Disease Description

Squamous cell carcinoma (SCC) is an uncontrolled growth of abnormal cells arising in the squamous cells. Squamous cells are cells which compose most of the skin’s upper layers . SCCs often look like scaly red patches, open sores, elevated growths with a central depression, or warts; they may crust or bleed. SCC is mainly caused by cumulative UV exposure over the course of a lifetime. It can become disfiguring and sometimes deadly if allowed to grow. [1]

Prevalance

An estimated 700,000 cases of SCC are diagnosed each year in the US, and about two percent of all SCC – up to 8,800 people – died from the disease in the US in 2012. [1]

Current Treatment Options

For superficial low-risk Squamous Cell Carcinoma lesions treatment options include surgical excision, or topical treatment with topical 5-fluorouracil or imiquimod. Squamous cell carcinomas usually remain confined to the epidermis (the top skin layer) for some time. However, the larger these tumors grow, the more extensive the treatment needed. They eventually penetrate the underlying tissues, which can lead to major disfigurement, sometimes even the loss of a nose, eye or ear. A small percentage — estimates run from 2 to almost 10 percent - spread (metastasize) to distant tissues and organs. When this happens, squamous cell carcinomas frequently can be life-threatening. [1]

Evidence for and Proposed Mechanism for Cannabinoid Therapies

Accumulating recent evidence implicates the endocannabinoid system in the regulation of growth of skin cells. Casanova et al. have demonstrated that various human skin tumors (e.g. basal cell carcinoma, squamous cell carcinoma) express cannabinoid receptors both CB1 and CB2. Local administration of synthetic CB1 and CB2 agonists induced growth inhibition of malignant skin tumors in mice. This growth inhibition was accompanied by enhanced intra-tumor cell death and impaired tumor vascularization (altered blood vessel morphology, decreased expression of pro-angiogenic factors such as VEGF, placental growth factor and angiopoietin 2) [2]

1. Skin Cancer Foundation. www.skincancer.org/

2. Pacher, P. et al. The endocannabinoid system of the skin in health and disease: novel perspectives and therapeutic opportunities. Trends Pharmacol Sci. Aug 2009; 30(8): 411–420.