Superficial Basal Cell Carcinoma

This prospective, randomized, controlled, and single-blinded non-inferiority clinical trial compare the efficacy and tolerability of high intensity focused ultrasound (HIFU) to standard cryotherapy in the treatment of low-risk basal cell carcinomas (BCCs) and Bowen's disease (BD) in adults. The main questions it aims to answer are: * Is HIFU an efficient treatment option for BCCs and BD? * What medical problems do participants get after HIFU? Researchers will compare HIFU to standard cryotherapy with liquid nitrogen to see if the ultrasound works to treat these local and low-risk non-melanosytic skin cancers. Participants will: * Be treated either with HIFU (intervention) or cryotherapy (control). * Visit the clinic 4 weeks, 1-, 3- and 5 years after the treatment for check-ups, tests and survey questions.

The investigators will compare the application of two different creams for the treatment of low-risk skin cancers-superficial basal cell carcinoma (sBCC) and squamous cell carcinoma in situ (SCCis). 5-Fluorouracil cream is currently FDA approved for the treatment of superficial basal cell carcinoma and is routinely used by dermatologists across the country and at Boston Medical Center (BMC) for SCCis. The normal treatment regimen is 4 weeks of the 5-fluorouracil cream for both skin cancers. The application of a compounded cream consisting of 1:1 ratio 5-fluorouracil with calcipotriene will be tested. This combination cream has been shown to clear pre-skin cancers called actinic keratoses and prevent future skin cancers from developing. This combination cream for 7-14 days to see if this shorter treatment course provides clearance of the 2 types of skin cancer. This combination cream is successfully used in this manner to treat other subtypes of related skin cancers. This will be a pilot study with The primary endpoint for this pilot randomized single blinded clinical trial will be the response to treatment (yes versus no). The lesions will be assessed clinically for clearance of cancer, as would normally be done and is consistent with how comparable studies have assessed clearance. Participants will be followed closely afterwards for three years with visits at 6 months, which does not vary from standard practice. If the lesions are not clear of cancer or equivocal clinically, the lesions will be re-biopsied and normal standard of care procedure will take place.

This study will be a multicenter, prospective, open label, one-arm study intended to assess the Safety and Efficacy of EscharEx (EX-02) in the treatment of Basal Cell Carcinoma. In patients with one primary superficial or nodular basal cell carcinoma lesion with a diameter of 5-10mm (Histologically confirmed BCC) located on the trunk or upper extremities (not including the hands), with well-defined borders and no previous radiation therapy.