Schwannoma arising in mediastinal lymph node diagnosed by endobronchial ultrasound

Schwannoma diagnosed by endobronchial ultrasound-guided intranodal forceps biopsy using standard-sized biopsy forceps: A case report

Schwannomas are classified as neurogenic tumors and are the most frequent nerve sheath tumors in the paravertebral mediastinum. Recently, the addition of endobronchial ultrasound-guided intranodal forceps biopsy (EBUS-IFB) using standard-sized biopsy forceps (SBFs) to endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for metastatic lymph nodes in lung cancer patients reportedly improved the quality and quantity of the obtained specimens without significant complications. However, reports on the usefulness of this technique for benign diseases remain scarce. Here we report a case of schwannoma in the middle mediastinum, which was diagnosed by EBUS-IFB using SBFs, despite inadequate specimens obtained via EBUS-TBNA. An 80-year-old woman presented with dyspnea and a 5-cm sized middle mediastinal tumor. EBUS-TBNA and EBUS-IFB using SBFs were performed for histological diagnosis. No complications were associated with the bronchoscopy procedure, and schwannoma was solely diagnosed using the EBUS-IFB specimens. EBUS-IFB using SBFs is potentially useful for diagnosing benign diseases, including schwannomas, which are often difficult to diagnose with EBUS-TBNA.

Primary lipoblastic nerve sheath tumor in an inguinal lymph node mimicking metastatic tumor: a case report and literature review

Lipoblastic nerve sheath tumors of soft tissue are characterized as schwannoma tumors that exhibit adipose tissue and lipoblast-like cells with signet-ring morphology. They have been documented to arise in various anatomic locations, including the thigh, groin, shoulder, and retroperitoneum. However, to our knowledge, this tumor has not been previously reported as a lymph node primary. We present herein the first case of a benign primary lipoblastic nerve sheath tumor arising in an inguinal lymph node in a 69-year-old man. Microscopic examination revealed a multinodular tumor comprising fascicles of spindle cells, as well as adipocytic and lipoblast-like signet-ring cell component in the context of schwannoma. Despite the presence of some bizarre cells with nuclear atypia, no obvious mitotic activity or necrosis was observed. Immunohistochemical analysis showed strong and diffuse expression of S-100, SOX10, CD56, and NSE in the spindle cells as well as in the signet-ring lipoblast-like cells and the mature adipocytes. Sequencing analysis of the neoplasm identified six non-synonymous single nucleotide variant genes, specifically NF1, BRAF, ECE1, AMPD3, CRYAB, and NPHS1, as well as four nonsense mutation genes including MRE11A, CEP290, OTOA, and ALOXE3. The patient remained alive and well with no evidence of recurrence over a period of ten-year follow-up.

Endobronchial ultrasound-guided transbronchial needle aspiration as a diagnostic modality for schwannoma: A case report

INTRODUCTION

Schwannomas are the most common nerve sheath tumors in the paravertebral mediastinum. Although radiological imaging is helpful in diagnosing schwannomas, a definitive diagnosis is dependent on pathological features of a surgical specimen. For patients who require preoperative diagnosis, an incisional biopsy using minimally invasive surgery is preferred. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is less commonly used for suspected schwannomas.

PATIENT CONCERNS

A 48-year-old woman presented to the clinic with complaints of productive cough for >1 month, expectorating yellow and mucoid sputum approximately 4 to 5 times per day. Chest computed tomography revealed a well-circumscribed, homogeneous, soft tissue mass lesion in right upper posterior mediastinum, measuring 55 mm × 44 mm. Vocal fremitus in the right upper lung was diminished, the percussion note was slightly dull, and breath sounds were slightly reduced on auscultation. The patient was a nondrinker and nonsmoker, with no other relevant medical history. There was no significant relevant family medical history.

DIAGNOSIS

Complete blood count and blood biochemistry were within normal limits, except for an elevated erythrocyte sedimentation rate (32 mm/h). EBUS-TBNA was performed and histopathological findings were consistent with schwannoma.

INTERVENTIONS

The patient underwent schwannoma excision by thoracoscopy. Pathological findings from the surgical specimen were consistent with the EBUS-TBNA results. Based on EBUS-TBNA and postsurgical pathology, the patient was diagnosed with a right upper mediastinal schwannoma (Antoni B).

OUTCOMES

The patient experienced an uneventful postoperative recovery with no adjuvant therapy and was discharged on April 18, 2017. The patient has been followed up for 4 years and has not experienced any symptoms.

CONCLUSIONS

Cell blocks obtained from EBUS-TBNA afford the possibility of cytological examination and immunocytochemical staining, which can confirm diagnosis of schwannoma.

Intranodal Neurofibroma: A Case Report and Literature Review

PURPOSE

To report a case of neurofibroma involving the lymph nodes and to perform a literature review on this topic.

OBSERVATIONS

A 72-year-old woman with a history of neurofibromatosis and biopsy-proven malignant melanoma of the left forearm underwent wide local excision of the malignant lesion along with sentinel axillary lymph node biopsy. Histological examination of axillary nodes revealed diffuse neurofibromatosis within 2 lymph node capsules. A thorough review of the English literature pertaining to intranodal neurofibroma was performed by querying Google Scholar and PubMed. Only 5 cases of intranodal neurofibroma have been described until now.

CONCLUSIONS AND IMPORTANCE

Neurofibroma involving the lymph nodes is rare and this is the first reported case that is shown to diffusely involve the intracapsular space. Furthermore, intranodal neurofibroma can represent a diagnostic pitfall in the evaluation of sentinel lymph nodes for metastatic melanoma.

Cervical intranodal schwannoma - a rare diagnosis

Intranodal schwannoma is a rare benign tumor, which originates from the peripheral nerve sheath (Schwann cells), fewer cases being reported with lymphatic involvement. We present the case of a middle-aged female patient, with one-year growing mass in the lateral-cervical area, in intimate relation with the vascular package of the neck. Preoperative cervical computed tomography examination showed the tumor features. There was no intraoperative complication, with the piece being completely removed. The morphological examination revealed the structure of a lymph node, and after Hematoxylin-Eosin staining, there were eosinophilic cytoplasm, euchromatic nuclei, with round, elongated or slightly wavy form and reduced pleomorphism, rare degenerative nuclear atypia, and no mitotic activity nor necrosis. The expression of S100 protein on immunohistochemistry, along with negative results for smooth muscle actin and desmin sustained the diagnosis of intranodal schwannoma of the neck. With a low index of cellular proliferation (Ki67), this case is in line with the reported features of schwannoma having extremely rare malignant transformation.