Cholesterol Clefts in Basal Cell Carcinoma: An Under-Recognized Association.

Cholesterol clefts have rarely been described in cutaneous tumors other than lipid-rich tumors. However, they seem to be a relatively common phenomenon in basal cell carcinoma (BCC). This study was undertaken to determine the frequency of cholesterol cleft deposition in BCCs, and to identify associated histopathologic and clinical features. Twenty-eight of 249 BCC cases reviewed showed features of cholesterol cleft. Mean disease duration in those with cholesterol cleft was significantly longer than in those without cholesterol cleft (5.58 vs. 3.29 years, respectively; P = 0.013). Sex and age distributions, and average tumor longest diameter (11.6 vs. 9.41 mm) were no different for those with or without cholesterol clefts. The most common anatomical location was the nose in both those with and without cholesterol clefts. BCCs without cholesterol clefts more frequently involved the periauricular and perioral areas, and areas other than the head and neck, such as the trunk and lower extremities (P = 0.087). Histopathologic features of necrosis (26/28, 92.86%), keratinization (19/28, 67.86%), and pigment deposition (18/28, 64.29%) were found to be associated with cholesterol clefts. Cholesterol clefts were intratumorally located in 27/28 cases (96.43%), and stromally located in 2 cases (7.14%); intravascularly located cholesterol clefts were observed in no case. In conclusion, this study shows that cholesterol clefts are relatively common in BCC, and suggests that cholesterol crystal deposition could be associated with longer disease duration and microtrauma.