Clara S. Heffess

Acinar Cell Carcinoma of the Pancreas: A Clinicopathologic Study of 28 Cases

We have examined the microscopic appearance, immunohistochemical staining properties, and clinical behavior of 28 cases of acinar cell carcinoma of the pancreas. Two of the tumors occurred in children. The adult patients ranged in age from 40 to 81 years (mean, 62 years). Males greatly outnumbered females, and most of the patients were white. Presenting symptoms were nonspecific, and jaundice was infrequent. The frequently reported complications from increased serum lipase levels (i.e., arthralgias and subcutaneous fat necrosis) were present in only 16% of the patients. Grossly, the tumors were relatively circumscribed and fleshy, averaging 10.8 cm, with occasionally extensive hemorrhage and necrosis. Microscopically, the tumors were very cellular and characteristically lacked a desmoplastic stroma. Acinar, solid, trabecular, and glandular patterns of growth were identified; individual tumors were usually mixed. Nuclei were round to oval, with minimal pleomorphism and single prominent nucleoli. Mitotic activity was variable. In general the cytoplasm was moderately abundant, eosinophilic, and granular, but many of the solid tumors had cells with scanty cytoplasm. Characteristic periodic acid-Schiffpositive, diastase-resistant cytoplasmic granules were demonstrated in >90% of the cases, and the butyrate esterase histochemical stain for lipase activity was positive in 73%. Immunohistochemically, there was positivity for trypsin in 100% of the cases, for lipase in 77%, for chymotrypsin in 38%, and for amylase in 31%. A minor endocrine component was recognized with antibodies against chromogranin or islet cell hormones in 42% of the tumors. Ultrastructurally, exocrine secretory features were present, with polarized cells showing microvillilined lumina, abundant rough endoplasmic reticulum, and 125-1,000-nm zymogen-like granules. In addition, many cases showed pleomorphic electron-dense granules measuring up to 3,500 nm and containing fibrillary internal structures. Follow-up information was available in 88% of the cases. Half of the patients had metastatic disease at presentation and an additional 23% subsequently developed metastases, which were usually restricted to the regional lymph nodes and liver. The mean survival for all cases was 18 months, with 1- and 3-year survivals of 57 and 26%, respectively. Patients presenting before age 60 years survived nearly twice as long as older patients did. Stage also influenced prognosis, whereas the histologic subtype of the tumors and the location within the pancreas correlated only weakly with survival.

Mucinous cystic neoplasm (mucinous cystadenocarcinoma of low-grade malignant potential) of the pancreas : a clinicopathologic study of 130 cases

Mucinous cystic neoplasms (MCNs) of the pancreas are uncommon tumors. The classification and biologic potential of these neoplasms remain the subject of controversy. Attempts to classify these tumors in a similar manner to ovarian MCNs remains controversial, as even histologically benign-appearing pancreatic MCNs metastasize and are lethal. One hundred thirty cases of MCNs were identified in the files of the Endocrine Pathology Tumor Registry of the Armed Forces Institute of Pathology from the years 1979 to 1993. The pathologic features, including hematoxylin and eosin staining, histochemistry, immunohistochemistry (IHC), cell cycle analysis, and K-ras oncogene determination were reviewed. These findings were correlated with the clinical follow-up obtained in all cases. There were 130 women, aged 20-95 years (mean age at the outset, 44.6 years). The patients had vague abdominal pain, fullness, or abdominal masses. More than 95% of the tumors were in the pancreatic tail or body and were predominantly multilocular. The tumors ranged in size from 1.5 to 36 cm in greatest dimension, with the average tumor measuring >10 cm. A spectrum of histomorphologic changes were present within the same case and from case to case. A single layer of bland-appearing, sialomucin-producing columnar epithelium lining the cyst wall would abruptly change to a complex papillary architecture, with and without cytologic atypia, and with and without stromal invasion. Ovarian-type stroma was a characteristic and requisite feature. Focal sclerotic hyalinization of the stroma was noted. This ovarian-type stroma reacted with vimentin, smooth muscle actin, progesterone, or estrogen receptors by IHC analysis. There was no specific or unique epithelial IHC. K-ras mutations by sequence analysis were wild type in all 52 cases tested. Ninety percent of patients were alive or had died without evidence of disease (average follow-up 9.5 years), irrespective of histologic appearance; 3.8% were alive with recurrent disease (average 10 years after diagnosis); and 6.2% died of disseminated disease (average 2.5 years from diagnosis). Irrespective of the histologic appearance of the epithelial component, with or without stromal invasion, pancreatic MCNs should all be considered as mucinous cystadenocarcinomas of low-grade malignant potential. Pancreatic MCNs cannot be reliably or reproducibly separated into benign, borderline, or malignant categories.

Intraductal oncocytic papillary neoplasms of the pancreas

We describe the clinical and pathologic features of 11 intraductal oncocytic papillary neoplasms of the pancreas, a hitherto unrecognized tumor. The patients were six men and five women, and most of the tumors were in the head (head: body/tail = 8:3). The mean patient age was 62 (range, 39-78), and the average tumor size was 6 cm. Grossly the tumors exhibited mucin-filled cysts containing nodular papillary projections. Dilated ducts communicating with the main tumor were sometimes noted. Microscopically the cystic structures appeared to represent dilated ducts containing intraductal tumor. The tumors were characterized by variably complex, arborizing papillary structures. The papillae had thin, delicate fibrovascular cores with focal myxoid changes and were lined by stratified oncocytic cells. Goblet cells and intra-epithelial mucin-containing lumina were present, the latter resulting in a characteristic cribriform pattern. The exuberance of the epithelial proliferation varied from case to case and between different regions within individual tumors; solid sheets of cells were often identified. Although the degree of cytologic atypia was not generally severe, the complexity of the architecture justified a designation of intraductal oncocytic papillary carcinoma in 10 of the 11 cases. In nine cases the tumor was entirely intraductal; one case exhibited focal microinvasion and another showed widespread invasive carcinoma, the invasive elements appearing cytologically similar to the intraductal papillary components. The oncocytic cells stained positively with phosphotungstic acid hematoxylin and Novelli stains. Immunohistochemically, all cases stained positively for B72.3, and five cases showed focal, weak luminal membrane staining for carcinoembryonic antigen. Ultrastructurally many of the cells were packed with mitochondria, and mucin was also identified. Seven patients were alive and free of tumor from 1 month to 3 years (average, 1 year) after resection. Two patients died postoperatively. The remaining two patients died with no evidence of disease at 2.5 and 5 years, the latter following a recurrence at 2.5 years. We conclude that intraductal oncocytic papillary neoplasm is a distinctive pancreatic tumor that is usually intraductal but may develop invasive carcinoma and should be treated with complete resection.

Interobserver and Intraobserver Variation Among Experts in the Diagnosis of Thyroid Follicular Lesions With Borderline Nuclear Features of Papillary Carcinoma

Distinguishing follicular variant of papillary carcinoma (FVPC) from follicular adenoma and follicular carcinoma can be difficult if nuclear features of papillary carcinoma are not well developed or only focally present. We assessed interobserver and intraobserver agreement among 6 thyroid experts by using 15 cases in which original pathologists suspected FVPC. There was unanimous expert agreement in diagnosing FVPC in only 2 cases (13%) and majority agreement in 6 cases (40%). Unanimous agreement on benign and malignant diagnoses was seen in 4 cases (27%) and majority agreement on malignancy in 8 cases (53%). Intraobserver agreement ranged from 17% to 100%. Histologic features considered most helpful in diagnosing FVPC were nuclear clearing, nuclear grooves, nuclear overlapping and crowding, nuclear membrane irregularity, and nuclear enlargement. This considerable interobserver and intraobserver variability in the diagnosis of FVPC seems to result from lack of agreement on the minimal criteria needed to diagnose FVPC, even among experts.

Adrenal cortical neoplasms in the pediatric population: a clinicopathologic and immunophenotypic analysis of 83 patients.

Adrenal cortical neoplasms in pediatric patients (<20 years) are rare. The clinical manifestations and biologic behavior of these lesions can be quite distinct from their histologically similar counterparts in the adult population, making pathologic criteria for distinguishing benign from malignant tumors equivocal. We undertook a study of 83 adrenal cortical neoplasms to determine if adult clinical and histologic features can be applied to pediatric patients in an outcome-based analysis. Most of the patients (50 girls and 33 boys) presented with hormone-related symptoms present for a mean of 6.8 months. The tumors ranged in size from 2 to 20 cm (mean 8.8 cm). Histologic parameters examined included capsular and/or vascular invasion, extraadrenal soft tissue extension, growth pattern, cellularity, necrosis, cytoplasmic eosinophilia, nuclear pleomorphism, nuclear-to-cytoplasmic ratio, prominent nucleoli, mitotic figures, atypical mitotic figures, bands of fibrosis, and calcifications. Immunophenotypically, there was reactivity with inhibin, vimentin, CK5, and focally with p53 and Ki-67. All patients underwent adrenalectomy, and 20 patients received adjuvant therapy. All patients with tumors classified as adenomas (n = 9) were alive, without evidence of disease (mean 14.7 years), whereas 21 patients with carcinomas had died with disease (mean 2.4 years). Only 31% of histologically malignant tumors behaved in a clinically malignant fashion. Features associated with an increased probability of a malignant clinical behavior included tumor weight (>400 g), tumor size (>10.5 cm), vena cava invasion, capsular and/or vascular invasion, extension into periadrenal soft tissue, confluent necrosis, severe nuclear atypia, >15 mitotic figures/20 high power fields, and the presence of atypical mitotic figures. Vena cava invasion, necrosis, and increased mitotic activity (>15 mitotic figures/20 high power fields) independently suggest malignant clinical behavior in multivariate analysis.

Pancreatoblastoma. A clinicopathologic study and review of the literature.

Pancreatoblastoma is a rare pancreatic tumor with a distinctive histologic appearance that generally affects infants and young children. We have studied 14 cases of pancreatoblastoma and reviewed 41 previously reported examples. Nine of our cases occurred in children (from newborn to 4 years old; mean, 2.4), and five affected adults (from 19 to 56 years old; mean, 40). There were 8 male cases and 6 female cases. Most patients presented with incidental abdominal masses, although pain, weight loss, and obstructive jaundice were present, but rarely. The tumors were very cellular microscopically, with cytologically uniform epithelial cells arranged in sheets and nests. Well-formed acinar structures were a consistent feature, and several cases contained ectatic ductular formations, rarely exhibiting intracellular mucin. Consistently present were squamoid corpuscles: circumscribed, whorled nests of plump spindle cells with a squamous appearance and occasional keratinization. The stroma was moderate to abundant and frequently quite cellular (especially in the pediatric cases). By immunohistochemistry, the tumors exhibited acinar, endocrine, and ductal differentiation, with positivity for pancreatic enzymes (100%), endocrine markers (82%), and carcinoembryonic antigen (85%). Ultrastructural examination most commonly revealed acinar differentiation, although mucigen granules and neurosecretory granules were also occasionally found. The behavior was variable: 36% of patients developed metastases, especially to the liver. The adult patients did poorly: three of five died of tumor (mean survival, 18 months), and two were alive at 5 and 15 months, respectively. In contrast, five of the six evaluable pediatric patients were alive from 22 months to 22 years after diagnosis, and only one died of tumor after 16 months. Good responses to chemotherapy were noted in the pediatric group.

Adenosquamous Carcinoma Of The Pancreas: A Clinicopathologic Series Of 25 Cases

Background: Adenosquamous carcinoma is a rare aggressive subtype of pancreatic adenocarcinoma. We describe the clinical, pathologic, and molecular characteristics of 25 of these lesions, the largest series to date. Methods: Twenty-five cases of adenosquamous carcinoma of the pancreas diagnosed between 1961 and 1994 were retrieved from the files of the Endocrine Registry of the Armed Forces Institute of Pathology. Histologic features were reviewed, histochemical, immunohistochemical, and molecular (k-ras) studies were performed, and patient follow-up was obtained. Results: The patients included 17 men and eight women, aged 28 to 82 years (mean, 65.4 y). The patients usually experienced weight loss (n = 17) or painless jaundice (n = 11), while also presenting with other abdominal symptoms. The tumors affected the head most frequently (n = 17), followed by the tail (n = 9) or body (n = 4). Five cases involved more than one anatomic region of the pancreas. Microscopically, all tumors demonstrated dual differentiation toward adenocarcinoma and squamous cell carcinoma. All cases tested were immunoreactive with keratin (AE1:AE3 and CK1), whereas other keratin markers were variably expressed: CK5/6 (88%), CK7 (68%), Cam5.2 (41%), and CK20(26%). CA-19–9 (84%) and CEA (74%) were positive in the majority of the cases. K-ras oncogene mutations were identified in seven of 13 cases. All patients died from their disease an average of 5.8 months after diagnosis (range, 1 to 33 months). Conclusions: Adenosquamous carcinoma of the pancreas represents a distinct clinical and pathologic entity, demonstrating the expected immunoprofile and k-ras oncogene mutation of a ductal origin, with a worse prognosis than ductal adenocarcinoma.

Epithelioid angiosarcoma of the adrenal glands. A clinicopathologic study of nine cases with a discussion of the implications of finding "epithelial-specific" markers.

Adrenal epithelioid angiosarcomas (AEA) are rare neoplasms. We report the clinicopathologic features of nine cases of AEA. AEA occurred most frequently in the sixth and seventh decades of life (age range, 45–85 years; median, 60); five cases occurred in men and four in women. Presenting symptoms included abdominal mass with or without pain, weight loss, fever, and weakness. Two cases were asymptomatic; one was discovered during evaluation for other disease(s) and the other at autopsy. All neoplasms were nonfunctioning. Radiographic evaluation demonstrated suprarenal or retroperitoneal neoplasms ranging in size from 6 to 10 cm in greatest dimension. Histologically, the neoplasms were invasive, predominantly arranged in solid sheets or nests, and composed of epithelioid cells. Endothelial cell differentiation was suggested by the transition areas between dilated anastomotic vascular spaces and the sheet-like growth, the cytomorphologic similarity between the endothelial cells lining the discernible vascular spaces and those seen in the solid foci, and the presence of intracy-toplasmic vacuolization occasionally containing red blood cells. Endothelial derivation was confirmed by immunohistochemistry including Factor VIH-related antigen (FVIII), CD-34 (hematopoetic progenitor cell antigen), and/or Ulex europaeus agglutinin-1 lectin immunoreactivity (UEA-1) and by ultrastructural findings, including rod-shaped microtubulated bodies and intra-cytoplasmic lumen formation. In addition, cytokeratin reactivity was seen in seven cases, and B72.3 (tumor-associated glycoprotein-72) reactivity was seen in six. Surgical resection was the treatment of choice, occasionally supplemented by chemotherapy. Three patients are presently alive, free of disease, at 13, 11, and 6 years following diagnosis. Three died with metastatic AEA of the lung, and three died of unrelated causes.

A clinicopathologic and immunohistochemical study of ten pancreatic lymphangiomas and a review of the literature

Pancreatic lymphangiomas are rare benign tumors, of which only a few cases have been reported in the literature. In this study, the authors present a series of primary pancreatic lymphangiomas.

Comparative genomic hybridization analysis of human parathyroid tumors.

Primary hyperparathyroidism is characterized by hypercalcemia and elevated parathyroid hormone levels. It can be caused by overactivity of one (adenoma or carcinoma) or more (hyperplasia or multiple adenoma) parathyroid glands. Parathyroid adenoma and hyperplasia are usually mono- or oligoclonal neoplasms. To establish whether parathyroid cancer has a genetic composition distinct from parathyroid adenoma, we analyzed 10 adenoma and 10 carcinoma cases by comparative genomic hybridization (CGH). Results show clear differences between the constitution of adenoma and carcinoma genomic DNA. The most frequent genomic alterations in adenoma included deletions on chromosomes 11, 17 (5 of 10 cases), and 22 (7 of 10 cases). In parathyroid carcinoma, frequent chromosomal deletions were on chromosome arm 1p (4 of 10 cases) and chromosome 17 (3 of 10 cases), and gains were on chromosome 5 (3 of 10 cases). Our data indicate that different genetic changes could contribute to the development of parathyroid adenoma and carcinoma; genomic losses predominate in adenoma, and gains along with some losses are found in carcinoma. Furthermore, the CGH results implicate several chromosomal regions that may harbor genes that could be potentially involved in the development of parathyroid adenoma and carcinoma.