Abstract
INTRODUCTION AND IMPORTANCE: Preoperative diagnosis of well-differentiated liposarcoma (WDLS) in the retropharyngeal space is challenging because of the difficulty in obtaining a biopsy tissue specimen that will yield the microscopic findings necessary for a definitive pathological diagnosis. This report describes a case of retropharyngeal WDLS that was successfully diagnosed intraoperatively, which allowed radical resection. CASE PRESENTATION: The patient was a 60-year-old man suspected of having a lipomatous tumor in the retropharyngeal space. On imaging, the tumor contained linear septum-like structures that were prominent behind the larynx. Pathological examination was performed using fine-needle aspiration cytology and core needle biopsy specimens. However, no malignant features were found. Given that partial biopsy of the retropharyngeal tumor by puncture was anatomically limited, we decided to collect appropriate tissue specimens for intraoperative pathological examination. During the operation, we biopsied the tumor, including the hard portion behind the larynx, anticipating inclusion of the septum-like structures seen on imaging. A pathological diagnosis of WDLS was successfully made and the tumor was completely excised. CLINICAL DISCUSSION: The fibrous septum with induration is important for intraoperative diagnosis of WDLS. The fibrous septum within the tumor was palpable as a rubbery hard portion. CONCLUSION: WDLS in the retropharyngeal space could be successfully resected surgically by making a rapid intraoperative pathological diagnosis using appropriately selected tissue sampled from a hard portion of the tumor.