Pancreatic-type mixed acinar-endocrine carcinoma with alpha-fetoprotein production arising from the stomach: a report of an extremely rare case

Primary Pure Pancreatic -Type Acinar Cell Carcinoma of the Stomach: A Rare Entity with a Difficult Diagnosis and Review of the Literature

Acinar cell carcinoma is an uncommon tumour, representing only 1% to 2% of all exocrine pancreatic tumours. Pancreatic-type acinar cell carcinoma can occur in other organs, including the stomach, but it is extraordinarily rare. We report a case of a 51-year-old woman with a pancreatic-type pure acinar carcinoma of the stomach coexisting with a large cell B lymphoma synchronously, and a literature review of gastric carcinomas with pancreatic cell differentiation. At present there is a preoperative underdiagnosis of these tumours that could be minimized by including this entity in the differential diagnosis of gastric cancer and by performing immunohistochemical analysis with neuroendocrine markers and exocrine pancreatic enzymes.

Mixed adenoneuroendocrine carcinomas of stomach and ampulla of vater after curative-intent resection: a single center cases series

Background

Mixed adenoneuroendocrine carcinoma is a rare clinical manifestation, especially in the gastric and ampullary. The purpose of this study was to investigate the clinicopathological features and prognosis of mixed adenoneuroendocrine carcinoma in the gastric and ampullary and summarize related treatment suggestions.

Methods

In all, 32 cases of mixed adenoneuroendocrine carcinoma in the gastric and ampullary that were diagnosed from resected specimens were analyzed from 2009 to 2015. The corresponding demographic, clinicopathological and survival data were retrospectively reviewed.

Results

The 1-year, 3-year and 5-year survival rates were 78.1%, 28.1 and 9.4%, respectively, and the median overall survival was 28.0 months. In all, 75.0% (24/32) had lymph node metastasis at the time of initial diagnosis. A multivariate analysis revealed that TNM stage (HR 6.444 95%CI 1.477–28.121 P = 0.013), lymph nodes metastasis (HR10.617 95%CI 1.409–79.997 P = 0.022), vascular invasion (HR 5.855 95%CI 1.719–19.940 P = 0.005), grade of the adenocarcinoma component (HR 3.876 95%CI 1.451–10.357 P = 0.007) and CD56 positivity (HR 0.265 95%CI 0.100–0.705 P = 0.008) were independent predictors of overall survival.

Conclusions

Mixed adenoneuroendocrine carcinoma is an aggressive clinical entity with a poor prognosis. Taking both the neuroendocrine component and the adenocarcinoma component into consideration of optimal treatment is strongly recommended.

Title: pancreatic-type mixed acinar neuroendocrine carcinoma of the stomach: a case report and review of the literature

BACKGROUND

The majority of gastrointestinal tumors are adenocarcinomas. Rarely, there are other types of tumors, such as acinar cell carcinoma, and these are often called pancreatic-type acinar cell carcinomas. Among these tumors, some are differentiated into neuroendocrine components. A few of them are MiNENs.

CASE PRESENTATION

The patient was an 80-year-old male who was referred to our hospital for treatment of a pedunculated gastric tumor. It was 5 cm in diameter and detected in the upper gastric body with upper GI endoscopy conducted to investigate anemia. In the biopsy, although hyperplasia of gastric gland cells was noted, no tumor cells were found. Retrospectively, the diagnosis was misdiagnosed. An operation was arranged because bleeding from the tumor was suspected as a cause of anemia and because surgical resection was considered to be desirable for accurate diagnosis. Hence, laparoscopic and endoscopic cooperative surgery was performed. In the pathological examination, several types of epithelial cells that proliferated in the area between the mucosa and deep inside the submucosa were observed. These consisted of acinar-glandular/trabecular patterns and solid. A diagnosis of pancreatic-type acinar cell carcinoma of the stomach with NET G2 and G3 was made based on characteristic cellular findings and the results of immunostaining tests. Each of them consisted of more than 30% of the lesion; a diagnosis of pancreatic-type mixed acinar neuroendocrine carcinoma (pancreatic-type MiNEN) of the stomach or a type of gastric MiNEN was obtained. Anemia was resolved after the operation, and the patient was discharged from the hospital without perioperative complications.

CONCLUSIONS

Pancreatic-type ACC of the stomach that is differentiated into neuroendocrine tumors is very rare. Hence, we report this case along with a literature review.

Mixed Acinar-Endocrine Carcinoma (MAEC) Arising in Duodenal Pancreatic Heterotopia

Mixed acinar-endocrine carcinoma (MAEC) of the pancreas is a rare neoplasm, consisting of at least 25%–30% of acinar and neuroendocrine populations. Patients are often middle-aged and present with nonspecific symptoms. Imaging typically reveals a solid lesion in the pancreatic head. Management involves surgical resection and the overall prognosis is variable. Here, we present a case of a 48-year-old male who presented with a MAEC arising from duodenal pancreatic heterotopia. This is the one of the first cases, with histologic evidence, of MAEC arising from pancreatic heterotopia.

Malignant Transformation of Ectopic Pancreas

Malignant transformation of ectopic pancreas tissue is a diagnostic challenge as clinical symptoms and radiographic features of these tumors are non-specific. Given the rarity of these lesions, it is usually neither suspected nor included in the diagnostic workup of different tumors. We conducted a comprehensive literature review regarding malignancy arising from ectopic pancreas for a better understanding of its frequency, clinicopathological features, and prognosis. A literature search was performed in three major databases: PubMed, Cochrane, and Web of Science. Fifty-four well-documented cases of malignant ectopic pancreas were identified in the published literature. Our analysis provided the following observations: (1) there was a slight predominance of males over females; (2) most patients with malignant transformation of ectopic pancreas were middle-aged; (3) most commonly, the tumor was located in the stomach; (4) most tumors were adenocarcinomas; (5) most frequently, the malignancy arose within a type I heterotopia according to Heinrich classification; (6) macroscopically, a subepithelial-like appearance was most frequently observed; and (7) improved prognosis for ectopic pancreatic malignancies in comparison with reported survival data for orthotopic pancreatic cancer. Even if the majority of cases of ectopic pancreas are incidental findings and malignant transformation is a rare event, pancreatic heterotopy should be considered as a source of potentially malignant lesions.

Pancreatic mixed acinar-neuroendocrine carcinoma, a unique diagnostic challenge on FNA cytology: A small series of two cases with literature review

Mixed acinar-neuroendocrine carcinoma (MANEC) of the pancreas is a rare tumor. We present two cases of MANEC diagnosed on endoscopic ultrasound (EUS) guided fine-needle aspiration (FNA). The first patient is a 33-year-old male who had a 3.6 cm mass in the uncinate process and liver metastasis. The second patient is a 66-year-old male with a 10 cm mass in the pancreatic tail. The FNA smears from both cases were hypercellular with neoplastic cells in loosely cohesive clusters and many naked nuclei. In both cases, the tumor cells were positive for CKAE1/3, synaptophysin, chromogranin, and trypsin by immunohistochemistry. Final diagnoses of MANEC were rendered based on cytological features and immunohistochemical profiles. To date, 44 cases of MANEC have been reported in the English literature, only three of which were diagnosed on cytopathology specimens before surgical resection. Our report adds two more cases diagnosed on cytopathology alone. Herein, we discuss the various cytomorphologic and clinical features of MANEC and present a brief review of the literature. Diagn. Cytopathol.

Severe panniculitis and polyarthritis caused by acinar cell carcinoma arising from an ectopic pancreas

The pancreatitis, panniculitis and polyarthritis (PPP) syndrome is a rare condition caused by pancreatic diseases, such as acute or chronic pancreatitis or pancreatic carcinoma. We report the first case of PPP syndrome caused by metastatic acinar cell carcinoma from an ectopic pancreas. The symptoms were successfully managed by the treatment of the metastatic carcinoma. Pancreatic cytosteatonecrosis should be always considered in a patient who is showing symptoms of panniculitis and polyarthritis.

Severe panniculitis and polyarthritis caused by acinar cell carcinoma arising from an ectopic pancreas

The pancreatitis, panniculitis and polyarthritis (PPP) syndrome is a rare condition caused by pancreatic diseases, such as acute or chronic pancreatitis or pancreatic carcinoma. We report the first case of PPP syndrome caused by metastatic acinar cell carcinoma from an ectopic pancreas. The symptoms were successfully managed by the treatment of the metastatic carcinoma. Pancreatic cytosteatonecrosis should be always considered in a patient who is showing symptoms of panniculitis and polyarthritis.

Gastric mixed adenoneuroendocrine carcinoma: correlation of histologic characteristics with prognosis

Gastric mixed adenoneuroendocrine carcinomas (MANECs) are rare, with both the exocrine and neuroendocrine components exceeding 30% volume. Several classifications for MANECs have been proposed, yet they have not been clinically evaluated. The aim of this study was to evaluate the correlation between tumor grade, histologic characteristics, and prognosis of gastric MANECs. We collected eligible 14 cases in our series and 31 cases in the literature and compared the prognostic difference among gastric MANECs with different histologic characteristics. Gastric MANECs could be divided into subgroups according to tumor grade of the neuroendocrine component and adenocarcinoma types. The high grade and large proportion of neuroendocrine component correlated with aggressive behavior and a tendency of poor clinical outcome. Gastric MANECs with a poorly differentiated adenocarcinoma showed a significant lower survival rate than did MANECs with a differentiated adenocarcinoma or mucin-producing carcinoma (P = .0008). Gastric MANECs were a heterogeneous group with different tumor grades, histologic subtypes, combination patterns, and patient outcomes. Previous classifications were evaluated. This study proves that histologic characteristics correlate with clinical outcomes. Our findings are complements to the latest prognostic classification.

A case of hyperfunctioning pancreatic mixed adenoneuroendocrine carcinoma (MANEC) arising from ectopic pancreatic tissue in the liver

We report the case of a hyperfunctioning mixed adenoneuroendocrine carcinoma (MANEC) arising from ectopic pancreatic tissue in the liver. To our knowledge, the imaging appearance of a MANEC in the liver has never been reported. Literature on MANEC and its imaging features, including its appearance on the MR hepatobiliary phase and differential considerations, are reviewed and discussed.

Pure pancreatic-type acinar cell carcinoma of the stomach: a case report

Acinar cell carcinoma is an uncommon carcinoma of the exocrine pancreas. On very rare occasions it has been reported in ectopic sites, sometimes with, but usually without contiguous heterotopic pancreatic tissue. Whilst mixed and composite glandular tumours have also been described, pure pancreatic-type acinar cell carcinomas arising in the stomach are very rare.

The CT findings of pancreatic acinar cell carcinoma in five cases

OBJECTIVES

The aim of this study is to analyze the computed tomographic (CT) findings of pancreatic acinar cell carcinoma (ACC).

MATERIALS AND METHODS

The CT features and clinical presentations of five patients (four men, one woman; mean age, 52 years) with pathology-proven pancreatic ACC were reviewed. The image characteristics included the lesion location and size, the exophytic nature of the tumor, intratumoral hemorrhage, calcification, the presence of cystic or necrotic components, bile or pancreatic duct dilation, attenuation on the noncontrast image, attenuation on the arterial- and venous-phase images, peripancreatic invasion, peripancreatic lymphadenopathy, and distant metastases.

RESULTS

The tumors were located at the pancreatic tail in three cases and at the pancreatic head in two cases. The average lesion size was 5.3 cm. Exophytic features and cystic/necrotic components were found in 80% (4/5) and 60% (3/5) of cases, respectively. The ACC showed a mild hypodense appearance on noncontrast CT in 100% (3/3) of cases and a hypodense appearance on arterial-/venous-phase CT in 80% (4/5) of cases. The exception was one lesion that showed a significantly hyperdense appearance and a mildly hyperdense appearance on the arterial- and venous-phase images. None of the CT images showed enhancement of a capsule, calcification, intratumoral hemorrhage, bile or pancreatic duct dilation, vascular encasement, or distant metastatic disease, but three cases showed peripancreatic invasion and lymphadenopathy.

CONCLUSIONS

With persistent mild enhancement, the typical ACC appears as an exophytic tumor with a focal cystic/necrotic component and the lack of ductal dilatation. The predilection for older male patients and elevated serum alpha fetoprotein are useful clinical features for confirming an ACC diagnosis.

The prevalence of pancreatic acinar differentiation in gastric adenocarcinoma: report of a case and immunohistochemical study of 111 additional cases

Although pancreatic acinar metaplasia in the gastric mucosa is well recognized in chronic gastritis, gastric carcinoma with acinar differentiation is very rare. We encountered a case of gastric adenocarcinoma with prominent histologic and immunohistochemical features of pancreatic acinar differentiation in the absence of identifiable heterotopic pancreatic tissue. Distinct glandular and diffuse patterns of adenocarcinoma were also present, and there was focal mucin production. The tumor strongly expressed pancreatic exocrine enzymes trypsin and chymotrypsin, and focal neuroendocrine staining was also present. To investigate the prevalence of acinar differentiation in histologically typical gastric cancers, we performed immunohistochemical staining for trypsin and chymotrypsin on a tissue microarray containing 111 conventional gastric adenocarcinomas (60 intestinal, 28 mixed, 22 diffuse type, and 1 undifferentiated). No obvious morphologic evidence of acinar differentiation was identified in any of the 111 cases. Although some cases showed equivocal staining for at least 1 pancreatic exocrine enzyme on the initial tissue microarray sections, repeat immunohistochemical staining on representative whole-tissue sections failed to reproduce positive staining. Thus, acinar differentiation is rare in gastric adenocarcinomas, other than in histologically unusual cases such as the one we report, and in others from the literature, which are reviewed.

Mixed Adenoneuroendocrine Carcinomas (MANECs) of the Gastrointestinal Tract: An Update

The systematic application of immunohistochemical techniques to the study of tumors has led to the recognition that neuroendocrine cells occur rather frequently in exocrine neoplasms of the gut. It is now well known that there is a wide spectrum of combinations of exocrine and neuroendocrine components, ranging from adenomas or carcinomas with interspersed neuroendocrine cells at one extreme to classical neuroendocrine tumors with a focal exocrine component at the other. In addition, both exocrine and neuroendocrine components can have different morphological features ranging, for the former, from adenomas to adenocarcinomas with different degrees of differentiation and, for the latter, from well differentiated to poorly differentiated neuroendocrine tumors. However, although this range of combinations of neuroendocrine and exocrine components is frequently observed in routine practice, mixed exocrine-neuroendocrine carcinomas, now renamed as mixed adenoneuroendocrine carcinomas (MANECs), are rare; these are, by definition, neoplasms in which each component represents at least 30% of the lesion. Gastrointestinal MANECs can be stratified in different prognostic categories according to the grade of malignancy of each component. The present paper is an overview of the main clinicopathological, morphological, immunohistochemical and molecular features of this specific rare tumor type.

Peri-ampullary mixed acinar-endocrine carcinoma

Mixed acinar-endocrine carcinomas (MAEC) are rare tumors of the pancreas. We present the case of a patient with periampullary tumor that presented with painless jaundice and after investigation was found to have MAEC. He underwent pancreaticoduo-dunectomy with tumor free margins and negative lymph nodes. The patient presented with local recurrence and liver metastasis after 1 year and is on chemotherapy with stable lesions 30 months after the diagnosis.

Pancreatic acinar-like adenocarcinoma of the proximal stomach invading the esophagus

The aim of this study was to systematically investigate clinicopathologic features of the recently described pancreatic acinar-like adenocarcinoma of the proximal stomach invading the esophagus (n = 43). Patient median age was 66 years (range, 51-90 years). The male-to-female ratio was 7.6. Grossly, pancreatic acinar-like adenocarcinoma tumors were nonencapsulated with the median size of 5.5 cm (range, 2-10.5). Bormann's types 1 to 4 tumors were in 7%, 9%, 67%, and 16% cases, respectively. Frank necrosis, hemorrhage, and cysts were rare or absent. Lymphovascular (81%), perineural (74%), and lymph node (81%) invasions were more common in the pancreatic acinar-like adenocarcinoma than in the non-pancreatic acinar-like adenocarcinoma (n = 94) groups. Microscopically, pancreatic acinar-like adenocarcinoma tumors showed acinar (78%), micropapillary (12%), microcystic, solid, trabecular, and mixed neuroendocrine or signet ring (33%) patterns of growth. No adenosquamous differentiation was noted in the pancreatic acinar-like adenocarcinoma group. Nuclei were round to oval with thickened nuclear membrane, stippled chromatin, and single prominent nucleoli. Mitotic figures were variable. The cytoplasm was moderate, eosinophilic, finely granular, and diffusely immunoreactive to the α1-chymotrypsin antibody in all cases to various degrees. Tumor stroma was nondesmoplastic, delicate, and fibrovascular. Pancreatic acinar-like adenocarcinoma tumors staged pI, pII, pIII, and pIV were in 2%, 21%, 70%, and 7% of cases, respectively. The median number of follow-up months after surgery was 29. The 2-year survival rate was 67%, lower than that (73%) in the non-pancreatic acinar-like adenocarcinoma group. A worse overall survival trend was found for patients in the pancreatic acinar-like adenocarcinoma than in non-pancreatic acinar-like adenocarcinoma groups, but the difference was not statistically significant. Age older than 75 years and overall pathology stage were independent risk factors.

Low-grade salivary duct carcinoma of the parotid gland: report of a case with immunohistochemical analysis

Salivary duct carcinoma (SDC) is a highly aggressive malignancy of the salivary glands. However, one type of SDC, which shows minimal invasion and better prognosis, is known as low-grade SDC (LG-SDC). This report presents an additional case of LG-SDC of the parotid gland. The patient was a 38-year-old Japanese woman who noticed painless swelling of the left parotid region. Grossly, the cut surface of the tumor was cystic. Microscopically, the tumor showed a multicystic pattern, which was lined by eosinophilic to clear atypical cells with cribriform or Roman bridge patterns. An immunohistochemical examination revealed the tumor was positive for cytokeratin (CK) 7 and epithelial membrane antigen, partially positive for androgen receptor and gross cystic disease fluid protein-15, and diffusely positive for Her-2/Neu, progesterone, and estrogen receptors. The cancer cells showed focal immunopositivity for S-100 protein. Immunostaining for p63, CK14, and calponin showed an in situ pattern in most areas of this tumor, whereas the tumor showed minimal invasion. The cancer cells were diffusely positive for MUC1 and MUC6 and focally positive for MUC2 and MUC4. Finally, the tumor was diagnosed to be LG-SDC. The differential diagnosis and the mucin pattern were evaluated.