Primary small cell carcinoma of the stomach

Metastatic Neoplasms Involving the Stomach

OBJECTIVES

Metastatic neoplasms involving the stomach are rare and diagnostically challenging if clinical history of malignancy is absent or unavailable. This study was designed to identify the tumors that most frequently metastasize to the stomach and the morphologic features that can provide clues to investigate the possibility of metastasis and predict the primary sites.

METHODS

All patients with metastatic neoplasms involving the stomach were included in the study. The H&E- and immunohistochemical-stained slides were reviewed, and all clinical, endoscopic, and radiologic information was recorded.

RESULTS

One hundred fifty patients, including 84 (56%) women and 66 (44%) men (mean age, 64 years), were identified. Gastric metastases were the initial presentation in 15% cases. Epithelial tumors (73.3%) comprised the largest group, followed by melanoma (20.6%), sarcomas (4%), germ cell tumors (1.3%), and hematolymphoid neoplasms (0.7%). Lobular breast carcinoma was the most common neoplasm overall in women, while in men, it was melanoma. Solid/diffuse growth pattern (75%) was more common compared with glandular morphology. The solid/diffuse category included lobular breast carcinoma (21.3%), melanoma (20.6%), and renal cell carcinoma (10.6%), while the glandular category was dominated by gynecologic serous carcinomas (7.3%) with papillary/micropapillary architecture.

CONCLUSIONS

Metastatic neoplasms should be considered in the differential diagnosis of gastric neoplasms, particularly those with a diffuse/solid growth pattern. Glandular neoplasms are difficult to differentiate from gastric primaries except for Müllerian neoplasms, which frequently show a papillary/micropapillary architecture.

Primary Gastric Small Cell Carcinoma (Presenting as Linitis Plastica) Diagnosed Using Endoscopic Ultrasound-Guided Biopsy: A Case Report

Small cell carcinomas are the most aggressive, highly malignant neuroendocrine tumors; among these, gastric small cell carcinoma (GSCC) is extremely rare. Here we report a case of a patient with primary GSCC, presenting as linitis plastic, who was diagnosed using endoscopic ultrasound (EUS)-guided biopsy. With undiagnosed linitis plastica, an 80-year-old woman was referred to our institution. Abdominal computed tomography revealed irregular wall thickening extending from the gastric body to the antrum. Endoscopy suspected to have Borrmann type IV advanced gastric cancer. EUS of the stomach showed diffuse submucosal thickening of the gastric wall, mainly the antrum. EUS-guided bite-on-bite biopsy confirmed the diagnosis of GSCC. In general, GSCC is difficult to diagnose and careful examination is necessary to determine the therapeutic strategy; however, EUS is particularly helpful in the differential diagnosis of a lesion presenting as linitis plastica.

Stage 1 small cell cancer of the vagina

This is the case of a 56-year-old white woman with a medical history significant for chronic obstructive pulmonary disease, migraine, hypertension, tobacco abuse and hypercholesterolaemia. Her surgical history is significant for total hysterectomy and bilateral salpingo-oophorectomy for diffuse endometriosis. The patient presented with a vaginal lesion. The biopsy was positive for primary vaginal small cell carcinoma and human papilloma virus (HPV). Initial staging positron emission tomography (PET) scan confirmed stage 1 disease. The patient was started on chemotherapy with cisplatin and etoposide for four cycles, followed by concurrent chemotherapy with cisplatin/taxol and radiation therapy.

Small cell carcinoma of the stomach: A report of two cases and a review of the literature

Primary small cell gastric carcinomas (SCGC) are rare tumors with an aggressive nature, characterized by early, widespread metastases and poor overall prognosis. SCGC shares similar clinicopathological and molecular characteristics with small cell lung carcinoma and is usually treated in a similar manner. Here, two cases of SCGC in young Caucasian male patients are presented. One patient had metastatic and the other locoregional disease. Multimodal treatment was applied in each case; the resulting survival time was 20.2 months in the patient with initially locoregional disease whereas the remains alive and disease-free 20 months after initial diagnosis. A review of the literature is also presented.

Long-Term Survival of a Patient with Metastatic Small-Cell Carcinoma of the Stomach Treated with Radiation Therapy

Small-cell carcinoma (SCC), or high-grade neuroendocrine carcinoma of the stomach, is a rare subtype of extra-pulmonary SCC which is almost invariably lethal. Gastric SCC often presents with local symptoms indistinguishable from other primary stomach cancers; however, both regional and distant spread are common at the initial presentation. Depending on symptoms and patient performance status, treatment typically consists of chemotherapy or resection followed by adjuvant chemotherapy, as even patients with limited stage gastric SCC likely have micrometastatic disease at the time of diagnosis. In this case report, we describe the long-term survival of a 75-year-old male with recurrent oligometastatic high-grade neuroendocrine carcinoma of the stomach treated with radiation therapy (RT) alone. He presented with abdominal pain and dyspepsia and was found to have a 6 cm locally invasive node-positive gastric SCC initially treated with extensive surgical resection. He was not a candidate for adjuvant chemotherapy, and surveillance imaging subsequently confirmed metachronous liver and local recurrences within 1 year after surgery, which were managed with stereotactic body RT and conventional radiation, respectively. An additional para-aortic nodal recurrence was treated with intensity-modulated radiotherapy 7 years after surgery with good response. He tolerated all RT courses without notable radiation-related toxicity and remains in complete remission 11 years after initial diagnosis.

Application of immunohistochemistry in gastrointestinal and liver neoplasms: new markers and evolving practice

CONTEXT

Diagnosis of primary gastrointestinal and liver neoplasms is usually straightforward. Immunohistochemistry is most helpful to differentiate metastatic carcinomas with morphologic similarity and to resolve tumors of unknown origin. Recently, several new markers highly sensitive and specific for primary liver and gastrointestinal tumors have been discovered. Their potential diagnostic application has not been widely appreciated by general practicing pathologists. In addition, a new trend in immunohistochemistry application has started, focusing on assessing predictive markers (such as human epidermal growth factor receptor 2) and mutation-specific markers (v-raf murine sarcoma viral oncogene homolog B V600E) to directly guide clinical management. Practicing pathologists need to be aware of and prepared for this evolving trend.

OBJECTIVES

To summarize the usefulness of several recently discovered immunohistochemical markers in the study of gastrointestinal and liver tumors; to suggest the most current and effective immunohistochemical panels addressing common diagnostic challenges for these tumors; to share practical experience and useful tips for human epidermal growth factor receptor 2 testing in gastric and gastroesophageal junction adenocarcinoma and v-raf murine sarcoma viral oncogene homolog B V600E immunohistochemistry in colorectal carcinoma.

DATA SOURCES

Sources include literature review, and authors' research data and practice experience. The cases illustrated are selected from the pathology archives of the Geisinger Medical Center (Danville, Pennsylvania).

CONCLUSIONS

Application of immunohistochemistry in gastrointestinal and liver tumors continues to evolve. New tumor-specific markers constantly emerge and help pathologists to further improve diagnostic accuracy. Assessment of predictive and prognostic markers by immunohistochemistry in routine pathologic diagnosis is a new trend and will greatly facilitate the advancement of personalized cancer therapy.

Neoadjuvant chemotherapy followed by D2 gastrectomy and esophagojejunal Roux-en-Y anastomosis in gastric small cell carcinoma: A case report

A 60-year-old male was referred to Nanjing Drum-Tower Hospital (Nanjing, Jiangsu, China) due to the presence of gastric carcinoma. A biopsy was performed under an electronic gastroscope and the pathological analysis resulted in the diagnosis of gastric small cell carcinoma (GSCC). The mass had invaded the liver and the pancreas according to an enhanced computed tomography scan, thus current surgical methods were considered to be of high risk and highly challenging. Following four cycles of neoadjuvant chemotherapy with irinotecan (200 mg, days 1, 21, 41 and 61) and oxaliplatin (120 mg, days, 1, 21, 41 and 61) the patient underwent a D2 gastrectomy and an esophagojejunal Roux-en-Y anastomosis, followed by adjuvant chemotherapy. The patient experienced survival without progression in the 8-month follow-up. To the best of our knowledge, this is one of few cases of GSCC treated with the combination of neoadjuvant chemotherapy, surgery and adjuvant chemotherapy.

Successful combination chemotherapy with irinotecan hydrochloride and cisplatin for primary gastric small cell carcinoma: report of a case

Primary gastric small cell carcinoma is a rare and aggressive malignant disease with a poor prognosis that was first reported in 1976 by Matsusaka et al. The incidence is very low and the clinicopathological features are similar to those of small cell lung carcinoma.

We herein report a case of successful treatment by combination chemotherapy consisting of irinotecan hydrochloride and cisplatin for primary gastric small cell carcinoma. The patient was a 71-year-old male who was admitted to a local hospital with anemia. Gastrointestinal endoscopy revealed the presence of advanced gastric carcinoma at the upper region of the stomach. The patient underwent surgery, and the pathological diagnosis was small cell carcinoma due to the presence of the typical features of small round cells with scant cytoplasm that were positive for synaptophysin and chromogranin A in the resected specimen. The patient underwent subsequent combination chemotherapy, which provided him with over 1 year of survival and a good quality of life. We also present a review of the literature regarding chemotherapy for primary gastric small cell carcinoma.

Limited stage small cell carcinoma of the gastrointestinal tract: a clinicopathologic and prognostic analysis of 27 cases

Small cell carcinoma of the gastrointestinal tract is a rare and aggressive neuroendocrine tumor. This study aims to analyze the clinical characteristics and potential prognostic factors for patients with limited stage small cell carcinoma of the gastrointestinal tract. The records of 27 patients with limited stage small cell carcinoma of the gastrointestinal tract, who all received surgery with lymphadenectomy, were retrieved and analyzed retrospectively. The median age of patients was 60 years old (range 38–79). The primary locations of tumor were the esophagus (74.1%) and stomach (14.8%). The rate of preoperative accurate diagnosis (16.7%) was low for small cell carcinoma of the esophagus and stomach. 40.7% of all the patients had regional lymph node metastases. Five patients underwent surgery alone, and the other 22 were treated with surgery + postoperative chemotherapy. All patients had disease progression or recurrence. The overall median survival time was 10 months and the 1-year survival rate was 37.0%. Patients who received postoperative chemotherapy had a median survival time of 12 months, which was superior to the 5-month survival of for those who only had surgery (P<0.0001). TNM stage (P=0.02) and postoperative chemotherapy (P<0.0001) were considered as two prognostic factors in uni-variate analysis. Postoperative chemotherapy was a significant independent prognostic factor in multivariate analysis (P=0.01). The prognosis for patients with limited stage small cell carcinoma of the gastrointestinal tract remains dismal, however, postoperative chemotherapy may have the potential to improve the outcome for these patients.

Neuroendocrine carcinoma of the stomach: clinicopathological and immunohistochemical evaluation

Neuroendocrine carcinoma (NEC) of the stomach is an uncommon disease. Because of its rarity, the clinicopathological features are unclear, and there is no consensus on the optimal treatment strategy. This study included five consecutive patients with gastric NEC who underwent surgery from July 2001 to August 2011. Clinical presentation, tumor location, tumor morphology and size, pathology and immunohistochemistry results, and treatment outcome were analyzed retrospectively and discussed. The study cohort of four men and one woman ranged in age from 52 to 84 years, with a median age of 72 years. Positive rates of neuroendocrine markers were 40 % for chromogranin A, 60 % for synaptophysin, 60 % for CD56, 40 % for neuron-specific enolase, and 100 % for p53 protein. Median number of lymph node metastases per patient was 10, with severe lymphatic and venous infiltration, and high Ki-67 labeling index (60-90 %) reported for all patients. Median tumor size was 6 cm. Stage IV disease was diagnosed in three patients; the other two patients showed stage IIIA tumors. After a mean follow-up of 29.8 months, two of the five patients had died of the disease. Although rare, gastric NECs deserve particular attention because of their strong malignant potential associated with an extremely poor prognosis. Such carcinomas demand an aggressive surgical approach followed by chemotherapy and multimodality adjuvant therapy.

Paraneoplastic neurological syndromes associated with gastric cancer: a case report and review of the literature

Paraneoplastic neurological syndromes (PNS) are associated with small-cell lung cancer, breast and gynecological cancers. We describe a gastric neoplasm presented with neurological symptoms. A 74-year-old male presented with tonic-clonic seizures. Initial investigations were normal; however, brain magnetic resonance imaging showed abnormal signal intensity in the hippocampi. A diagnosis of PNS was suspected. The patient was then diagnosed with a gastric neuroendocrine carcinoma with N-type voltage-gated calcium channel antibodies. The neurological impairments improved after the primary was resected and the patient remains free of cancer and paraneoplastic syndrome. We reviewed 10 cases of PNS associated with gastric cancer and found several characteristics: (1) older men, (2) neuroendocrine component or predominance, (3) oncological outcome for patients with PNS is better than for patients without PNS, and (4) neurological impairment is diagnosed 6 months prior to the diagnosis of gastric malignancy. In conclusion, elderly men with symptoms suggestive of PNS should be investigated for a gastric neuroendocrine malignancy.

Primary small cell carcinoma of the stomach: an experience of two decades (1990-2011) in a Chinese cancer institute

BACKGROUND

Primary gastric small cell carcinoma (GSCC) is a rare and aggressive disease for which the standard treatment has not been established. The objective of this study is to investigate the clinical characteristics and survival.

METHODS

All cases of GSCC treated at our institute from January 1990 to December 2011 were reviewed and analyzed retrospectively. Statistical analyses were performed using Fisher's exact test.

RESULTS

A total of 19 patients from 11,603 cases (0.16%) of all gastric cancers treated during this period were identified. The median age was 61 years and the patients were predominantly men. Using the latest AJCC Staging Criteria, the majority of the patients (68.4%) were Stage III. All patients underwent surgery. The median overall survival time (MST) was 19.5 months (95% CI 17.5-21.6 months). The 1-, 3-, and 5-year overall survival rates were 77.3%, 44.2%, and 22.1%, respectively. The MST of 48.5 months for cases who received postoperative adjuvant chemotherapy was superior to that of 19.0 months for cases who did not (P = 0.026).

CONCLUSIONS

Our data indicate that GSCC patients can be treated effectively with combined modality of treatment, despite the aggressive nature of GSCC. Systemic therapy, based on chemotherapy with surgery, is recommended.

A clinicopathological aspect of primary small-cell carcinoma of the uterine cervix: a single-centre study of 25 cases

AIMS

Small-cell carcinoma is a variant of poorly differentiated neuroendocrine carcinoma. Primary small-cell carcinoma of the cervix (SCCC) is recognised as a rare and aggressive malignant tumour with poor prognosis. In this study, the authors report 25 Chinese cases of SCCC, with a particular focus on their clinical and pathological characteristics.

MATERIAL AND METHODS

The records of 25 patients from 4075 Chinese patients with cervical cancer were collected and reviewed, including the patients' age, initial symptoms, cervical tumour size, International Federation of Gynaecology and Obstetrics clinical stage, lymph-node metastasis, treatments and follow-up results. Immunohistochemical detection was performed for cytokeratin, epithelial membrane antigen, neuron-specific enolase (NSE), synaptophysin (Syn), chromogranin A (CgA), neuronal cell adhesion molecules (CD56), thyroid transcriptional factor-1 and S100 protein (S100).

RESULTS

The median age of 25 patients with SCCC was 43.7 years. The most common symptom was abnormal vaginal bleeding. Histologically, there were 19 'homogenous' SCCC samples and six samples of SCCC mixed with adenocarcinoma. The proportion of SCCC samples with positive immunoreactivity were 100.0% for NSE, 96.0% for Syn, 68.0% for CD56, 76.0% for CgA, 40.0% for thyroid transcriptional factor-1, 84.0% for epithelial membrane antigen, 68.0% for cytokeratin and 8.0% for S100, respectively. Every patient received one to three types of treatments, including surgery, chemotherapy and radiotherapy. The median survival time of patients was 20.9 months after diagnosis.

CONCLUSION

The higher proportion of positive labelling of Syn, CD56, CgA, and NSE in SCCC implicated that they are valuably applied in a differential diagnosis of the malignancy. The patients with SCCC receive one to three types of therapies, including surgery, chemotherapy and radiotherapy, and have a poor prognosis.

Unusual case of small cell gastric carcinoma: case report and literature review

BACKGROUND

Small cell carcinomas are among the most aggressive, poorly differentiated, and highly malignant of the neuroendocrine tumors (NETs). Of which, small cell gastric carcinoma is a rare small cell neuroendocrine tumor. The purpose of our study was to present this case and perform a comprehensive literature review.

METHODS AND RESULTS

We review a case of small cell gastric carcinoma that is particularly unusual in that it occurred in a woman from the US when the majority of cases of small cell gastric carcinoma have been reported in men from East Asia, and more specifically, from Japan. The diagnosis was made after endoscopy revealed a large ulcerated mass in the gastric cardia of Borrmann type 3. Biopsies revealed multiple small basophilic cells underlying the squamous epithelium of the esophagus and cardiac mucosa, indicating the presence of a tumor at the gastroesophageal junction. Immunostaining established the diagnosis with positive stains for chromogranin, synaptophysin, and CD56. Our patient is being treated with chemotherapy, but many different treatment regimens have been tried for small cell gastric carcinoma with variable success.

CONCLUSIONS

Overall prognosis for small cell gastric carcinoma is dismal. Neuroendocrine tumors in general have variable clinical behaviors and prognosis is dependent on the neuroendocrine tumor type. The adoption of a standardized classification system for neuroendocrine tumors could improve the recognition of infrequently encountered neuroendocrine tumors like small cell gastric carcinoma and will enhance strategies for treatment and thus improve prognosis for patients with these rare and aggressive tumors.

Extrapulmonary Small Cell Carcinoma of the Stomach: A Lethal Entity

Extrapulmonary small cell carcinoma of the stomach is a rare and aggressive malignancy with a poor prognosis that was first described in 1976 by Matsusaka et al. In 1989 it was recognized by the World Health Organization as an independent entity affecting the stomach. Pure and composite are the two types of gastric small cell carcinoma reported in the literature. We report a case of a 68-year-old African American male with metastatic pure-type extrapulmonary small cell cancer of the stomach. The primary lesion measured approximately 7 cm in diameter on endoscopy. The diagnosis was made on the basis of characteristic histological features of small, round, oval lymphocyte-like cells with hyperchromatic nuclei, and scant cytoplasm consistent with small cell carcinoma. Gastric small cell carcinoma is typically diagnosed at an advanced stage as demonstrated in our case. We conducted a literature review discussing the two types of extrapulmonary small cell carcinoma of the stomach and their prevalence.

Micropapillary carcinoma of stomach: a clinicopathologic and immunohistochemical study of 11 cases

Micropapillary carcinoma (MPC) of the stomach is a rare, newly recognized entity, and only 2 patients with this histology have been reported. We investigated clinicopathologic features, expression of mucin (MUC2, MUC5AC, MUC6, CD10) and cytokeratin profiles (CK7 and CK20), epidermal growth factor receptors (EGFR and HER2), prognostic markers (p53 and Ki-67), and outcomes in 11 MPCs of the stomach. The proportion of MPC component ranged from 5% to 70%. Micropapillary features were often found at the deep advancing edge of the tumor. Endolymphatic tumor emboli were found in 10 cases (91%) and lymph node metastases were found in 4 cases (36%). In MPCs, positive expression was observed for Ki-67 (82%), CK7 (73%), EGFR (64%), p53 (64%), MUC5AC (45%), MUC6 (36%), and CK20 (27%). However, MUC2, CD10, and HER2 expression was negative in all cases. In 9 conventional adenocarcinomas and 11 papillary adenocarcinomas with multiple endolymphatic tumor emboli, used as control, positive expression was observed for Ki-67 (100%), CK7 (90%), EGFR (80%), CK20 (70%), p53 (70%), MUC5AC (70%), MUC6 (60%), MUC2 (40%), CD10 (25%), and HER2 (15%). Expression of MUC2, CK20, and the Ki-67 labeling index was significantly higher in control adenocarcinomas as compared with MPCs (P<0.05). However, there was no significant difference in other clinicopathologic features and overall patient survival. Subclassification of MPCs into 2 subgroups according to the proportion of micropapillary component (cut-off value was 20%) failed to find any significant clinicopathologic differences (P>0.05). Although MPCs in other organs show a poor prognosis, this does not seem to be true for gastric MPCs. Further larger studies are necessary to confirm our initial findings.

An autopsy case of primary small cell gastric carcinoma and adenocarcinoma

A 62-year-old man was emergently admitted to our hospital because of disturbance of consciousness. Computed tomography of the chest and abdomen showed pleural effusion, ascites, and generalized lymphadenopathy. Upper gastrointestinal endoscopy revealed bleeding from an irregular ulcerative lesion in the lesser curvature of the middle portion of the gastric body, and exhibited the morphology of Borrman type 4 gastric cancer. The patient died on the seventh hospital day. At autopsy, a diagnosis of primary small cell gastric carcinoma associated with adenocarcinoma was made. Primary small cell gastric carcinoma and its coexistence with adenocarcinoma, as in this case, is rare.

Primary small cell carcinoma of the stomach successfully treated with cisplatin and etoposide

We report a 44-year-old man with primary gastric small cell carcinoma who showed a remarkable response to chemotherapy specific for pulmonary small cell carcinoma. The patient had been admitted to another local hospital because of intermittent epigastralgia. An upper gastrointestinal examination there revealed an ulcerative tumor, 5 cm in diameter, on the lesser curvature side of the cardia, and endoscopic biopsy reported adenocarcinoma. Computed tomography revealed a mass over the lesser curvature of the stomach and some enlarged regional lymph nodes. Radical total gastrectomy, lymph node dissection, Roux-en-Y esophagojejunostomy and splenectomy were performed at our hospital. Pathology revealed gastric mucosa infiltrated by small-sized tumor cells with scanty cytoplasm and hyperchromatic nuclei. Immunohistochemically, the tumor cells were positive for synaptophysin, chromogranin A, and CD56. Primary gastric small cell carcinoma was diagnosed. The postoperative course, complicated by shock due to bleeding, wound infection and intra-abdominal abscess, took more than 2 months to resolve. Follow-up computed tomography showed tumor recurrence with multiple enlarged lymph nodes in the aortocaval region and hepatic hilum. The patient received palliative chemotherapy consisting of cisplatin 80 mg/m(2) on day 1 and etoposide 80 mg/m(2) on days 1-3 every 28 days, and had partial response to the chemotherapy, with a progression-free survival of 10 months. Chemotherapy with cisplatin and etoposide used for small cell carcinoma of the lung is a good treatment for gastric small cell carcinoma.

Gastric small cell carcinoma successfully treated by surgery and postoperative chemotherapy consisting of cisplatin and S-1: report of a case

We herein report a case of gastric small cell carcinoma (GSCC), which was successfully treated by surgery and postoperative chemotherapy consisting of cisplatin (CDDP) and the fluoropyrimidine S-1. The patient was a 63-year-old man in whom a gastric tumor had been endoscopically detected. The type 1 tumor was located in the gastric body. An abdominal computed tomogram showed many metastasized nodes around the stomach. A total gastrectomy with regional node dissection was performed. The removed tumor was histologically and histochemically diagnosed to be a GSCC with node metastases. Furthermore, washing peritoneal cytology histologically revealed the presence of carcinoma cells. Metastasis was histologically observed in 17 of 24 dissected nodes. After surgery, CDDP was intravenously administered and S-1 was orally administered for 1 year. Consequently, the patient is now well without any recurrence 45 months after surgery. We reviewed 52 Japanese patients with GSCC/endocrine cell carcinoma (EC) reported between 2001 and 2005 with reference to chemotherapy. Chemotherapy using S-1 was performed for 11 of the 52 patients. Four of the 11 patients, including the present case, who were treated with S-1 survived for over 2 years after surgery, although the GSCC/EC of the four patients were staged as III or IV. Therefore, chemotherapy consisting of CDDP and S-1 may provide a survival benefit for patients with GSCC/EC.

A case of primary gastric small cell carcinoma with a rare pattern of lymph node metastasis

We report a very rare case of primary gastric small cell carcinoma (GSCC) that was accompanied with gastric tubular adenocarcinoma. A male in his 60s had an elevated tumor with a central ulceration in the middle stomach. The patient underwent a distal gastrectomy with lymph node dissection. The pathological examination showed two separated lesions of the stomach, which contained the components of primary GSCC and primary gastric tubular adenocarcinoma. Immunohistochemical (IHC) examination demonstrated that the tumor cells in the small cell carcinoma stained positive for synaptophysin, chromogranin A, and neural cell adhesion molecule (NCAM). GSCC cells and adenocarcinoma cells independently metastasized to each regional lymph node. Further studies on the biological behavior of individual tumors may allow the development of new treatment strategies for GSCC.

The pathology of extrapulmonary small cell carcinoma

Extrapulmonary small cell carcinomas (EPSCCs) are uncommon malignant neoplasms with a reported incidence of 0.1% to 0.4% in the United States. Since their first description in 1930, they have been seen in nearly every organ system. Like their more common pulmonary counterparts, EPSCCs are thought to arise from a multipotential stem cell. However, there is recent molecular evidence that small cell elements may arise as a late-stage phenomenon in the genetic progression of more organ-typical carcinomas. The morphologic, immunohistochemical, and ultrastructural features are similar to those described in pulmonary small cell carcinomas (PSCCs). The differential diagnosis of EPSCC includes PSCC, other neuroendocrine tumors, small round blue cell tumors, metastatic melanoma, lymphoma, and poorly differentiated non-small cell carcinomas. Molecular alterations reported to occur in EPSCCs include abnormalities described in PSCC and changes found in carcinomas more typically encountered in the organ from which they arise. In this article we discuss the pathology of EPSCC with a review of theories of histogenesis, sites of occurrence, diagnostic features, differential diagnosis, molecular alterations, and clinical behavior.

Primary small cell carcinoma of the esophagus: clinicopathological and immunohistochemical features of 21 cases

Background

Primary small cell carcinoma (SCC) of the esophagus is a rare and aggressive tumor with poor prognosis. In this study, we report the clinicopathological characteristics of 21 cases of small cell carcinoma of the esophagus treated at the Cancer Center of Sun Yat-Sen University, with particular focus on the histologic and immunohistochemical findings.

Methods

Twenty-one patient records were reviewed including presenting symptoms, demographics, disease stage, treatment, and follow-up. Histologic features were observed and immunohistochemical detection of cytokeratin (CK), epithelial membrane antigen (EMA), neuron specific enolase (NSE), synaptophysin (Syn), chromogranin A (CgA), neuronal cell adhesion molecules (CD56), thyroid transcriptional factor-1 (TTF-1) and S100 protein (S100) was performed.

Results

The median age of patients in the study was 56 years, with a male-to-female ratio of 3.2:1. Histologically, there were 19 "homogenous" SCC esophageal samples and 2 samples comprised of SCC and well-differentiated squamous cell carcinoma. The percentages of SCC samples with positive immunoreactivity were Syn 95.2%, CD56 76.2%, TTF-1 71.4%, NSE 61.9%, CgA 61.9%, CK 57.1%, EMA 61.9%, and S100 19.0%, respectively. The median patient survival time was 18.3 months after diagnosis. The 2-year survival rate was 28.6%.

Conclusion

Our study suggests that esophageal SCC has similar histology to SCC that arises in the lung compartment, and Chinese patients have a poor prognosis. Higher proportion of positive labeling of Syn, CD56, CgA, NSE, and TTF-1 in esophageal SCC implicate that they are valuably applied in differential diagnosis of the malignancy.

Mixed small cell carcinomas of the uterine cervix: prognostic impact of focal neuroendocrine differentiation but not of Ki-67 labeling index

Small cell neuroendocrine carcinomas sometimes represent a non-small cell component. Because of infection with the high-risk human papillomavirus of small cell carcinomas (SmCCs), several host cell regulatory proteins are altered, thus causing altered proliferative activity. Knowledge regarding the prognostic impact of focal neuroendocrine differentiation in mixed SmCCs and the value of proliferative activity in these tumors is very limited. Small cell carcinomas were selected for immunohistochemical staining with neuroendocrine markers and Ki-67. In cases with mixed tumors, the percentage of the SmCC component was calculated and correlated with survival. Of 677 tumors, 9 (1.3%) were classified as SmCCs after Grimelius staining (8/9 positive tumors) and immunohistochemical reaction against neuron-specific enolase, chromogranin A, synaptophysin (7/9 positive tumors), and CD56 (8/9 positive tumors); all specimens were positive for at least 2 of these. CD99 staining was completely negative. Two thirds of the SmCCs showed non-small cell differentiation. Four patients died of the tumor after a median time of 36.7 months (range, 15-56 months). Even an SmCC component of 17% was associated with a fatal course. Small cell carcinoma represented a significantly lower proliferation (Ki-67 labeling index) than did the non-small cell component in the same tumor (12.8% vs 70.8%; P < .001). Even a small SmCC component in mixed carcinomas of the uterine cervix was associated with adverse outcome. Proliferative activity, determined by Ki-67 labeling index, is of no prognostic value.

Primary gastric small cell carcinoma: report of a case and review of the literature

A 52-year-old man suffering from a pure-type primary gastric small cell carcinoma was treated with surgery and combination chemotherapy. The small cell carcinoma, approximately 6.5 cm in diameter, was situated in the posterior wall of the antrum and there were no distant metastases. Total gastrectomy and regional lymph node dissection was carried out. Histological examination revealed a solid pattern of proliferation of small cells with hyperchromatic, round nuclei and scant cytoplasm. Neoplastic cells infiltrated into the subserosal layer with severe lymphatic and vascular invasion. Regional lymph node cells were mostly replaced by tumor cells that stained positive for Grimelius, neuron-specific enolase (NSE), and synaptophysin. Accumulations of electron-dense core granules in the small neoplastic cells were seen by electron microscopy. Following surgery, the patient was treated with adjuvant chemotherapy consisting of cisplatin and etoposide. The patient is alive and recurrence free 3 years after surgical operation. We review 107 published cases of primary gastric small cell carcinoma, an extremely rare disease first reported in 1976. Small cell carcinoma is an aggressive, malignant tumor. Intensive chemotherapy is essential for patient survival even when curative surgical resection is carried out.

Gastric small cell carcinoma with marked response to neoadjuvant chemotherapy

We report a patient with gastric small cell carcinoma (SCC) who showed a marked response to neoadjuvant chemotherapy. The patient was a 72-year-old Japanese man who was admitted because of epigastralgia. Subsequent examination revealed the presence of advanced gastric carcinoma in the lesser curvature of the lower body of the stomach, with multiple abdominal lymph node metastases. Endoscopic biopsy specimens from the tumor revealed SCC with moderately differentiated adenocarcinoma. The patient received neoadjuvant chemotherapy consisting of carboplatin (400 mg/m2, for 1 day), epirubicin (27 mg/m2, for 1 day), etoposide (70 mg/m2, for 3 days), and 5-fluorouracil (330 mg/m2, for 11 days). Clinically, the primary tumor and lymph node metastases were markedly reduced. Subsequently the patient underwent curative surgery and was alive without recurrence for more than 3 years after the surgery.

Combined small-cell carcinoma of the stomach: p53 and K-ras gene mutational analysis supports a monoclonal origin of three histological components

Primary small-cell carcinoma (SmCC) is extremely rare in stomach. We reported an autopsy case of combined gastric SmCC with p53 and K-ras mutational analysis. Histologically, the tumour was composed of well-differentiated adenocarcinoma surrounding the central dominant SmCC component with scattered nests of squamous cell carcinoma. Immunohistochemically, all the neoplastic components revealed strong expression for p53 protein. Based on these findings, we hypothesized that these histologically different components originated from a same progenitor cell that possessed p53 mutation. Using Laser-capture microdissection technique and mutational analysis, we identified the same point mutations of p53 gene (A-->G transversion in codon 239) and K-ras gene (G-->A transversion in codon 13) in all the neoplastic components, but not in the adjacent normal gastric epithelium. Our results strongly support a hypothesis that the combined SmCC of stomach in this case was of monoclonal origin.