A Rare Case of Low-Grade Dedifferentiated Liposarcoma Presenting as a Pharyngeal Polyp: Avoiding a Pitfall With Significant Repercussions.

Dedifferentiated liposarcoma is a nonlipogenic sarcoma of variable histological grade that frequently arises in association with a well-differentiated liposarcoma. Dedifferentiation occurs in approximately 10% of well-differentiated liposarcomas and is most commonly encountered in the retroperitoneum. Dedifferentiated liposarcoma of the upper respiratory tract is an extremely rare occurrence. Herein, we report a very rare case of low-grade dedifferentiated liposarcoma of the pharynx that presented as a polyp mimicking a benign process clinically and microscopically. We discuss the relevant molecular findings and review the current literature.

Plexiform (multinodular) schwannoma of soft palate. Report of a case.

Plexiform schwannoma is a rare benign neoplasm of the neural sheath characterized by a multinodular plexiform growth pattern. Only 5% of schwannomas have a plexiform or multinodular growth pattern. Schwannoma apparently derives from the Schwann cells. Extracranially, 25% of all schwannomas are located in the head and neck region, but only 1% show an intraoral origin. The intraoral lesions show a predilection for the tongue, followed by the palate, buccal mucosa, lip and gingival. Microscopic examination is necessary to confirm the diagnosis. Characteristic histological signs are the palisading of the spindle-shaped Schwann cells around the central acellular area, so called Verocay bodies. We report a case of a 21-year-old woman with a smooth mass of the soft palate that was gradually increasing. Surgical excision of the mass was done and the histopathology and immunohistochemistry study of the excised lesion revealed a multinodular plexiform schwannoma of the soft palate. The patient is under regular clinical control, with no signs of recurrence after 17 months. Plexiform schwannomas of the soft palate are mentioned very rarely in the English literature. This rare benign tumor is worthy of recognition because it can be misdiagnosed as plexiform neurofibroma.

Papillary thyroid microcarcinoma: clinicopathological characteristics and implications for treatment in 276 patients.

BACKGROUND: There is debate concerning the clinical significance of papillary thyroid microcarcinoma (PTMC), and therefore, the rise in the incidence of PTMC creates management dilemmas. The purpose of this study was to analyse the clinicopathological characteristics of PTMC in an island region that has a high prevalence of goitre and to determine risk factors for the worst prognosis. MATERIALS AND METHODS: Data from 1874 patients who underwent a total thyroidectomy between January 2002 and December 2008 were reviewed retrospectively. A total of 276 patients who were diagnosed with PTMC in a final pathology report were included in the study. A PTMC was defined as a papillary thyroid carcinoma with a diameter ≤ 10 mm. Clinicopathological features were evaluated by both univariate and multivariate analyses. RESULTS: Of the 276 patients with PTMC, 219 patients (79·3%) were incidentally diagnosed. Two hundred and two patients had carcinomas of ≤ 5 mm, and 74 patients presented with carcinomas that ranged in size from 0·6 to 1·0 cm. Lymph node metastasis was diagnosed in 3·5% of patients with tumours ≤ 5 mm, and 21·6% of patients presented tumours > 5 mm. Upon multivariate analysis, clinically suspected diagnosis, a tumour size > 5 mm and an age over 45 years at diagnosis were independent risk factors for capsule invasion, while tumour multifocality, bilaterality, size of tumour > 5 mm and thyroid capsule invasion were independent risk factors for lymph node metastasis at diagnosis. CONCLUSIONS: Patients presenting multifocal, bilateral PTMC with a maximum diameter > 5 mm and thyroid capsule invasion may have an increased risk of lymph node metastasis. These factors should be considered in the follow-up for these patients.