Intranodal palisaded myofibroblastoma in the submandibular gland region: a case report

Abstract

Intranodal palisaded myofibroblastoma (IPM) is a rare benign tumor of the lymph nodes, particularly in inguinal lymph nodes. IPM originating from the submandibular gland lymph nodes is rarely encountered in clinical practice. Herein, we report the case of a 31-year-old male patient with IPM of the submandibular gland region and describe in detail magnetic resonance imaging findings and pathology. Magnetic resonance imaging detected a heterogeneous lesion with a hypointense rim on T2-weighted imaging with specificity in the left submandibular gland region. This case report will contribute to the accumulation of experience in the diagnosis of this disease.

Keywords: case report; intranodal palisaded myofibroblastoma; lymph node; magnetic resonance imaging; pathology; submandibular gland.

Figure 1

Coronal T1WI scan (A) showed the tumor mass on the upper pole of the left submandibular gland (blue arow). Axial T2WI-FS (B) showed heterogeneous hyperintense with a hypointense lobulated rim (blue arow). The tumor showed heterogeneous high signal intensity on DWI (C). Axial gadolinium-enhanced T1-weighted image (D) showed heterogeneous enhancement with a hypointense rim. Time-intensity curve (TIC) was progressive ascending type (E, F). Its x-axis represents the time of the enhanced scan, from 0 seconds to 380 seconds, with the extension of time, the curve is on the rise.

Figure 2

Lesion surgically excised. The submandibular mass had a grey and white appearance with multifocal hemorrhagic areas on the cut surface. It was surrounded by tissues similar to capsule (blue arrow) and the attached salivary gland tissue (black arrow) was observed.

Figure 3

Microscopic image (A) of the excised specimen showing the tumor was located in the lymph nodes, and residual lymphoid tissue could be seen at the edge (HE×20). The tumor cells were arranged in a fence-like and woven pattern (B) (HE×100). The surrounding area of the tumor was accompanied by significant hyaline degeneration (C) (HE×100). The characteristic morphological asbestos-like fibrous nodules (D) (HE×200). SMA (E) was partially expressed in tumor cells (IHC×200). Cyclin-D1 (F) was diffusely expressed in tumor cells (IHC×200).