[Clinical characteristics, diagnosis and treatment of nasal cartilage mesenchymal hamartoma in infants].

Objective: To explore the clinical characteristics, pathological features, and diagnosis and treatment strategies of nasal chondromesenchymal hamartoma (NCMH) in infants and young children. Methods: A retrospective analysis was conducted on seven cases of NCMH infants and young children admitted to Beijing Children's Hospital, Capital Medical University from April 2015 to January 2022. The cohort included 5 males and 2 females, aged from 6 days to 2 years and 3 months. General information, clinical symptoms, imaging findings, treatment plans, postoperative complications, recurrence and follow-up time were collected, summarized and analyzed. Additionally, immunohistochemical characteristics of the lesion were examined. Results: The clinical symptoms of 7 children included nasal congestion, runny nose, open mouth breathing, snoring during sleep, difficulty feeding, and strabismus. All patients underwent electronic nasopharyngoscopy examination, with 5 cases of tumors located in the right nasal cavity and 2 cases in the left nasal cavity. No case of bilateral nasal cavity disease was found. All 7 patients underwent complete imaging examinations, with 5 patients underwent MRI and CT examinations, 1 patient underwent CT examination only, and 1 patient underwent MRI examination only. The CT results showed that all tumors were broad-based, with uneven density, multiple calcifications and bone remodeling, and some exhibited multiple cystic components. The MRI results showed that the tumor showed low signal on T1 weighted imaging and high or slightly high signal on T2 weighted imaging. All patients were diagnosed through histopathological examination and immunohistochemistry, including 7 cases of Ki-67 and SMA (+), 5 cases of S-100 and Vimentin (+), and all EMA and GFAP were negative. All patients underwent endoscopic resection surgery through the nasal approach, with 3 cases using navigation technology. Five cases of tumors were completely removed, and two cases of tumors were mostly removed. No nasal packing was performed after surgery, and no postoperative nasal, ocular, or intracranial complication occurred in all patients. Follow up assessments conducted 6 to 84 months post-surgery revealed no instances of tumor recurrence in any of the patients. Conclusions: The clinical symptoms of children with NCHM mainly depend on the size and location of the tumor. Nasal endoscopic surgery is the main treatment method. In cases where critical structures like the skull base or orbit are implicated, staged surgical interventions may be warranted. Long-term follow-up is strongly advised to monitor for any potential recurrence or complications.