Bullous Pemphigoid-Associated Mortality Rate in a Canadian Tertiary Referral Centre.

BACKGROUND: Bullous pemphigoid (BP) is the most common autoimmune blistering disorder in adults. Most individuals with BP are over the age of 60. Its worldwide incidence has been increasing owing to population aging. Observational studies published over the last 2 decades highlight the non-negligible, albeit variable overall mortality of BP patients, with reported 12-month mortality rates of 10.8% to 40.8%, and 24-month mortality rates of 20.1% to 51.0%. Data in the Canadian population are lacking. OBJECTIVES: We aimed to estimate the 12- and 24-month overall mortality rate of Canadian patients diagnosed with BP, and to identify independent risk factors adversely impacting overall survival. METHODS: A retrospective cohort study of 166 patients with a diagnosis of BP between 2010 and 2020 was carried out at Centre hospitalier de l'Université de Montréal (CHUM), a tertiary referral center in Montréal, Québec, Canada. Cumulative mortality was calculated using the Kaplan-Meier estimator, and independent prognostic factors were identified using a Cox proportional hazards regression model. RESULTS: Eighty-five patients (51.2%) in our study were female. The median age was 79.1 years old, and 80 patients (48.2%) were 80 years old or older. Mortality at 12 and 24 months in our study cohort was 16.2% (CI95% = 10.5 - 21.8) and 27.6% (CI95% = 20.5 - 34.7), respectively. In a multivariate analysis, patients who were male, 80 years old or older, and/or had a diagnosis of a major neurocognitive disorder had a poorer overall survival. CONCLUSIONS: The all-cause mortality of patients with BP in our study population compared favorably with international data reported in the literature.

Basal cell carcinoma stroma as a mimicker of lymphatic invasion: A case report.

Basal cell carcinoma metastases are rare. We report a case of an 83 year-old male with recurrent cutaneous infiltrative basal cell carcinoma on the right vertex with tumor aggregates of infiltrative basal cell carcinoma in the lymphatic vessels of the superficial dermis strongly suspected on pathology slide evaluation during Mohs micrographic surgery. D2-40 immunohistochemical stain allows the detection of lymphatic invasion by highlighting endothelial cells. Further histologic review and D2-40 stains performed on the paraffin-embedded sections did not reveal an endothelial cell lining in favor of lymphatic invasion. What was identified as lymphatic invasion was the result of a peculiar basal cell carcinoma stroma. Correct identification of basal cell carcinoma stroma as a mimicker of lymphatic invasion would prevent potentially invasive investigation as well as associated costs. This is of great importance as the prognostic and therapeutic implications can be of significant value for the patient.