MOHS Patients Can Reliably Estimate Preoperative Non-Melanoma Skin Cancer Size

As the presurgical size and anatomic location of non-melanoma skin cancer correlates to the complexity of Mohs micrographic surgery (MMS), patients are frequently asked to self-report their preoperative tumor size to aid in efficient scheduling and triage. We aimed to assess the accuracy of patient's self-reported lesion measurements prior to MMS by comparing patient's estimates of lesion size to the measurements taken by a Mohs surgeon. We conducted a retrospective chart review of 1,000 patients who underwent MMS and self-reported their lesion size at a preoperative telehealth visit. The patients reported their lesion size in one dimension (1D)/two dimensions (2D) or using a pencil eraser as a size reference. Patients demonstrated excellent reliability (intra-class correlation coefficient [ICC]: 0.916) while reporting their lesion size in two dimensions, and moderate reliability (ICC: 0.644) while reporting their lesion size in one dimension. Patients had slight agreement (κ = 0.178) with the surgeon's preoperative measurement while using a pencil eraser as a size reference. Dermatology practices must be encouraged to utilize telehealth to obtain presurgical size estimates from patients using 1D or 2D size measurements. By utilizing presurgical size estimates, surgeons can better triage and schedule patients to provide appropriate anticipatory guidance to patients and their caretakers.