Histologic changes in a patient with CPLX and ESRD. Breast biopsy (benign) from a non-diabetic 60-year-old Caucasian female with an irregular breast mass 12 months prior to the development of clinical abdominal CPLX (multiple tumorous calcifications in the abdominal adipose tissue and skin ulceration). These tissue sections demonstrate the underlying systemic VOC of calciphylaxis. Her ulcerated area on the abdomen was not biopsied due to a possibility of aggravating tissue healing. Panel a: Demonstrates the H&E basophilic staining of intimal VOC in a small musculoelastic artery. Panel b: Demonstrates the medial fluorescent-like staining (due to inverted coloration of H & E basophilic staining) of VOC in an arteriole. Note the adjacent venule medial VOC staining. Venular VOC – thrombosis has not been as extensively studied as the arteriole and one must consider the possibility that VOC – thrombosis in the post-capillary venule may be important as the increased capillary edema and pressure may result in capillary endothelial dysfunction and promote an additive factor in the important role of subcutaneous ischemia and skin necrosis and ulceration. Note the panarteriolar involvement of the intima, media, and adventitia in the various vessels. Panel c: Demonstrates the H & E basophilic adventitial staining of VOC in an arteriole.