Corticotropin-releasing hormone-secreting pancreatoblastoma in an adult patient

Adult Pancreatoblastoma: Report of 3 new Cases With Genetic Diversity and Autopsy Findings

We report the histopathological, immunohistochemical (IHC), and molecular findings in 3 patients with adult pancreatoblastoma, including 2 with autopsy features. The tumors were located in the tail and body of the pancreas, and the 2 autopsy examinations revealed liver and lung metastases. Histopathologically the neoplasms were composed of solid epithelial elements with nested or trabecular growth patterns, fibrous stroma, and squamoid clusters. Keratin 19 was positive mainly in squamoid corpuscles, and trypsin or chymotrypsin was positive in the acinar component. Neuroendocrine differentiation was observed in all tumors, and nuclear β-catenin expression in 2 tumors. Despite nuclear β-catenin expression, CTNNB1 mutation was found only in tumor 2. APC mutation was detected in tumor 1, and SMAD4 as well as MEN1 mutations in tumor 3. This last tumor also revealed chromosomal instability with many chromosomal losses and gains. The follow-up showed regional or distant metastases in all patients. Two patients died of disease after 3 and 26 months of follow-up and 1 patient is alive with no evidence of disease 6 years and 2 months after surgery. Adult pancreatoblastoma can display genetic heterogeneity, diverse histological appearance, and overlapping IHC findings. As a result, the differential diagnosis with other adult pancreatic tumors, such as acinar cell carcinoma, neuroendocrine neoplasm, solid pseudopapillary neoplasm, and mixed tumors may be challenging, especially when dealing with limited tumor tissue. The identification of squamoid corpuscles is essential for diagnosis. Although molecular findings might provide useful information, the integration of clinical, radiological, and histopathological findings is essential in pancreatoblastoma diagnosis.

Adult pancreatoblastoma: Current concepts in pathology

Adult pancreatoblastoma is an exceptionally rare malignant tumour of the pancreas that mimics other solid cellular neoplasms of the pancreas, which may pose diagnostic difficulties. Because of its rarity, little is known about its clinical and pathologic features. This article reviews the clinical and pathologic features of pancreatoblastoma in adults including differential diagnosis, treatment, and follow-up. Although pancreatoblastoma commonly occurs in childhood, there have now been more than 70 adult pancreatoblastomas described in the literature. There is a slight male predominance. There are no symptoms unique to pancreatoblastomas and adult patients are frequently symptomatic. The most common presenting symptom is abdominal pain. Grossly, the tumours are often large and well-circumscribed. Microscopically, pancreatoblastomas are composed of neoplastic cells with predominantly acinar differentiation and characteristic squamoid nests. These tumours are positive for trypsin, chymotrypsin, lipase, and BCL10. Loss of heterozygosity on chromosome 11p is the most common molecular alteration in pancreatoblastomas. Adult pancreatoblastomas are aggressive tumours with frequent local invasion, recurrence, and distant metastasis. Treatment consists of surgical resection. Chemotherapy and radiotherapy may have a role in the treatment of recurrent, residual, unresectable, and metastatic disease. It is important to distinguish pancreatoblastomas from morphological mimics such as acinar cell carcinomas, solid pseudopapillary neoplasms, and pancreatic neuroendocrine neoplasms.

Clinicopathological review of pancreatoblastoma in adults

Pancreatoblastoma (PB) is a rare malignant neoplasm of the pancreas with unknown etiology. It occurs mostly in the pediatric population with very rare documented cases in adults. This is a review of the case reports of the adult pancreatoblastoma in the literature. A total of 35 cases were identified and reviewed with the mean age of 41 years (range, 18-78 years) and the male sex accounted for 51.4% of the cases. Adult Pancreatoblastoma seem to have a predilection for the head of the pancreas which accounted for approximately 49% of the cases reviewed with an average size of 8 cm (range, 1.8-20 cm). The median follow up for patients was 15 months (range, 1-108 months) Metastatic disease and local infiltration of surrounding tissues is common with poor prognosis in adult patients. Preoperative diagnosis is difficult because of the unhelpful tumor markers in adults and the cellular heterogeneity of the tumor which makes fine needle aspiration cytology unreliable. Histopathological review of the tumor is essential for diagnosis. Pancreatoblastomas should be considered a differential diagnosis of solid and cystic pancreatic neoplasms. Surgical resection of the tumor is the treatment of choice with a variable combination with radiotherapy and chemotherapy.

Adult pancreatoblastoma: A case report and review of the literature

The present study describes the case of a 24-year-old patient who presented with obstructive jaundice and weight loss, and was diagnosed with pancreatoblastoma (PB). Abdominal imaging studies revealed a heterogenous lesion of the pancreatic head with dilatation of the common bile duct. The patient underwent pancreaticoduodenectomy, however, three months after surgery multiple liver and bone metastases were identified on follow-up computed tomography scans. Despite treatment with four cycles of systemic chemotherapy and five courses of radiofrequency ablation, the patient succumbed due to tumour dissemination 13 months after initial diagnosis. PB is a malignant tumour of the pancreas that typically occurs in the pediatric population. The aim of the present study was to highlight the aggressive behavior of this rare clinical entity, focusing on the pitfalls of pre-operative diagnosis and the lack of management strategy guidelines in adults. Preoperative diagnosis of PB based on radiographic features may be difficult, as the imaging characteristics are non-specific. Furthermore, cytology may also be misleading, as the neoplasm consists of multiple cell lines (acinar, ductal and neuroendocrine cells) and diagnosis depends largely on the identification of the distinctive histological characteristic of squamoid corpuscles, which present as nests of flattened cells with a squamous appearance. Despite the use of surgical resection and adjuvant chemoradiotherapy for the treatment of this malignancy, its aggressive nature means that PB is associated with a poor prognosis in adult patients.

The diagnosis and surgical treatment of pancreatoblastoma in adults: a case series and review of the literature

INTRODUCTION

Pancreatoblastoma is an extremely rare pancreatic neoplasm in adults. The aim of this study is to report our experience with adult pancreatoblastoma as well as review the cases reported in the literature in order to provide guidelines for the management of patients with this rare neoplasm.

METHODS

We have encountered three cases of pancreatoblastoma in adults at our institution in addition to the 30 cases reported to date in literature.

RESULTS

The median age of pancreatoblastoma in adults is 37 years (range, 18-78 years); men and women are similarly affected (male/female = 16/17). The behavior of pancreatoblastoma is clearly that of a malignant neoplasm, with local invasion, recurrence, and metastasis. Among the adult reported cases, at diagnosis or operation, metastasis and/or local invasion was found in 14 of 31 adult patients (46 %) (2 patients had no data) The survival was significantly higher in patients with resected tumor (resection only and resection + adjuvant chemo/radiotherapy) when compared to unresected patients (palliative chemo/radiotherapy and no treatment), (p = 0.008, HR = 0.20).

CONCLUSION

When disease is localized, the treatment of choice is a complete surgical resection. The role of adjuvant chemotherapy or radiotherapy is still unclear based on the very small number of patients treated.

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.