Changpei Lu,1,2,* Rongshuang Zhang,1,* Lingbo Bi,2 Ting Luo,1 Wenbing Lai,1 Weixin Fan,2 Haixia Jing1 

1Department of Dermatology, Taihe Hospital, Hubei University of Medicine, Shiyan, People’s Republic of China; 2Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Weixin Fan, Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, People’s Republic of China, Email hairmanfwx@163.com Haixia Jing, Department of Dermatology, Taihe Hospital, Hubei University of Medicine, Shiyan, 442000, People’s Republic of China, Email jinghaixia1210@163.com

Purpose: To conduct a retrospective review and analysis of clinical data on pilomatricoma over the past 9 years, with a focus on clinical characteristics, Diagnostic Challenges, and Therapeutic Outcomes.
Patients and Methods: We performed a retrospective study on patients diagnosed with pilomatricoma at our department from 2013 to 2022. Data collected from hospital and outpatient records, as well as pathological reports, included patient age, sex, onset, clinical and histopathological features, preoperative diagnosis, treatment methods, recurrence, and outcomes.
Results: A total of 105 patients were included. The primary clinical manifestation was a slowly growing subcutaneous mass. The median age at excision was 14 years, with the youngest patient being 8 months old and the oldest 71 years old. Head and neck tumors accounted for 67.6% (n=71) of cases, followed by the upper limbs (20.9%, n=22), with other sites including the back and lower limbs. The male-to-female ratio was 1:1.6. Tumor diameter ranged from 0.4 to 5.0 cm, with a mean of 1.0 cm. Only one case exhibited recurrence. Differential diagnoses included epidermoid cyst, sebaceous cyst, and fibroma, among others. The characteristic histopathological features were eosinophilic ghost cells and basophilic basal-like cells arranged in irregular strands or clusters. The preoperative diagnosis was consistent with the pathological diagnosis in only 28 cases (26.7%). The optimal treatment approach is complete surgical excision, with a low recurrence rate of 1.0%. No cases of malignant transformation were observed.
Conclusion: Pilomatricoma is a benign tumor with atypical morphology, often leading to misdiagnosis. Careful histopathological examination is crucial, and early excision demonstrates significant effectiveness in preventing recurrence.

Keywords: calcified epithelioma, pilomatricoma, benign tumor, clinical analysis, pathology