Novel use of Rose Bengal (PV‐10) in two cases of refractory scalp sarcoma

We report a novel intralesional (IL) treatment using Rose Bengal (RB) in two patients with refractory scalp sarcoma. Non-clinical studies in multiple melanoma lines have shown that RB causes selective necrosis upon preferential uptake into cancer cells. Clinical studies have demonstrated the utility of IL RB for cutaneous metastatic melanoma. Thompson et al. reported an objective response in 12 of 26 melanoma lesions, with 7 lesions remaining static over 12 weeks of observation. Foote et al. reported an increased response in melanoma lesions treated with radiotherapy following IL RB in three patients. The first patient is a 55-year-old man who underwent a complete resection of a metastatic scalp leiomyosarcoma and adjuvant radiotherapy. Four weeks later, seven new nodules were noted within the irradiated field. He was offered IL RB at a dose of 0.5 mL ¥ Lesion Volume. Nine lesions were injected with 0.6 mL of RB. All lesions demonstrated necrosis and subsequent healing by secondary intent, with complete clinical response after 5 months. The second patient is a 72-year-old man who underwent excision multifocal malignant fibrous histiocytoma (giant cell type) of the occipital scalp with perineural spread, followed by radiotherapy for recurrence in a left sub-occipital node. Four months later, he developed a new 2-cm scalp lesion and 0.9 mL of RB was injected into the lesion (Fig. 1.1) with good response (Fig. 1.2–1.4). He represented at day 63 with further local recurrence and was re-treated with RB with good clinical effect (Fig. 1.5). He subsequently developed pulmonary metastases and is undergoing systemic chemotherapy. RB was obtained under the Category A: Special Access Scheme of the Therapeutic Goods Administration, Australia, upon approval of the Royal Adelaide Hospital’s Drug Committee. Given the promising initial results of these two cases and demonstrated success in cutaneous metastatic melanoma, we recommend formal clinical study in refractory sarcoma.