Syringocystadenoma Papilliferum: A Case Series and Literature Review

Background: Syringocystadenoma papilliferum is an uncommon benign adnexal tumor originating from apocrine or eccrine sweat glands. It frequently occurs on the head and neck and is often associated with nevus sebaceous, posing diagnostic challenges in clinical practice due to its variable clinical presentations. Purpose: To investigate the clinical and histopathological characteristics and outcomes of five cases with syringocystadenoma papilliferum and to improve the clinical understanding of this disease in combination with the literature. Patients and Methods: The clinical and histopathological characteristics and outcomes of five Chinese patients with syringocystadenoma papilliferum were retrospectively analyzed. Results: There were two males and three females with an age at onset ranging from 0 to 69 years. All the skin lesions were located on the head and neck, with 4 cases occurring on the scalp and 1 case occurring on the neck. Clinical manifestations were isolated nodules, plaques, or linear, papillary plaques, with skin-colored to light yellowish, yellowish pink, or red. The skin lesions of all cases showed a slow increase with age. The histopathological findings were as follows: the papillary projections covered by double layers of epithelial cells and stroma rich in plasma cells. The pathologies of the two cases suggested syringocystadenoma papilliferum combined with nevus sebaceous. All cases underwent complete surgical excision treatment. Postoperative follow-up duration ranged from 24 to 48 months, with no recurrence observed in surviving cases. Conclusion: Syringocystadenoma papilliferum is a rare cutaneous appendageal tumor, which is easily confused with nevus sebaceous and verrucous lesions. It often occurs on the head and neck. In this small case series, two of five cases demonstrated coexisting syringocystadenoma papilliferum with nevus sebaceous, underscoring the recognized association between these entities. For nevus sebaceous lesions that have persisted for a long time or have undergone morphological changes, the possibility of secondary tumors such as syringocystadenoma papilliferum should be considered. Complete surgical resection with histopathological confirmation is recommended as the definitive management strategy, with postoperative follow-up to monitor for potential recurrence or development of secondary tumors, particularly in cases associated with nevus sebaceous. Keywords: syringocystadenoma papilliferum, nevus sebaceous, tumor, histopathology, treatment