The role of confocal microscopy in recurrent cutaneous angiosarcoma

Dear Editor, Angiosarcoma is a rare tumor of endothelial cell-origin that comprises about 1% of all soft tissue sarcomas. It has a similar distribution between sexes but is more common in elderly Caucasian men. It can occur in any body organ, but the head and neck are the most frequently involved, with the scalp and face being the most commonly affected regions.1 Angiosarcoma is mostly a spontaneous tumor; however, a transformation from a benign vascular lesion has been reported previously.2 It can be radiation induced, it can occur in the setting of chronic lymphedema (Steward–Treves syndrome) or it can be associated with familial syndromes such as neurofibromatosis, BRCA1 and BRCA2 gene mutations and exposure to chemicals such as vinyl chloride, arsenic, and radium. Cutaneous angiosarcoma can appear insidiously as a lesion resembling a bruise. A nodular component can develop with progression of the tumor.1 It can become ulcerated and is usually associated with tissue infiltration. Its typically multifocal. Spreading to the lungs, bones, brain, lymph nodes, and other soft tissues can occur through blood circulation. The prognosis is poor, with a 5-year survival of 10%–30%, and the recurrence rate is high, especially in the head and neck region.1 Surgical resection with wide margins and radiotherapy with or without chemotherapy are definitive treatment options. Although surgery appears to be associated with better overall survival,3 some patients receive definitive radiotherapy/chemotherapy without surgery due to unresectable lesions or refusal of surgery.4 Early recognition and detection are critical to patient outcomes. This can be aided by new diagnostic tools such as confocal microscopy. An 86-year-old male was referred to our clinic with a history of scalp angiosarcoma. The patient had undergone multiple surgeries with skin graft reconstruction due to several incomplete excisions of the tumor 2 years earlier, followed by the onset of a new lesion compatible with angiosarcoma 1 year later, requiring further surgical excision and skin grafting. Three months after the last procedure, during a routine follow-up visit, we noticed the presence of a violaceous area localized in the area of the collision of the two grafts (Figure 1a). The lesion was initially documented by videodermoscopy, which showed a reddish bluish background with non-arborizing irregular vessels and a pinkish periphery with fine telangiectasias (Figure 1b). The lesion was re-evaluated after 1 month. As no changes were observed, confocal microscopy was performed. The main elements we found were rosette-like cells grouped in clusters, dilated horizontal vessels, and scattered small hyper-reflecting cells (Figure 2). A diagnosis of angiosarcoma recurrence was suggested. A biopsy followed by a histopathological examination confirmed the suspected diagnosis. Cutaneous angiosarcoma is both a diagnostic challenge and a difficult disease to manage. Often presenting insidiously as a bruise-like lesion or a purplish papule that may be mistaken for a benign lesion, it has a high rate of recurrence, as in our case, and a propensity for early metastasis.5 Prompt diagnosis is therefore needed. Dermoscopy is certainly helpful in suspicious cases. There are a few reports in the literature describing, as in our case, the presence of the classic colors of vascular lesions as a main and constant feature: shades of red, purple, and blue with a variable presence of visible vascular structures.6 However, no pathognomonic pattern has yet been described. Confocal microscopy could represent an additional useful diagnostic tool. Although the use of confocal microscopy has already been described in a case of breast angiosarcoma,7 we report the first case of scalp angiosarcoma evaluated using this technique. The elements we observed with confocal microscopy are similar to those described by Perrot et al.,7 namely the presence of neovascularization with horizontal vessels and small bright inflammatory cells. We also described rosette-like cells grouped in clusters. Unlike the French group, we did not observe the presence of fibrous septa. Although further reports are certainly needed to better describe the aspects of cutaneous angiosarcoma and for confocal microscopy to be considered an effective diagnostic method, the use and knowledge of this diagnostic tool could help in the early diagnosis of the disease and therefore in its best management. Open access funding provided by BIBLIOSAN. The authors declare they have no conflicts of interest. The work reported in this publication was funded by the Italian Ministry of Health (RC-2023-2778942). All patients in this manuscript have given written informed consent for participation in the study and the use of their de-identified, anonymized, aggregated data, and their case details (including photographs) for publication. Data sharing is not applicable to this article, as no new data were created or analyzed in this study.