Fig. 13.

A 58-year-old patient presented with radiating pain to the right arm about eight years ago. MRI of the BP with (a) T1-weighted imaging with i.v. contrast and (b) T1-weighted TSE imaging showed small BP tumors on the right side. The patient had been operated on ten years earlier in the same region; the histopathological diagnosis was plexiform neurofibroma. Now, the patient was complaining of increasing symptoms from the left side of the neck. A hard mass could be palpated in the lateral neck triangle, and the patient's arm was tired after use. The new MRI of the BP with (a) T1-weighted imaging with fat suppression and i.v. contrast, (b) T1-weighted imaging, (c) T2-weighted mDIXON imaging, (d) T1-weighted mDIXON TSE with i.v. contrast, (e) T2-weighted mDIXON TSE imaging, and (f) T2-weighted mDIXON TSE MIP reconstruction showed multiple solid tumors in the lateral triangle of the neck (straight arrows). Because of the unclear symptoms and enlarged lymph nodes, the multidisciplinary team requested a biopsy. An ultrasound-guided core biopsy (g, h) with a 16-gauge needle (dashed arrow) from the most prominent lesion (curved arrow) was performed; no malignant cells were present.