Cellular myxoma is an uncommon type of myxoid benign tumor, predominantly occurring in adult female patients aged >40 years. This report aims to document a case of cellular myxoma that occurred in the buccal mucosa. Compared to intramuscular myxomas, cellular myxoma demonstrates hypercellularity and vascularity. Its manifestation in the soft tissue of the head and neck area is exceptionally rare. Generally, cellular myxoma manifests as a firm and immovable mass covered with normal oral mucosa, with no associated clinical symptoms. Homogenous low signal intensity on T1-weighted scans and high-signal intensity on T2-weighted magnetic resonance scans reveal cellular myxoma, as most lesions show well-defined margins and heterogeneous contrast enhancement. The significant histologic features include a focal or diffuse increase in cellularity with fibroblast-like cells and vascularity with an abundant collagenous matrix. Our presented case reflects these facts examinations, based on which a final diagnosis of cellular myxoma was made. Immunohistochemistry revealed locally and diffusely positive SMA and CD34. The clinical tendency of cellular myxoma with hypercellularity may affect the production of myxoid and collagenous substrates, and if complete resection is not performed, the possibility of local recurrence in the primarily affected region remains. Hence, complete surgical excision was performed under general anesthesia, and follow-up until a year after treatment revealed no observed recurrence. To achieve precise diagnosis and complete treatment without local recurrence, several diagnostic examinations should be considered.

Ⅰ. INTRODUCTION
Ⅱ. CASE REPORT
    Clinical examinations
    Radiological examinations
    Treatment
    Histopathological and immunohistochemicalfindings
Ⅲ. DISCUSSION
Ⅳ. CONCLUSION

• 구혜진(경희대학교 치과대학 구강악안면외과학 교실) | Hyejin Koo (Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyung Hee University Seoul, Republic of Korea)
• 정준호(경희대학교 치과대학 구강악안면외과학 교실) | Junho Jung (Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyung Hee University Seoul, Republic of Korea) Corresponding author
• 이현우(을지대학교 의과대학 의정부을지대학교병원 구강악안면외과) | Hyun-Woo Lee (Department of Oral and Maxillofacial Surgery, Uijeongbu Eulji Medical Center, Eulji University, Republic of Korea)
• 오주영(경희대학교 치과대학 구강악안면외과학 교실) | Joo Young Ohe (Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyung Hee University Seoul, Republic of Korea)
• 최병준(경희대학교 치과대학 구강악안면외과학 교실) | Byung-Joon Choi (Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyung Hee University Seoul, Republic of Korea)
• 황정혜(경희대학교 치과대학 구강악안면외과학 교실) | Junghye Hwang (Department of Oral and Maxillofacial Surgery, School of Dentistry, Kyung Hee University Seoul, Republic of Korea)