Primary hepatic carcinoid tumor. An electron microscopic and immunohistochemical study

HER-2-positive primary neuroendocrine neoplasms of the breast with signet ring feature: A case report and review of literature

Background

Primary neuroendocrine neoplasm of the breast (BNEN) is an uncommon breast neoplasm, and in most cases, it presents as hormone receptors positive and HER-2 negative. Moreover, in neuroendocrine neoplasms (NENs), the signet ring feature is a rare morphological subtype, and only a few cases have been reported. Here, we report the case of a primary breast neuroendocrine neoplasm with an unusual signet ring cell appearance in this paper. The documentation of this case, combined with a review of the literature, may add to existing knowledge about the outcome and management of this rare tumor.

Methods

In the present review, we describe a unique case of HER-2-positive primary BNEN with a signet ring feature that has not been reported in English. Additionally, we performed a literature search of the PubMed and Web of Science databases and calculated statistics for clinical data and follow-up.

Results

Our literature search, excluding non-English literature, identified 15 articles with data from 24 cases, including ours. The mean age was 51.25 years (range, 30-79 years), and there were 13 male patients (54%) and 11 female patients (46%). Of the 24 cases, some cases (11/24) were associated with lymph node metastases, a few cases (6/24) had distant metastasis, and the vast majority of cases (23/24) occurred in the digestive system. Primary hepatic signet ring cell neuroendocrine tumor showed slow progression and good prognosis. Lymph node involvement was identified in one of eight (12.5%) documented cases, and one of eight (12.5%) reported cases presented with distant metastatic disease. However, the prognosis of neuroendocrine tumors with signet ring cells in the pancreas and stomach was poor. Lymph node involvement was identified in 9 of 15 (60%) documented cases, and 5 of 15 (33.3%) reported cases presented with distant metastatic disease.

Conclusion

NENs with a signet ring feature is uncommon, and this is the first case report of its occurrence in the breast. Current knowledge is limited to anecdotal experience based on case reports and small case series. We provide a literature review to summarize knowledge about this rare entity.

Primary multifocal cystic signet ring neuroendocrine tumor of liver: a case report

Primary signet ring neuroendocrine tumors of the liver are extremely rare tumors. Morphologically, they mimic signet ring cell adenocarcinomas; however, the absence of mucin by special stains and the expression of neuroendocrine markers help to diagnose these tumors. We herein report a case of a 47-year-old female who presented with multiple solid and cystic lesions in both liver lobes, which were initially suggested to be biliary cystadenocarcinoma on imaging. Liver biopsy of the lesion revealed the presence of a signet ring neoplasm with diffuse expression of synaptophysin and pan-cytokeratin. The case was subsequently diagnosed as a primary hepatic signet ring neuroendocrine tumor. The patient was offered 3 cycles of chemotherapy and is well preserved after 14 months of diagnosis. Although this is an extremely rare entity, its possibility should be considered in the differential diagnosis of neoplasms characterized by signet ring cell morphology.

Primary hepatic neuroendocrine neoplasm: Long-time surgical outcome and prognosis

Primary hepatic neuroendocrine neoplasms (PHNENs) represent a kind of rare liver tumor and its clinical features and prognosis remain unclear. This study aims to reveal the long-term therapeutic outcome of PHNEN and to present its prognostic feature.A retrospective designed, single-center study containing 22 patients with PHNENs receiving surgical resections was done. Clinical data were reviewed and long-term follow-up was updated. Survival analysis was tried to find the prognostic factors.Nine patients recurred (recurrence rate = 40.9%) and 6 patients died on the disease. The actual 1-, 3-, and 5-year recurrence-free survival rate were 86.4%, 63.6%, and 52.9%, respectively. The 1-, 3-, and 5-year overall survival rate were 95.5%, 81.8%, and 64.7%, respectively. Median overall survival for group G1, G2, and G3 were 69, 67, and 42 months, respectively.Patients with PHNEN can have a long survival after radical surgical resection, especially when the tumor proliferative grade exhibits lower (G1/2).

Long term recurrence in primary liver neuroendocrine tumor: Report of a single case and review of literature

Primary liver neuroendocrine tumors (PLNETs) are rare tumors of the liver. They share some common characteristics with neuroendocrine tumors (NETs) of the extrahepatic bile ducts, such as slow rise, hormonal, and histological features. Nevertheless, they possess some peculiarities and the major feature is the difference in the metastatic potential between PLNETs and NETs. PLNETs have less metastatic potential compared with NETs, which is the main factor based on which differential diagnosis between the two groups is achieved. There exists few reports disease's long-term outcome, especially about the recurrences management. We report the case of a 52-year-old woman admitted to hospital for jaundice and presence of liver mass. She underwent extended right hepatectomy and subsequently, PLNET was revealed. After 9 years, a new mass was discovered in the remnant liver, far from the resection line, and was surgically removed. Histological examination confirmed a PLNET recurrence. The patient is alive and doing well after a year of surgery. We conducted a review of the literature on recurrent PLNETS. Five papers followed our inclusion criteria and included 10 patients. Clinical presentation was mostly nonspecific in included cases and no carcinoid syndrome was reported. Median overall survival and median disease-free survival periods were 22 and 5 months, respectively. The primary disease was treated with surgical resection in all the included cases and recurrent diseases were mostly treated with non-surgical techniques (mainly transarterial chemoembolization). In conclusion, more studies should be conducted in order to have significant data about this uncommon neoplasm. Finally, considering the lack of data on long-term outcome, a long and accurate follow-up should be considered.

Neuroendocrine neoplasms of liver - A 5-year retrospective clinico-pathological study applying World Health Organization 2010 classification

AIM

To study the clinicopathological characteristics of neuroendocrine neoplasms (NEN) on liver samples and apply World Health Organization (WHO) 2010 grading of gastroenteropancreatic (GEP) NEN.

METHODS

Clinicopathological features of 79 cases of NEN of the liver diagnosed between January 2011 to December 2015 were analyzed. WHO 2010 classification of GEP NEN was applied and the tumors were graded as G1, G2 or G3. Two more categories, D1/2 (discordant 1/2) and D2/3 (discordant 2/3) were also applied. The D1/2 grade tumors had a mitotic count of G1 and Ki-67 index of G2. The D2/3 tumors had a mitotic count of G2 and Ki-67 index of G3. The follow up details which were available till the end of the study period (December 2015) were collected.

RESULTS

Of the 79 tumors, 16 each were G1 and G2, and 18 were G3 tumors. Of the remaining 29 tumors, 13 were assigned to D1/2 and 16 were D2/3 grade. Male preponderance was noted in all tumors except for G2 neoplasms, which showed a slight female predilection. The median age at presentation was 47 years (range 10-82 years). The most common presentation was abdominal pain (81%). Pancreas (49%) was the most common site of primary followed by gastrointestinal tract (24.4%) and lungs (18%). Radiologically, 87% of the patients had multiple liver lesions. Histopathologically, necrosis was seen in only D2/3 and G3 tumors. Microvascular invasion was seen in all grades. Metastasis occurred in all grades of primary NEN and the grades of the metastatic tumors and their corresponding primary tumors were similar in 67% of the cases. Of the 79 patients, 36 had at least one follow up visit with a median duration of follow up of 8.5 mo (range: 1-50 mo). This study did not show any impact of the grade of tumor on the short term clinical outcome of these patients.

CONCLUSION

Liver biopsy is an important tool for clinicopathological characterization and grading of NEN, especially when the primary is not identified. Eighty-seven percent of the patients had multifocal liver lesions irrespective of the WHO grade, indicating a higher stage of disease at presentation. Follow up duration was inadequate to derive any meaningful conclusion on long term outcome in our study patients.

Neuroendocrine differentiation in embryonal type hepatoblastoma

Hepatoblastoma, a malignant tumor which arises occasionally in older children but very rarely in adults, exhibits divergent differentiation with embryonal cells, fetal hepatocytes and immature elements. This report describes an embryonal type hepatoblastoma with neuroendocrine differentiation in a 16-year-old patient, which was diagnosed postoperatively. Clinical and radiologic work-up failed to reveal a primary gastrointestinal malignancy and no primary lesions were detected in any other organ. This feature of hepatoblastoma is considered to be a multidirectional differentiation of the small epithelial or stem cells of the liver. At 2-year follow up, the patient remains symptom-free, with normal laboratory and diagnostic imaging studies, and no recurrent or metastatic disease identified.

Primary Hepatic Neuroendocrine Tumor: What Do We Know Now?

Primary hepatic neuroendocrine tumors (PHNETs) are rear neoplasm. Diagnosis is an evolution, and requires a systematic clinical exclusion with histological confirmation. Treatment is surgical with excellent prognosis, and a long-term follow-up is required due to high tumor recurring rate. Knowledge from this species of tumor remains limited due to paucity of cases. This article elaborates the key features, diagnosis algorithm, current management, other treatment options and extensive review of literature on this rear tumor.

[Primary neuroendocrine carcinoma of the liver. From carcinoid tumor to small-cell hepatic carcinoma: case reports and review of the literature]

Primary hepatic neuroendocrine tumors are rare neoplasms. While primary hepatic carcinoid tumors (PHCT) are well-differentiated tumors, primary hepatic small-cell carcinomas (PHSCC) represent the poorly differentiated end of the spectrum of neuroendocrine carcinomas. The first patient, suffering from PHCT, has had a follow-up for 32 years and is still alive. Within this time, the tumor relapsed 4 times with unchanged histology and immunohistochemistry features. The second patient suffered from small-cell carcinoma of the liver. There were no risk factors for a hepatocellular carcinoma. An extensive preoperative and postoperative diagnostic investigation could rule out an extrahepatic primary site. Immunohistochemically the tumor was negative for Hepar-1, AFP, TTF1 and CDX2 but reacted positively with CD56 and sporadically with the keratins 8, 18 and 20. A neuroendocrine PHSCC was diagnosed. After neoadjuvant cytostatic treatment the carcinoma was completely extirpated and 18 months after treatment the patient is healthy.PHCT and PHSCC have to be clearly separated from hepatocellular and cholangiocellular carcinomas. Exclusion of an extrahepatic primary site requires an accurate and synoptic analysis of clinical, radiologic and pathologic findings. Surgical resection is the treatment of choice.

Primary Hepatic Carcinoid Tumours: Clinical Features with an Emphasis on Carcinoid Syndrome and Recurrence

This study sought to determine the clinical profiles and optimal management of primary hepatic carcinoid tumours. The clinical features of nine Chinese patients and 64 patients reported in the English-language literature were characterized. Recurrence rate and survival analysis were performed with the Kaplan–Meier method. The impact of surgical resection and post-operative recurrence on survival was determined by means of the log-rank test. Carcinoid syndrome complicated 10 cases (14%). Sixty-two patients (85%) underwent surgical resection. Actuarial 5-and 10-year survival rates for resected patients were 80% and 75%, respectively. Twelve patients experienced recurrences: the recurrence rate at 5 years post-operatively was 26%. All patients with resectable recurrent disease achieved good long-term survival and no significant relationship was found between recurrence and survival. Owing to the high incidence of recurrence, long-term follow-up is necessary and it is recommended that recurrent cases should be managed with judicious surgical resection.

Surgical treatment of primary neuroendocrine tumors of the liver

Primary neuroendocrine tumor (NET) of the liver is a very rare neoplasm, requiring strict exclusion of possible extrahepatic primary sites for its diagnosis. We have analyzed our clinical experience of eight patients with hepatic primary NET. From January 1997 to December 2006, eight patients with a mean age of 50.4 +/- 9.5 years underwent liver resection for primary hepatic NET. Seven patients underwent preoperative liver biopsies, which correctly diagnosed NET in four. Of the eight patients, six underwent R0 and two underwent R1 resection. Diagnosis of hepatic primary NET was confirmed immunohistochemically and by the absence of extrahepatic primary sites. All tumors were single lesions, of mean size 8.6 +/- 5.7 cm, and all showed positive staining for synaptophysin and chromogranin. During a mean follow-up of 34.0 +/- 39.7 months, three patients died of multiple liver metastases after tumor recurrence, whereas the other five remain alive to date, making the 5-year recurrence rate 40% and the 5-year survival rate 56.3%. Univariate analysis showed that Ki67 proliferative index was a risk factor for tumor recurrence. In conclusion, although primary hepatic NET is very rare, it should be distinguished from other liver neoplasms. The mainstay of treatment is curative liver resection.

Primary hepatic neuroendocrine carcinoma: an underdiagnosed entity

Primary hepatic neuroendocrine tumors are rare. We report a case of a primary neuroendocrine carcinoma of the liver with a review of the literature. In earlier reports, all of these tumors were named hepatic carcinoids. We now recognize that they belong to a heterogeneous group of neoplasms, with microscopic appearance not necessarily predictive of biologic behavior. To our knowledge, only 55 cases have been reported in the English literature. This entity has probably been underreported because of the assumption that it represents a metastatic lesion. A search for an occult primary neuroendocrine tumor outside the liver must always be pursued.

Liver resection for primary hepatic neuroendocrine tumours: report of three cases and review of the literature

Primary neuroendocrine tumours are rare especially in the liver, which is more often site of metastatic tumours. We report three cases of primary hepatic neuroendocrine tumours, which underwent hepatic resection. Review of the diagnostic and therapeutic approaches to these tumours are discussed.

Recurrence of primary hepatic carcinoid tumor in the remnant liver 13 yr after resection

We report here a case of primary hepatic carcinoid tumor (PHCT) recurring in the remnant liver 13 yr and 10 mo after first resection. A 70-yr-old man developed four hypervascular tumors in the liver in December 2003. He had undergone curative left-lobe hepatectomy for PHCT in February 1990. Histopathological examination of the tumor biopsy specimen showed that the tumor was composed of uniform round-to-oval cells with solid arrangement and the tumor cells stained positive for chromogranin A, synaptophysin, and neuron-specific enolase. We diagnosed this case as an intrahepatic metastasis of PHCT with a long latency period, based on the fact that no primary site of carcinoid tumor could be found despite intensive examination and the immunohistochemical findings of the resected tumors were essentially same as those of PHCT in 1990. Although PHCT is reported to have a more favorable prognosis than other hepatic cancer or metastatic carcinoid tumor in the liver, long-term observation is recommended.

Primary hepatic carcinoid tumor: dynamic CT findings

Most carcinoid tumors involve the gastrointestinal tract or respiratory system. Primary hepatic carcinoid tumor is a rare entity. A 46-year-old woman presented with abdominal pain, vomiting, and diarrhea. She was diagnosed with primary hepatic carcinoid tumor based on radiologic and laboratory findings, namely a mass in the fifth segment of the liver and markedly elevated levels of 5-hydroxyindole acetic acid in the urine. Histologic and immunohistochemical findings of the resected liver segment showed a malignant carcinoid tumor of the liver. This case is of interest because of the rarity of this neoplasm. This report describes the case and reviews the clinical features, radiologic findings, and treatment in previously reported cases.

Long-term survival after resection for primary hepatic carcinoid tumor

BACKGROUND

Primary hepatic carcinoid tumors (PHCTs) are extremely rare, and fewer than 50 cases have been reported in the English-language literature. We report a patient with a PHCT and review the cases in the literature.

METHODS

Our patient presented with symptoms and underwent liver resection for PHCT and regional lymph node metastasis. He underwent two more liver resections over the following 7 years for recurrent PHCT. Cases reported in the English-language literature were reviewed and survival analysis was performed with the Kaplan-Meier method. The survival impacts of age, gender, tumor foci, extrahepatic metastasis, unilobar versus bilobar disease, and type of preoperative treatment were determined by means of log-rank test.

RESULTS

Our patient has been free of symptoms for 14 years of follow-up and free of disease for 8 years of follow-up. Forty-eight cases of PHCT were found in the literature, and 92% of these patients underwent resection. Actuarial 5- and 10-year survival for all patients was 78% and 59%, respectively, whereas for resected patients, 10-year survival was 68%. The administration of preoperative chemotherapy, radiation therapy, or chemoembolization did not impact survival, nor did age, gender, presence of extrahepatic metastasis, number of tumors, or distribution of the tumor within the liver.

CONCLUSIONS

Resection is the treatment of choice for PHCT and has provided favorable outcomes. Resection for PHCT can be performed in most patients and offers long-term survival.

Hepatic resection and transplantation for primary carcinoid tumors of the liver

OBJECTIVE

To discuss the diagnosis and management of primary carcinoid tumors of the liver in light of our experience and a literature review.

SUMMARY BACKGROUND DATA

Carcinoid tumors of the liver are rare and pose a diagnostic and management dilemma. This series is the largest reported and the only one to include liver transplantation as a treatment option.

METHODS

Between March 1994 and May 2002, we treated 8 patients (4 male, 4 female) with primary hepatic carcinoid tumors. Carcinoid syndrome complicated only 1 of the cases. Treatment was by liver resection in 6 patients and orthotopic liver transplantation in 2.

RESULTS

The diagnosis was confirmed histologically with light microscopy and immunohistochemistry in the absence of an alternative primary site. Six patients remain alive and disease free after follow-up of more than 3 years: 39, 43, 45, 50, 50, and 95 months. Two patients are recently postoperative.

CONCLUSIONS

Active exclusion of an extrahepatic primary site is essential for the diagnosis of primary carcinoid of the liver. The mainstay of treatment should be liver resection, although liver transplantation may be considered in patients with widespread hepatic involvement. A radical surgical approach is warranted as this disease carries a better prognosis than for other primary hepatic tumors and for secondary hepatic carcinoids.

Primary hepatic carcinoid tumours

BACKGROUND

Carcinoid tumours of the liver are predominantly metastases from the gastrointestinal tract. Primary hepatic carcinoids are extremely rare.

DISCUSSION

In contrast to metastases, primary hepatic carcinoids are usually solitary and resectable. It is important that these tumours are differentiated from metastases. Complete surgical resection should be contemplated and is generally curative.

Bone marrow infiltrate by a poorly differentiated neuroendocrine carcinoma

We report a rare case of bone marrow infiltrate by a neuroendocrine carcinoma. The patient was a 66-year-old man who presented with anemia and thrombocytopenia and with a leukoerythroblastic picture on blood films. A bone marrow biopsy revealed extensive tumor infiltrate with morphological and immunohistochemical features of neuroendocrine origin. There were also multiple nodular lesions in the liver, which showed the same pathology as that in the bone marrow. Since none of the lesions could be identified as the primary tumor, the patient was diagnosed to have a poorly differentiated neuroendocrine carcinoma of unknown primary site.

Primary neuroendocrine carcinoma of the liver: an autopsy case

An autopsy case of primary hepatic neuroendocrine carcinoma is described. A 72-year-old man had a large tumor mass measuring 22 cm in its greatest diameter and localized to the right, left and caudal lobes of the non-cirrhotic liver. Microscopically, the tumor was composed of middle-sized pleomorphic cells organized in ribbons or trabeculae, with scanty intersecting fibrous septae. Immunohistochemically, the tumor cells were positive for multikeratin C11, chromogranin A and synaptophysin. The patient also had metastases in the bone marrow. No alternative primary source of endocrine tumor was detected. The patient died 4 days after presentation.

Primary hepatic carcinoid in a renal transplant patient

There seems to be a world-wide increase in the incidence of tumors among immunosuppressed patients. Of 1350 renal allografts transplanted in the past 23 years at the Department of Transplantation and Surgery, 56 cases were malignant tumors. The case of a 58-year-old female patient is reported, with disseminated primary carcinoid in the liver detected 86 days after renal transplantation. According to the literature only 39 patients with primary liver carcinoids have been reported until 1997, but this is the first where the carcinoid developed in an immunosuppressed patient. The rapid progression of the carcinoid could be associated with the immunosuppression.

Aspiration cytodiagnosis of small cell malignancies found in fine needle aspirate (FNA) of the liver: an immunocytochemical study

In this study the features of small cell malignancies found in the liver by fine needle aspiration cytology (FNAC) and immunostains required for a diagnosis and differential diagnosis are presented. The material consisted of 197 fine needle aspirates which were performed under image guidance between January 1982 to October 1999. Of these, 30 were diagnosed as small cell malignancies. The age of patients ranged between 46 and 68 years. The aspirated material was examined using Papanicolaou-stained filter preparations and cell blocks, the latter stained with hematoxylin and eosin and a panel of immunoperoxidase stains. The diagnoses based on a correlation of relevant clinical history, cytohistological findings and immunostaining were: metastatic small cell anaplastic carcinoma of lung (n = 6); neuroendocrine tumour (n = 9); non-Hodgkin's lymphoma (n = 4); well-differentiated cholangiocarcinoma (n = 2); metastatic carcinoma of the prostate (n = 2); metastatic adenocarcinoma (n = 4) and metastatic carcinoma breast (n = 3). This study emphasizes the wide range of neoplasms that enter into the differential diagnosis of small cell malignancies found in the liver and a correlation of clinical, cytohistological and immunostaining findings which seem to be useful in suggesting a diagnosis.

Fine needle aspiration diagnosis of neuroendocrine tumors in the liver

Ten neuroendocrine tumors (NET) in the liver are presented, in which the diagnosis was made on fine needle aspiration cytology and cell blocks from the aspirate. In seven of the patients with liver metastasis, a biopsy-proven extrahepatic primary NET had been previously diagnosed, while in three patients no extrahepatic neoplasm could be identified, suggesting that the NET may have been a primary in the liver. Based on cytomorphological findings the cases were typed as either round cell type, spindle cell type or polygonal cell type. In all cases, immunopositivity for neuroendocrine markers provided reliable evidence of the cell of origin and distinguished them from well-differentiated hepatocellular carcinoma, adenocarcinomas and other neoplasms, which sometimes may present a diagnostic dilemma.

Hepatic carcinoid, hypercortisolism and hypokalaemia in a dog

A German Shepherd dog was diagnosed with periodic myopathy secondary to persistent hypokalaemia. Hormone analysis revealed excess cortisol secretion. A neuroendocrine carcinoma, thought to be a primary hepatic carcinoid, was detected in the liver. Ectopic adrenocorticotrophin hormone secretion was suspected as the cause of hypercortisolism and hypokalaemia, although this could not be confirmed by immunohistochemical staining.

Primary hepatic carcinoid and neuroendocrine carcinoma: clinicopathological and immunohistochemical study of five cases

Primary hepatic carcinoid and neuroendocrine carcinoma (NEC) are rare tumors. We experienced three carcinoids and two NEC originating in the liver during the past 25 years and attempted to elucidate the clinicopathological and immunohistochemical features of these tumors. The patients had no endocrine symptoms despite two of them having elevated plasma serotonin. Three of the five patients died of the tumor after operation with an average survival time of 20.6 months. All tumors were large (up to 26 cm in diameter), four of them solitary and one multinodular, and were not associated with liver cirrhosis. The carcinoid tumors showed insular, trabecular or glandular arrangement of argyrophilic cells, whereas in the NEC this histological pattern was distorted. Immunohistochemically the tumors showed expression of chromogranin A (all cases), chromogranin B (three cases), pancreastatin and chromostatin (four cases, respectively), prohormone convertase PC3 (three cases), carcinoembryonic antigen (CEA) and CA19-9 (two cases), cytokeratin 56 kDa (three cases), 160 kDa neurofilament (two cases) and neuron-specific enolase (two cases). Serotonin and glucagon were sporadically detected in two tumors. The most useful marker to confirm the diagnosis was chromogranin A, which was cleaved to pancreastatin and chromostatin in the tumor tissue, and was more reliable than other markers of neuroendocrine differentiation.

Diagnosis and differential diagnosis of small-cell lesions of the liver

The objective of this study was to evaluate the cytologic spectrum of small cell lesions of liver as diagnosed by fine-needle aspiration (FNA). Of 304 FNAs of liver that were performed in our institution between 1990 and 1994, 29 were classified as small-cell lesions. The final diagnoses were as follows: small-cell undifferentiated carcinoma (10), neuroendocrine carcinoma (9), cloacogenic carcinoma (1), Merkel-cell carcinoma (1), cholangiocarcinoma (1), metastatic adenocarcinoma (4), small-cell sarcoma (1), lymphoma (2). Relevant clinical history and immunocytochemistry were helpful in making the final diagnosis in some cases. The diagnosis and differential diagnosis of small cell lesions of the liver are discussed in detail in this report.

Hepatoblastoma in a dog

A hepatoblastoma was found in a 13-year-old female Maltese dog. Histologically, the tumor showed a wide trabecular pattern and was frequently accompanied with vascular lake formation. Tumor cells were positive for cytokeratin and neuron specific enolase, but negative for chromogranin. Electronmicroscopically, tumor cells were accompanied with continuous basement membrane and had poorly developed desmosomes. Sinusoidal endothelia had fenestration and were surrounded by myofibroblast-like cells. To the best of our knowledge, this paper is the first report of morphological studies on canine hepatoblastoma.

Histocytologic diagnosis of neuroendocrine tumors in the liver: a retrospective study of 23 cases

A series of 23 needle biopsies of neuroendocrine tumors occurring in the liver is described. Aspirate smears, core biopsies, and touch preparations were examined. Eighteen of the 23 patients had been previously diagnosed: 9 patients had been correctly identified as having a neuroendocrine tumor, and 9 patients had been originally misdiagnosed. Five of the patients in this series had no previously identified neoplasia. Immunohistochemical staining confirmed the neuroendocrine nature of the tumors in each of the cases. On the basis of cytomorphology, these cases were subtyped as either round cell type, spindle cell type, or polygonal cell type. The polygonal cell type of neuroendocrine tumor, as well as rare examples of the round cell type, demonstrated features similar to well-differentiated hepatocellular carcinoma and adenocarcinomas, and may present a diagnostic dilemma. Characteristic cytologic attributes of the polygonal cell type of neuroendocrine tumor which aid in its distinction from well-differentiated hepatocellular carcinoma include eccentrically located "plasmacytoid" nuclei and cellular discohesion. Findings on core needle biopsy which further identify the neuroendocrine tumors are thick fibrous stroma or small "nests" of tumor cells. The additional use of immunohistochemical staining provides reliable evidence of the cell of origin in confusing cases. Attention to these considerations will aid in the cytologic diagnosis of neuroendocrine tumors.

Primary carcinoid tumor of the liver: report of four resected cases including one with gastrin production

Four cases of primary hepatic carcinoid were identified during a retrospective study of liver resections for primary tumor. The cases included two adult males, one adult female, and a 9-year-old boy in whom gastrin levels were documented. The estimation of gastrin levels was prompted by symptoms suggestive of acid-peptic disease. One patient died postoperatively. The other three are alive and well at 3 years, 2 years, and at 1 year, respectively, after surgery, outcomes distinctly different from hepatocellular carcinomas. Diagnostic difficulties may be experienced in histologic assessment, and this may require recourse to immunohistochemistry and electron microscopy. Long-term follow-up and careful exclusion of a possible primary elsewhere are necessary for establishing the primary nature of liver carcinoids.

Primary hepatic carcinoid tumor

A case of primary carcinoid tumor arising in the liver of a 69 year old woman with no endocrine symptoms is reported. Histopathologically, the tumor was diagnosed initially as a hepatocellular carcinoma in the biopsy specimen, and was shown subsequently to be a carcinoid tumor, demonstrating diffuse positive staining with Grimelius method. Mucin stained with periodic acid-Schiff (PAS), alcian-blue, and mucicarmine, and was shown partially in the glandular structures. Immunohistochemically, most of the tumor cells stained positively for chromogranin-A, epithelial membrane antigen (EMA) and neuron specific enolase (NSE). Ultrastructural examination revealed electron-dense core granules, measuring 40-120 nm in diameter in some of the tumor cells. Intensive and careful searches pre- and post-operatively revealed no other primary source of tumor other than the liver. The patient was reported well with no symptoms 3 1/2 years after the operation. This case is considered to be a primary hepatic carcinoid tumor. The recent literature is reviewed, and the possible histogenesis of hepatic carcinoid tumor is discussed.

Primary hepatic neuroendocrine carcinoma in a child. Morphologic, immunocytochemical, and molecular biologic studies

BACKGROUND

Primary neuroendocrine tumor of the liver is uncommon, and virtually all reported patients with the tumor have been adults. Most of the tumors were carcinoids. The authors report an 8-year-old girl with primary hepatic neuroendocrine carcinoma.

METHODS

Histologic, ultrastructural, and immunocytochemical studies and Southern blot analysis of tumor N-myc DNA were performed in the patient.

RESULTS

Histologically, the tumor revealed a characteristic organoid pattern with a spectrum of differentiation varying from well-differentiated carcinoid-like areas to poorly differentiated pleomorphic areas. Ultrastructural features included neurosecretory granules and interdigitating cytoplasmic extensions. The tumor cells showed immunoreactivity to neuron-specific enolase (NSE), S-100 protein, chromogranin, and synaptophysin. No evidence of amplification of tumor N-myc DNA was present. However, the molecular weight of the tumor N-myc DNA (1.8 kb) was significantly lower than the normal control (from normal liver tissue) (2.0 kb).

CONCLUSIONS

This report documents the occurrence of primary hepatic neuroendocrine carcinoma in a child. Thorough studies and complete clinical evaluation are essential to the establishment of diagnosis. The result of N-myc DNA analysis probably is attributable to deletion of part of the tumor N-myc gene. The clinical implication of this finding is unknown, and additional investigation is warranted.

Ultrastructural and immunocytochemical study of a primary gastrinoma of the liver

A primary hepatic gastrinoma found in a 13-year-old boy was studied by light microscopy, immunohistochemistry, electron microscopy, and immunoelectron microscopy. Results were consistent with a neuroendocrine neoplasm with abundant gastrin-immunoreactive cells. Unlike all previously reported cases of primary hepatic neuroendocrine tumors, which have been endocrinologically asymptomatic, the patient had a Zollinger-Ellison syndrome apparently cured by surgical resection of the tumor.