men [53%] and 42 women [47%]).

• The included patients ranged in age from 73 to 88 years old.

• Patient-related factors or preferences (ie, prioritizations of comorbidities, severe frailty, or limited life expectancy) were grounds for initiating WW in 74 (83%) patients, followed by tumor-related factors (n = 49; 55%).

• For 35% and 46% of the patients, treatment-related and circumstantial reasons were important.

• The minority of tumors grew in size (47%).

• Tumor growth was linked to BCC subtype but not to initial tumor size or location.

• The estimated tumor diameter increase in 1 year was 4.46 mm for BCCs with at least an infiltrative/micronodular component and 1.06 mm for the remaining BCCs (only nodular/superficial component/clinical diagnosis).

• Tumor burden or potential tumor burden, resolved reason(s) for WW, and reevaluation of patient-related factors were the most common reasons for starting therapy.