Supplementary Material for: Are iPARP safe in paraneoplastic dermatomyositis due to high grade serous carcinoma of the ovary? A case report and a review of the literature

Dermatomyositis is a chronic autoimmune disorder characterized by non-infectious inflammation of the muscles and skin, frequently associated with vasculopathy. This rare disease affects 1 to 5 per 100,000 individuals and manifests in varying degrees of severity [1]. While juvenile dermatomyositis affects children, adult cases are more common in women. The primary symptoms include muscle weakness, especially in the thighs and hips, and unique skin features such as rashes, heliotropic erythema, and Gottron's sign. Nail involvement, indicated by redness around the nails, is also possible. A significant aspect of dermatomyositis is its correlation with cancer, particularly as a paraneoplastic syndrome, which constitutes about 30% of cases [2]. There is a notable association with specific cancers, such as lung cancer in men and breast or ovarian cancer in women. Ovarian cancer is particularly linked, accounting for 13.3%-21.4% of dermatomyositis cases in women. Considering the link between paraneoplastic syndromes and cancer, it is important to explore whether treating the underlying cancer can influence the progression of these syndromes. Poly (ADP-ribose) polymerase (PARP) inhibitors, now a key component in ovarian cancer treatment due to their significant antitumor effects, have shown potential immunomodulatory properties that may impact paraneoplastic syndromes like dermatomyositis. This article investigates the relationship between PARP inhibitors and paraneoplastic dermatomyositis in ovarian cancer, highlighting the underlying mechanisms and therapeutic implications.