Calendula
The flowers from Calendula (Calendula officinalis) have been used medicinally since the 12th century throughout Europe, predominately as an ingredient in topical preparations for the treatment of minor wounds, skin infections, sunburn, burns, eczema and dermatitis.
Results from preclinical and animal studies have identified several anti‑cancer activities from Calendula extracts including; antioxidant, anti‑inflammatory, induction of apoptosis (cell death), and cancer cell growth inhibition. (Arora et al, 2013; Matic et al, 2013; Jimenez-Medina et al; Prethi et al, 2006)
Although research into the anti-cancer potential of Calendula is limited to preclinical studies, its effects in the prevention of radiation-induced dermatitis have been established through clinical trials. Researchers completed a phase III randomised trial comparing the effectiveness of a Calendula preparation and trolamine (a topical salicylate pain reliever) for the prevention of acute dermatitis during irradiation for breast cancer. The study involved 254 post-operative breast cancer patients who began topical application with their allocated ointment on irradiated skin at the onset of radiotherapy, twice daily and continued until the completion of radiotherapy. The Calendula ointment was significantly superior to trolamine for the prevention of skin toxicity; 41% of patients using the Calendula ointment experienced acute toxicity compared to 63% from the trolamine group. Important to note too, that patients using the Calendula ointment had less frequent interruption of their radiotherapy due to skin toxicity.