Endoscopic ultrasound-guided fine-needle aspiration cytology of peripheral nerve-sheath tumors

Retrorectal schwannoma in a middle-aged female: A case report

INTRODUCTION AND IMPORTANCE

Primary sacral and presacral lesions are uncommon and pose a significant diagnostic dilemma. Retrorectal schwannoma is a benign primary presacral lesion that is extremely rare and presents with non-specific symptoms.

CASE PRESENTATION

A 42-years-old, female patient was admitted for lower-back pain for seven days. The retrorectal mass was detected on imaging, and she underwent laparoscopic excision. Pathological examination revealed a rare retrorectal schwannoma.

CLINICAL DISCUSSION

Retrorectal location of schwannomas is rare and the preoperative diagnosis is very difficult as the clinical features and the radiological features are non-specific. In addition, these tumors can be found incidentally on routine rectal or pelvic examinations. As these tumors are benign, encapsulated, and non-invasive, this entity has an excellent prognosis. Despite the tumors' rarity and variety, we concur with the literature that surgical management is required to obtain a clear diagnosis and avoid consequences such as malignant transformation.

CONCLUSION

Retrorectal Schwannoma presents a diagnostic and therapeutic challenge. Identification is important because surgical excision, either open or laparoscopic, is curative.

Mesenchymal neoplasms of the tubular gut and adjacent structures: experience with EUS-guided fine-needle aspiration cytopathology

INTRODUCTION

Unlike epithelial malignancies, mesenchymal neoplasms arising within the tubular gut are less often encountered in endoscopic ultrasound-guided (EUS) fine-needle aspiration biopsies (FNABs). Nonetheless, preoperative diagnosis of such neoplasms has important therapeutic and prognostic value. We report our experience with this category of neoplasms from the past decade.

MATERIALS AND METHODS

We performed a 10-year retrospective search at our respective institutions to identify EUS-guided FNAB cases of mesenchymal neoplasms arising from the tubular gut wall and closely adjacent structures. Cytopathologic diagnoses were compared to corresponding surgical pathology (SP) when available. Cases with either no confirmatory cell block (CB) immunohistochemical (IHC) staining, or no SP were excluded.

RESULTS

Two-hundred eighty-two cases (M:F = 1:1; age range: 25-94 years, mean age = 60 years) of EUS-guided FNAB from the tubular gut met our criteria. Onsite adequacy was performed on nearly all cases. Case numbers: 209 gastrointestinal stromal tumors (GIST), 58 smooth muscle neoplasms, and 15 miscellaneous neoplasms. Of these, 188 (67%) had SP follow-up. We found that 258 (91%) aspirates had a correct specific diagnosis, 3 (1%) were nondiagnostic, 18 (6%) had indeterminate diagnoses, and 3 (1%) had incorrect diagnoses (2 leiomyosarcomas mistaken as leiomyoma, and 1 fibrosclerotic lesion mistaken as inflammatory pseudotumor). Of 94 cases with no SP, all had a specific cytologic diagnosis based on confirmatory IHC staining from the CB including 61 GISTs, 29 smooth muscle neoplasms, and 4 miscellaneous tumors.

CONCLUSION

This study endorses the clinical utility of EUS-guided FNAB in the diagnosis of tubular gut mesenchymal neoplasms. A definitive and accurate diagnosis is possible in over 90% of cases, chiefly when cytomorphology is coupled with optimal cellularity and IHC from a concurrent CB. EUS-guided FNAB diagnosis of mesenchymal tubular gut neoplasms may play an important role in determining neoadjuvant therapy as targeted therapy evolves.

Endoscopic ultrasound-guided fine-needle aspiration biopsy of gastric schwannoma: Cytomorphologic features and diagnostic pitfalls

Schwannoma rarely occurs in the stomach. We present a case of gastric schwannoma, which was initially evaluated by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsy and confirmed by surgical resection. The patient was a 57-years-old woman with history of dyspepsia, who was found to have a large submucosal mass in the stomach. EUS-FNA showed scant spindle cells with abundant lymphocytes. The spindle cells were immunoreactive with S100, while negative for CD117, desmin, and CD34. The lymphocytes were mixed B-cells and T-cells. Immunostaining, flow cytometry, and molecular testing showed no evidence of B-cell lymphoma. The diagnosis of gastric schwannoma was confirmed by histopathological evaluation of the resected tumor. Gastric schwannoma has unique features of mixed spindle cells and lymphocytes. The tumor should be differentiated from other gastric mesenchymal tumors, and lymphoproliferative disorder is a pitfall.

Abdominal schwannomas: case report with literature review

Schwannomas are rare tumors that arise from Schwann cells in neural sheaths. They are commonly found in the central nervous system, spinal cord, or peripheral nerves of the body. Occasionally, they occur in the gastrointestinal tract, with the stomach being the most common site. However, colorectal and retroperitoneal schwannomas are very rare. Preoperative diagnosis is often difficult and definitive treatment entails surgical excision. We herein present 3 cases of intraabdominal schwannomas.

Cytologic findings of gastric schwannoma: a case report

Spindle cell lesions of the stomach are rare. They usually affect the submucosa or muscularis propria and therefore can be sampled by endoscopic fine needle aspiration. The most common tumor in this category is gastrointestinal stromal tumor (GIST), followed by leiomyoma and gastric schwannoma. Gastric schwannoma is a benign tumor of neuroectodermal origin that has overlapping morphologic/cytologic features with GIST and leiomyoma. Gastric schwannomas differ from peripheral schwannomas by lacking a capsule, Verocay bodies, Antoni B areas, and thick-walled vessels. They are characterized morphologically by poorly defined borders, cuffs of lymphoid tissue and a haphazard spindle cell proliferation. We present here the cytologic and histopathologic features of a gastric schwannoma. The tumor was composed of spindle cells with delicate eosinophilic cytoplasm and wavy nuclei, with an associated conspicuous lymphoid backdrop. The latter feature raised the possibility of a lymphoid lesion, a problem cytopathologists should be aware of.

Schwannoma of ascending colon treated by laparoscopic right hemicolectomy

Schwannomas of the colon are rare and are difficult to diagnose preoperatively, since they often defy endoscopic and radiographic detection. Immunohistochemical stains are useful postoperatively to confirm this tumor, but more reliable diagnostic techniques (such as colonoscopic biopsy with immunohistochemistry) have emerged to enhance preoperative diagnostic accuracy. Here we report an instance of schwannoma arising in the ascending colon, where immunohistochemical staining of a preoperative biopsy facilitated diagnosis. After laparoscopic resection, histologic examination was confirmatory.

Cystic pancreatic schwannoma in a 46-year-old man

Pancreatic schwannomas are a rare benign mesenchymal neoplasm of the pancreas. They are thought to arise from the epineurium of either autonomic sympathetic or parasympathetic fibers, which course through the pancreas with the vagus nerve. Large pancreatic schwannomas often undergo cystic change, which causes them to be often confused with other more common cystic pancreatic neoplasms preoperatively. The radiological, histologic, and immunohistochemical findings of pancreatic schwannomas are consistent with those of neoplasms found in other sites. Treatment is by surgical resection, and the prognosis is excellent. The awareness and, to some extent, knowledge of less common tumors in the pancreas are needed to achieve the diagnosis. We discuss the clinical and pathologic features and differential diagnosis of cystic pancreatic tumors.

Granular cell tumor of hypopharynx: report of a rare case

Granular cell tumor is a rare tumor, probably of Schwann cell origin. The head and neck are most frequently affected, but hypopharyngeal lesion is extremely rare. We report the seventh case of hypopharyngeal granular cell tumor. Immunohistochemical staining for S100 protein is helpful for the correct diagnosis. There is some possibility of malignancy despite absence of histological evidence, thus the treatment is exclusively surgical resection. The microlaryngoscopic approach is feasible for hypopharyngeal lesions in most cases. Recurrence can occur even after appropriate resection.

Esophageal leiomyosarcoma diagnosed by endoscopic ultrasound-guided fine-needle aspiration

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has proven itself to be a reliable method for the diagnosis of gastrointestinal stromal tumors and other gastrointestinal mesenchymal neoplasms. The diagnosis and distinction of these entities remain important, as these neoplasms have different prognoses and treatment options. We present a case of a 14.5-cm esophageal mass in a 67-yr-old woman sampled by EUS-FNA. Smears showed a cellular, spindle cell lesion with marked cytologic and nuclear pleomorphism. A cell block showed neoplastic cells reacting strongly with antibodies to smooth muscle antigens and not with antibodies to keratin, CD34 and CD117. Resection confirmed the diagnosis of esophageal leiomyosarcoma. To the best of our knowledge, this represents the first reported case of an esophageal leiomyosarcoma diagnosed by EUS-FNA. Clinical, imaging, and cytologic features as well as differential diagnosis are discussed.

Review of endoscopic ultrasound-guided fine-needle aspiration cytology

This review, based on the Hennepin County Medical Center experience and review of the literature, vastly covers the up-to-date role of endoscopic ultrasonography (EUS) and EUS-guided fine-needle aspiration (FNA) in evaluating tumorous lesions of the gastrointestinal tract and adjacent organs. Emphasis is given to the tumoral and nodal staging of esophageal, pulmonary, and pancreatic cancer. This review also discusses technical, pathological, and gastroenterologic aspects and the role of the pathologist and endosonographer in the evaluation of these lesions, as well as the corresponding FNA cytology and differential diagnosis.

Fine-needle aspiration cytology of pancreatic somatostatinoma: the importance of immunohistochemistry for the cytologic diagnosis of pancreatic endocrine neoplasms

Pancreatic somatostatinoma is a rare pancreatic endocrine neoplasm representing as little as 1% of pancreatic endocrine neoplasms (PENs). The histologic features of this tumor are like those of other PENs, except that it commonly forms acinar structures and often has cells with abundant, granular cytoplasm. We have recently encountered two of these neoplasms sampled by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA). We discuss the cytologic and immunohistochemical findings of these two cases and the cytologic similarities these neoplasms share with pancreatic acinar-cell carcinoma (PACC). We review the cytologic features of PEN and PACC and discuss the importance of cell block immunohistochemistry in the diagnosis of pancreatic neoplasia sampled by EUS-guided FNA.

The cytological spectrum of chronic pancreatitis

Chronic pancreatitis (CP) refers to a spectrum of changes generally seen after repeated injury that ranges histologically from mild fibrosis to extensive fibroinflammatory replacement of acinar tissue with accumulation of calcific debris. Because CP can share clinical and radiological features with malignancy, it often is sampled by fine-needle aspiration (FNA). The cytology files at Hennepin County Medical Center (HCMC) were searched for 20 consecutive cases of CP sampled by FNA. Clinical data and cytological findings were recorded. A spectrum of cytological findings typifies aspirates of CP. In most cases, mixed inflammation with debris and calcific material is present. Often, ductal cells are present and at most show mild atypia but generally appear organized. Often, fibrotic acinar tissue also is present while definitive islets are identified only rarely. Although these cytological findings were consistent with CP, 3 of 17 patients with follow-up were found to have pancreatic ductal adenocarcinoma.

Pitfalls in endoscopic ultrasound-guided fine-needle aspiration and how to avoid them

Although a broad range of pancreatic, gastrointestinal, thoracic, and abdominal pathology may be sampled by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA), certain difficulties tend to recur because of the frequency of certain sample types and because of the nature of their individual cytomorphologic profiles. With this in mind, we review certain pitfalls that may befall cytopathologists with EUS-guided FNA. We discuss the diagnosis of pancreatic ductal adenocarcinoma and of other pancreatic epithelioid tumors including pancreatic endocrine neoplasms, solid pseudopapillary tumors, and acinar cell carcinomas. We also discuss the diagnosis of pancreatic cystic neoplasia including intraductal papillary mucinous neoplasms and mucinous cystic neoplasms and the diagnosis of gastrointestinal mesenchymal neoplasia with particular attention to gastrointestinal stromal tumors. Finally, we discuss the interpretation of lymph node aspirates.

Endoscopic ultrasound-guided fine-needle aspiration of lymph nodes: The Hennepin County Medical Center experience

Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) allows for the sampling and diagnosis of lesions of the gastrointestinal system and adjacent tissues. It has also proved helpful with the sampling of lymphadenopathy both for the staging of malignancy and for the diagnosis of lymphadenopathy of other causes. We review our experience with EUS-guided FNA of lymph nodes. The cytology files were searched at Hennepin County Medical Center (HCMC) for all cases of lymph nodes sampled by EUS. Clinical history, biopsy site, diagnosis, and follow-up information (including ancillary testing) were reviewed. Between January 1, 2000 and December 5, 2002, 217 lymph nodes from 185 different patients were sampled by EUS at HCMC. Biopsy sites included 62 mediastinal, 9 paraesophageal, and 146 intra-abdominal lymph nodes. Diagnoses were as follows: metastatic non-small cell carcinoma (n = 69); benign, reactive lymph node (n = 76); granulomatous lymphadenopathy (n = 18); malignant lymphoma (n = 7); atypical-suspicious for malignancy (n = 5); metastatic small cell carcinoma (n = 2); necrotic debris (n = 4), and foreign material (n = 1); 35 cases were nondiagnostic (16.1%) in 22 of 185 patients (11.9%). Ancillary tests including flow cytometry, cytogenetics, and cultures were performed. EUS-guided FNA of mediastinal and intra-abdominal lymph nodes provides diagnostic material from which ancillary testing may be performed.