Sensitive, sonic hedgehog (Shh) pathway-driven BCC epithelium arises through the ability to recruit and instruct TREM2 + VCAM1+ myeloid cells into a self-propagating phenotype that allows mutual proliferation and tumor growth with a dearth of effector lymphocytes present in the local environment16. The gene discussed is VCAM1; the disease is skin basal cell carcinoma.