Case 1
A three-year-old girl presented a painless mass in front of the right ear that has been present for one and a half years. (Fig1) Regular anti-infection treatment was not effective. The mass was biopsied before surgery, histology revealed the diagnosis of NF. Temporal bone CT showed an irregular soft tissue mass with uniform density in the anterior and inferior part of the right external auditory canal. On MR image, the mass showed hypointense on T1-weighted imagine (T1WI) signal related to skeletal muscle. Hyperintense signals were showed on T2-weighted imagine (T2WI) and STIR sequences. US exam showed a 41×21×33 mm ovoid hypoechoic nodule with distinct margins.
The child underwent surgery under general anesthesia. We made a longitudinal incision along the preauricular bulge. Then cut the subcutaneous tissue, and exposed the mass. The border of the mass was obvious. After completely resected, the specimen was sent to pathology. Histopathologically, the lesion was compatible with a diagnosis of NF. IHC staining showed positivity for SMA and catenin, CD68 was focally positive, Ki-67 was 10% positive and CD34, S-100 and Desmin were negative. There was no recurrence 31 months after operation by MR image.
Case 2
A one year and five months boy was admitted to our department with a mass in his right pinna during four months(Fig2). He went through two surgeries to cut off the mass before this admission. Besides, the mass caused no pain before surgery. The pathology showed myofibroblastic tumor. After the second surgery the wound did not heal. Then the mass reappeared and grew rapidly. Anti-infection treatment was administered during this period but it doesn’t work. The boy underwent MR image and US in our department after this admission. MRI demonstrated a nodule with an isointense on T1WI and an hyperintense on T2WI and STIR sequences. Enhanced MRI showed inhomogeneous enhancement at the edge of the lesion and no enhancement in the interior of the lesion. US examination revealed a solid mass of irregular hypoechoic, which had an un-even internal echo. The mass was about 30×18×28 mm in size.
The operative incision made from retroauricular sulcus. During the operation, it was seen that the lesion did not have a complete capsule with a rotten fish-like appearance and crisp texture. The mass did not penetrate the fascia layer behind the ear, but invaded the cartilage of the cavum concha forward. The incisal margins were sent to frozen pathology for several times until the incisal margins were negative. Triamcinolone acetonide was injected to the operation cavity at the end of the operation. The postoperative pathology confirmed the diagnosis of NF. IHC staining showed positivity for SMA, CD68 was focally positive, Ki-67 was 15% positive and CD34, Desmin, and S-100 were negative. FISH test result showed that 34% of 100 cells showed USP6 gene rearrangement. At present, it recovered well with nine months after operation.
Case 3
A one year and seven months girl with a painless and progressive mass at the external orifice of the left ear during six months(Fig3). And the mass broke and bled in the last month. Then a biopsy was performed in another hospital, and the pathological result was inflammatory granuloma. The mass showed a sign of enlargement after the biopsy. Temporal bone CT showed that an oval low-density tissue in the left auricle with surrounding soft tissue thickening. MR image features include hypointense relative to skeletal muscle on T1WI and Hyperintense on T2WI or STIR sequences with Inhomogeneous enhancement after contrast injection. The whole lesion was about 17×16×9 mm in US. In addition, the lesion did not show any intrinsic vascularity, though the surrounding soft tissue exhibited increased vascularity on doppler US examination.
We made a surgical incision along the edge of the mass. In the operation found that the tumor did not have a complete capsule and the texture is solid. The incisal margins were sent to frozen pathology, and the lesion was completely resected. Finally, the skin of the mastoid area was taken as a free skin flap and transplanted into the skin defect of the ear canal. IHC staining showed positivity for SMA and CD68, Ki-67 was 10% positive, and CD34, S-100, and Desmin were negative. The diagnosis of NF was made. FISH test result showed that 33% of 100 cells showed USP6 gene rearrangement. At present, it recovered well eight months after operation.
Table1 summarizes the clinical characteristics and examination data of the three children. The average age of onset was 14 months, with two girls and one boy. The maximum diameters of three lesions were 2.9 cm, 2.8 cm, 1.7 cm, respectively. All of the three children had no history of trauma. The anti-inflammatory treatment was ineffective in all three patients. Case 1 and case 3 had a history of biopsy, and case 2 had a surgical history of mass resection. These three masses were all surgically removed finally in our hospital. Regular follow-up was carried out after the operation and none of the three cases recurrence. They all have intact ear appearance.