Solid and papillary epithelial neoplasm of the pancreas. Report of a case with diagnosis by fine needle aspiration cytology

Cercariform cells: another cytologic feature distinguishing solid pseudopapillary neoplasms from pancreatic endocrine neoplasms and acinar cell carcinomas in endoscopic ultrasound-guided fine-needle aspirates

BACKGROUND

Solid pseudopapillary neoplasm (SPPN) is a rare tumor of unknown origin that occurs predominantly in the body or tail of the pancreas in young women. The authors recently identified cercariform (Greek: tailed) cells, similar to those described in urothelial carcinomas, as a consistent cytologic feature in ultrasound-guided fine-needle aspiration (EUS-FNA) samples from SPPNs. The objective of the current multi-institutional study was to define the value of these cells in the differential diagnosis of SPPN with other neoplasms characterized cytologically by the presence of monotonous, uniform cells in pancreatic aspirates: pancreatic neuroendocrine tumors (Pan-NETs) and acinar cell carcinomas (ACCs).

METHODS

The files of 4 academic hospitals were searched for SPPNs, Pan-NETs, and ACCs that were diagnosed by EUS-FNA. The slides were reviewed, and several cytologic features were recorded semiquantitatively to identify discriminating features between SPPNs, Pan-NETs, and ACCs.

RESULTS

From the analysis of 18 SPPNs, 4 ACCs, and 20 Pan-NETs, the following cytologic features were identified as common to all 3 neoplasms: single cells and rosettes/acinar cell groups, round-to-plasmacytoid cells, pale-to-granular cytoplasm, fine vacuoles, and binucleated cells. Papillary structures, cercariform cells, large cytoplasmic vacuoles, reniform nuclei, hyaline globules/magenta-colored material, and degenerative features (cholesterol crystals, calcifications, foam cells, or giant cells) were significantly more common in SPPNs. Prominent nuclear grooves were encountered in only 4 of 18 SPPNs.

CONCLUSIONS

The current results indicated that the presence of cercariform cells is another useful clue for the cytologic diagnosis of SPPN in challenging cases.

Clinical, imaging, and cytopathological features of solid pseudopapillary tumor of the pancreas: a clinicopathologic study of three cases and review of the literature

Solid pseudopapillary tumors are rare pancreatic neoplasms of uncertain pathogenesis that rarely metastasize and usually occur in young women. We describe the clinical, imaging, and cytopathological features of solid pseudopapillary tumor of the pancreas. We reviewed the clinical presentation, imaging, morphologic/immunochemical features, and follow-up of three women (age range 26-44). Cases 1, 2, and 3 presented with abdominal wall abscess, multiple endocrine neoplasia, and solid/cystic mass in the pancreatic head, respectively, and computed tomography of abdomen revealed solid/cystic masses with heterogeneous enhancement in body, tail and head of the pancreas, respectively. Case 2 also exhibited a left adrenal mass. Case 3 underwent endoscopic ultrasound of the pancreas, which showed a complex solid/cystic mass with septations. Sampling consisted of fine-needle aspiration (percutaneous or endosonography-guided), and additionally, core biopsy of the pancreatic mass and adrenal lesion in case 2. Aspirates and core biopsy revealed vascular structures with attached monotonous neoplastic cells in papillary-like arrays. Tumor cells had bland nuclear features with grooves, cytoplasmic periodic acid Schiff-positive hyaline globules, and associated myxoid/stromal fragments. Immunochemistry expressed alpha-1-antitrypsin, alpha-1-antichymotrypsin, vimentin, and focal neuron-specific enolase. Cases 1 and 3 underwent pancreatectomy with follow-up consisting of yearly imaging and no recurrences. Case 2 proved metastatic disease to adrenal gland and no follow-up was available. In the setting of typical clinical and imaging findings, an accurate preoperative diagnosis of pancreatic solid pseudopapillary tumor can be established by aspiration cytology and immunochemistry with or without concomitant core biopsy, on the basis of which clinicians decide treatment. This tumor can behave in a malignant fashion.

FNA diagnosis of recurrent sebaceous carcinoma

We describe fine-needle aspiration (FNA) diagnosis in a case of sebaceous carcinoma presenting as recurrent swelling eyelid. The patient, a 35-yr-old woman, presented with a gradually increasing painless mass in the left upper eyelid. She had a history of excisions of swelling at the same site over a period of 5 years. On FNA, the smears were cellular and demonstrated sheets, three dimensional clusters, and singly scattered polygonal tumor cells having centrally located hyperchromatic and pleomorphic nuclei and cytoplasmic microvacuolations. Oil red-O stain performed on air-dried smears showed positivity, confirming the presence of intracellular and extracellular lipid globules. A final impression of sebaceous carcinoma of the left upper eyelid was rendered, based on which the eyelid mass was radically excised. Subsequent histopathology confirmed the diagnosis. Despite wide excision, such tumors not uncommonly recur and metastasize. An early and accurate diagnosis of such lesions can be established on minimally invasive needle aspiration.

Metastatic extraocular sebaceous carcinoma with an occult primary

The cytological diagnosis of sebaceous carcinoma is based on the aspiration of tumor lobules with extensive sebaceous differentiation. However, these tumors may show a spectrum of cells ranging from basaloid to well-differentiated sebaceous. Extraocular sebaceous carcinoma is an uncommon tumor. An occult primary at initial presentation has not been described previously. A 60-yr old woman was referred to the fine-needle aspiration (FNA) clinic with a submandibular mass. The cytological diagnosis was mucoepidermoid carcinoma. Histopathologically, it was a sebaceous carcinoma metastatic to the submandibular lymph node. No primary tumor was identified. Six months later, she presented with a nodule at the angle of her mouth and a recurrence of the submandibular swelling. FNA cytology (FNAC) and histopathologic examination revealed a primary cutaneous sebaceous carcinoma with submandibular lymph node metastasis. A metastatic sebaceous carcinoma in the submandibular region with limited sebaceous differentiation and occult primary is another pitfall in the cytomorphological diagnosis of mucoepidermoid carcinoma.

Solid-pseudopapillary tumor of the pancreas: a neoplasm with distinct and highly characteristic cytological features

The solid-pseudopapillary tumor of the pancreas (SPTP) is an unusual low-grade malignant epithelial tumor affecting predominantly adolescent girls and young women. Although approximately 500 cases of SPTP have been described in the last 40 yr, its pathogenesis remains uncertain. However, the clinical features of this neoplasm are very characteristic and SPTP must be suspected in any young woman with a cystic or partially cystic pancreatic mass. In this report, we describe the cytologic features of seven cases of SPTP investigated by preoperative fine-needle aspirates. The analysis of the cytologic features in these cases and in 43 cases collected from the literature reveals that they are highly characteristic and quite distinct from those of other cystic or solid tumors of the pancreas. On this basis, a cytologic diagnosis of SPTP may be rendered with great confidence, not only in clinically typical examples, but also in unusual presentations, such as in older patients, in males, in ectopic locations, and in metastatic sites.

Solid and cystic tumor of the pancreas: clinicopathologic and genetic studies of four cases

BACKGROUND

Solid and cystic tumor (SCT) of the pancreas can be distinguished from other pancreatic neoplasms by its nearly exclusive occurrence in young women, and its favorable prognosis after complete resection.

METHODS

We experienced four cases with SCT of the pancreas, and analyzed these tumors by immunohistochemical and electron microscopic studies, as well as genetic analysis of ras oncogene mutation.

RESULTS

The presented cases expressed the neuron-specific enolase in two cases, alpha1-antitrypsin and alpha1-antichymotrypsin in two cases, and vimentin in one case, which indicated that this tumor originates from pleuripotential embryonic stem cells. No patients had mutations of K-ras gene in codon 12, and further genetic analysis is required to predict the malignant potential.

CONCLUSION

SCT of the pancreas appears to have limited malignant potential and the metastatic ratio is not high, although the tumor has local invasion. Therefore, an aggressive surgical approach seems fully justified.