Genetic evolution of alpha fetoprotein producing gastric cancer

An Interesting Case of Alpha-Fetoprotein (AFP)-Producing Pancreaticoduodenal Tumor

Alpha-fetoprotein (AFP) is considered one of the best-known predictive serum markers, playing a crucial role in cancer investigation and subsequent treatment. In most adult cells, the production of this marker is suppressed after embryogenesis. However, its increased level raises concerns about underlying malignant conditions, which provide a valuable diagnostic tool for medical professionals in oncology. The existing AFP-producing adenocarcinomas exhibit unique clinical characteristics, including high malignancy and early metastatic potential, which result in poorer outcomes. To illustrate these characteristics, we decided to describe a case report of a 70-year-old African American female with a significantly elevated level of AFP. Further pathology results confirmed a duodenal adenocarcinoma versus adenocarcinoma from the pancreas. While AFP-producing adenocarcinoma has multiple underlying molecular mechanisms that correlate with poor prognosis, definitive treatment based on molecular pathways has yet to be defined. Therefore, further research is needed for new therapeutic modalities.

Pulmonary invasive mucinous adenocarcinoma

Invasive mucinous adenocarcinoma (IMA) is a relatively rare subtype of lung adenocarcinoma, composed of goblet and/or columnar tumour cells containing abundant intracytoplasmic mucin vacuoles. While a majority of IMAs are driven by KRAS mutations, recent studies have identified distinct genomic alterations, such as NRG1 and ERBB2 fusions. IMAs also more frequently present as a pneumonic-like pattern with multifocal and multilobar involvement, and comparative genomic profiling predominantly shows a clonal relationship, suggesting intrapulmonary metastases rather than synchronous primary tumours. Accordingly, these unique features require different therapeutic approaches when compared to nonmucinous adenocarcinomas in general. In this article, we review recent updates on the histopathological, clinical, and molecular features of IMAs, and also highlight some unresolved issues for future studies.

Hepatoid adenocarcinoma-Clinicopathological features and molecular characteristics

Hepatoid adenocarcinoma (HAC) is a rare, malignant, extrahepatic tumor with histologic features similar to those of hepatocellular carcinoma. HAC is most often associated with elevated alpha-fetoprotein (AFP). HAC can occur in multiple organs, including the stomach, esophagus, colon, pancreas, lungs, and ovaries. HAC differs greatly from typical adenocarcinoma in terms of its biological aggression, poor prognosis, and clinicopathological characteristics. However, the mechanisms underlying its development and invasive metastasis remain unclear. The purpose of this review was to summarize the clinicopathological features, molecular traits, and molecular mechanisms driving the malignant phenotype of HAC, in order to support the clinical diagnosis and treatment of HAC.

Comprehensive Analysis of Genomic Alterations in Hepatoid Adenocarcinoma of the Stomach and Identification of Clinically Actionable Alterations

Simple Summary

Hepatoid adenocarcinoma of the stomach (HAS) is a subset of gastric cancer (GC) histologically characterized by hepatocellular carcinoma-like foci with or without alpha-fetoprotein secretion, which is easily misdiagnosed. Genomic alterations and potential targets for this population are still largely unknown. Additionally, treatment regimens of HAS are mainly based on GC guidelines, which is not reasonable for diseases with great heterogeneity. The present study comprehensively depicts the genomic features of HAS, and they are significantly different from GC, AFP-producing GC (AFPGC), and liver hepatocellular carcinoma (LIHC). Multiple aggressive behavior-related amplificated or deleted regions in HAS are firstly reported. Moreover, reliable and practicable clinically actionable alterations for HAS are identified, providing evidence for making personalized therapy based on the genomic characteristics of HAS instead of GC.

Abstract

Hepatoid adenocarcinoma of the stomach (HAS) is a rare malignancy with aggressive biological behavior. This study aimed to compare the genetic landscape of HAS with liver hepatocellular carcinoma (LIHC), gastric cancer (GC), and AFP-producing GC (AFPGC) and identify clinically actionable alterations. Thirty-eight cases of HAS were collected for whole-exome sequencing. Significantly mutated genes were identified. TP53 was the most frequently mutated gene (66%). Hypoxia, TNF-α/NFκB, mitotic spindle assembly, DNA repair, and p53 signaling pathways mutated frequently. Mutagenesis mechanisms in HAS were associated with spontaneous or enzymatic deamination of 5-methylcytosine to thymine and defective homologous recombination-related DNA damage repair. However, LIHC was characteristic of exposure to aflatoxin and aristolochic acid. The copy number variants (CNVs) in HAS was significantly different compared to LIHC, GC, and AFPGC. Aggressive behavior-related CNVs were identified, including local vascular invasion, advanced stages, and adverse prognosis. In 55.26% of HAS patients there existed at least one clinically actionable alteration, including ERBB2, FGFR1, CDK4, EGFR, MET, and MDM2 amplifications and BRCA1/2 mutations. MDM2 amplification with functional TP53 was detected in 5% of HAS patients, which was proved sensitive to MDM2 inhibitors. A total of 10.53% of HAS patients harbored TMB > 10 muts/Mb. These findings improve our understanding of the genomic features of HAS and provide potential therapeutic targets.

The Value of Perioperative Chemotherapy for Patients With Hepatoid Adenocarcinoma of the Stomach Undergoing Radical Gastrectomy

BACKGROUND

Hepatoid adenocarcinoma of the stomach (HAS) is a rare type of gastric cancer, but the role of perioperative chemotherapy is still poorly understood. The aim of this retrospective study was to investigate the associations between perioperative chemotherapy and prognosis of HAS.

METHOD

We retrospectively analyzed patients with locally advanced HAS who received radical surgery in Peking University Cancer Hospital between November 2009 and October 2020. Patients were divided into neoadjuvant chemotherapy-first (NAC-first) group and surgery-first group. The relationships between perioperative chemotherapy and prognosis of HAS were analyzed using univariate, multivariate survival analyses and propensity score matching analysis (PSM).

RESULTS

A total of 100 patients were included for analysis, including 29 in the NAC-first group and 71 in the surgery-first group. The Her-2 amplification in HAS patients was 22.89% (19/83). For NAC-first group, 4 patients were diagnosed as tumor recession grade 1 (TRG1), 4 patients as TRG 2, and 19 patients as TRG 3. No significant difference in prognosis between the surgery-first group and the NAC-first group (P=0.108) was found using PSM analysis. In the surgery-first group, we found that the survival rate was better in group of ≥6 cycles of adjuvant chemotherapy than that of <6 cycles (P=0.013).

CONCLUSION

NAC based on platinum and fluorouracil may not improve the Overall survival (OS) and Disease-free survival time (DFS) of patients with locally advanced HAS. Patients who received ≥6 cycles of adjuvant chemotherapy had better survival. Therefore, the combination treatment of radical gastrectomy and sufficient adjuvant chemotherapy is recommended for patients with locally advanced HAS.

Hepatoid esophagogastric adenocarcinoma and tumoral heterogeneity: a case report

Hepatoid adenocarcinoma of the stomach is an uncommon subtype of gastric cancer remarkably similar to hepatocellular carcinoma in histopathological analysis. It is also commonly associated with high serum alfa-fetoprotein and a poorer prognosis, despite the emergence of new therapeutic options. In recent years, next generation sequencing (NGS) technology has made it possible to identify and describe the genes and molecular alterations common to gastric cancer thereby contributing to the advancement of targeted therapies. A 62-year-old patient, with no prior risk factor for hepatocellular carcinoma (HCC), presented to the emergency room with dysphagia for solids, abdominal pain and weight loss of about 3 kilograms over 3 months. Histopathological analysis presented with disparities regarding HER2 and programmed death-ligand 1 (PD-L1) status in the primary and metastatic sites. We describe a case of a de novo metastatic, human epidermal growth factor receptor 2 (HER2) positive esophagogastric junction hepatoid adenocarcinoma. Although this is a rare subgroup of gastric cancer, treatment strategies were based in recent studies in immunotherapy and guided therapy, taking into consideration the molecular findings from the patient's tumor NGS analysis. Data about HER2 and PDL1 heterogeneity were also reviewed. Despite the aggressiveness and rarity of this histology, the patient had a good response to treatment.

Hepatoid Adenocarcinoma of the Stomach: Current Perspectives and New Developments

Hepatoid adenocarcinoma of the stomach (HAS) is a rare malignant tumor, accounting for only 0.17-15% of gastric cancers. Patients are often diagnosed at an advanced disease stage, and their symptoms are similar to conventional gastric cancer (CGC) without specific clinical manifestation. Morphologically, HAC has identical morphology and immunophenotype compared to hepatocellular carcinoma (HCC). This is considered to be an underestimation in diagnosis due to its rare incidence, and no consensus is reached regarding therapy. HAS generally presents with more aggressive behavior and worse prognosis than CGC. The present review summarizes the current literature and relevant knowledge to elaborate on the epidemic, potential mechanisms, clinical manifestations, diagnosis, management, and prognosis to help clinicians accurately diagnose and treat this malignant tumor.

Effect of Immune Checkpoint Inhibitors Plus Chemotherapy on Advanced Gastric Cancer Patients with Elevated Serum AFP or Hepatoid Adenocarcinoma

Purpose

Alpha-fetoprotein-producing gastric cancer (AFPGC) and hepatoid adenocarcinoma of stomach (HAS) are rare types of gastric cancer, with specific clinical manifestations and poor prognosis. The standardized treatment process of such cancers remains elusive. We aim to investigate the efficacy of immunotherapy combined with chemotherapy on patients with AFPGC or HAS.

Patients and Methods

AFPGC and HAS patients who underwent immunotherapy and/or chemotherapy as the first-line treatment at our institute from June 2016 to December 2018 were enrolled in this observational study. Their clinicopathological characteristics, serum AFP level and treatment methods were collected. The progression-free survival (PFS) and overall survival (OS) were analyzed and compared between patients who received immunotherapy plus chemotherapy and those received chemotherapy.

Results

A total of 21 patients with advanced AFPGC or HAS were included in the study and the median follow-up time was 28.0 months. Of the 21 patients, 7 patients received immunotherapy of PD-1 antibody (nivolumab) plus chemotherapy and 14 patients as control received chemotherapy with or without Herceptin/Apatinib. The median progression-free survival (mPFS) time was 5.0 months (4.3 months in the control group and 22.0 months in the immunotherapy group). The median overall survival (mOS) time of the control group was 16.0 months (14.0 months in chemotherapy alone subgroup, 20.0 months in chemotherapy plus Apatinib or Herceptin subgroup), while the mOS of patients receiving immunotherapy was not reached.

Conclusion

This study suggested PD-1 checkpoint inhibitor plus chemotherapy could benefit AFPGC and HAS patients. Its mechanism of action warrants further investigation.

The prognosis of hepatoid adenocarcinoma of the stomach: a propensity score-based analysis

BACKGROUND

To investigate whether there is a distinct difference in prognosis between hepatoid adenocarcinoma of the stomach (HAS) and non-hepatoid adenocarcinoma of the stomach (non-HAS) and whether HAS can benefit from radical surgery.

METHODS

We retrospectively reviewed 722 patients with non-HAS and 75 patients with HAS who underwent radical gastrectomy between 3 November 2009 and 17 December 2018. Propensity score matching (PSM) analysis was used to eliminate the bias among the patients in our study. The relationships between gastric cancer type and overall survival (OS) were evaluated by the Kaplan-Meier method and Cox regression.

RESULTS

Our data demonstrate that there was no statistically significant difference in the OS between HAS and non-HAS {K-M, P = log rank (Mantel-Cox), (before PSM P = 0.397); (1:1 PSM P = 0.345); (1:2 PSM P = 0.195)}. Moreover, there were no significant differences in the 1-, 2-, or 3-year survival rates between patients with non-HAS and patients with HAS (before propensity matching, after 1:1 propensity matching, and after 1:2 propensity matching).

CONCLUSION

HAS was generally considered to be an aggressive gastric neoplasm, but its prognosis may not be as unsatisfactory as previously believed.

Clinicopathological features and prognosis of AFP-producing colorectal cancer: a single-center analysis of 20 cases

Background: High serum levels of alpha-fetoprotein (AFP) are observed in some gastrointestinal cancers. However, primary AFP-producing colorectal cancer (CRC) is extremely rare and causes confusion among clinicians. In this study, we analyzed the clinicopathological features and clinical outcomes of AFP-producing CRC and provide a brief view of this rare carcinoma.

Patients and methods: Twenty patients with AFP-producing CRC were enrolled at the Fudan University Shanghai Cancer Center from 2012 to 2015. Clinical information, including serum AFP and CEA levels, and outcomes were collected. Tumors were divided into three histologic types: the common adenocarcinoma (COM) type, mucinous adenocarcinoma type and hepatoid type (HPT). Immunohistochemical (IHC) staining of GPC3, Hepa-1, SALL4 and Arg-1 was performed. Additionally, mutations of the KRAS, NRAS and BRAF genes were examined. Finally, another 40 stage-matched patients with traditional CRC were enrolled as controls for survival analysis.

Results: AFP-producing CRC was more likely to occur in males (60%) and arose mainly from the ascending (40%) and sigmoid (35%) colon. In addition, the majority of patients with AFP-producing CRC had poor differentiation (50%), advanced local invasion (80%) and lymph node (LN) metastasis (60%). Synchronous distant metastasis was commonly observed (35%). Interestingly, serum AFP levels were closely associated with LN metastasis. Histopathologically, the COM type was the most common pattern. In IHC staining, the HPT pattern was the most distinct due to high positivity rates of GPC3, Hepa-1 and Arg-1. One patient had mismatch repair deficiency, and another had a KRAS mutation. Patients with AFP-producing CRC had worse progression-free and overall survival than patients with traditional CRC.

Conclusion: AFP-producing CRC has unique clinical and histopathological characteristics, showing an aggressive biological behavior and worse prognosis than traditional CRC.

Frequent loss of heterozygosity of SMAD4 locus and prognostic impacts of SMAD4 immunohistochemistry in gastric adenocarcinoma with enteroblastic differentiation

Gastric adenocarcinoma with enteroblastic differentiation (GAED) is a rare variant of gastric adenocarcinoma. Clinicopathologically, GAED is known to be aggressive and is characterized by frequent vascular invasion, lymphatic invasion, and liver metastasis even in early stages. SMAD4 was identified as a frequently deleted gene in GAED by copy number variation analysis in our previous next-generation sequencing study; therefore, we examined the clinicopathological impacts of SMAD4 in 51 cases of GAEDs (early: 17, advanced: 34). We performed Sanger sequencing for SMAD4 mutations and loss of heterozygosity (LOH) analysis of the SMAD4 locus, in addition to immunohistochemistry for SMAD4, to determine its clinicopathological correlations and impacts on survival. The frequency of LOH at the SMAD4 locus was 45.1%, and it was significantly higher in GAED compared to in conventional gastric adenocarcinoma. SMAD4 mutations were not found in any case. Reduced SMAD4 expression was found in 60.8% of cases; it was significantly correlated with advanced stages and lymph node metastasis and showed trends of larger tumor size and lymphatic invasion. Reduced SMAD4 expression in metastatic lymph nodes was found in 21 of 36 cases. Survival analysis revealed that reduced SMAD4 expression significantly affected the patient's overall survival (OS) and recurrence-free survival (RFS), although multivariate analysis showed that only liver metastasis and lymphatic infiltration (Ly+) were independent prognostic factors for OS and RFS. The SMAD4 locus is one of the susceptibility genes in this tumor, although SMAD4 mutation was not detected. Furthermore, the inactivation of SMAD4 appeared to contribute to the aggressiveness of GAED.

Hepatoid adenocarcinoma of the stomach: a unique subgroup with distinct clinicopathological and molecular features

OBJECTIVES

Hepatoid adenocarcinoma of the stomach (HAS) is characterized by histological resemblance to hepatocellular carcinoma and a poor prognosis. The aim of this study is to elucidate the clinicopathological and molecular characteristics of HAS.

METHODS

Forty-two patients with HAS who received gastrectomy were enrolled in this study. Based on a panel of 483 cancer-related genes, targeted sequencing of 24 HAS and 22 clinical parameter-matched common gastric cancer (CGC) samples was performed. Prognostic factors for overall survival (OS) and disease-free survival (DFS) were analysed with the Kaplan-Meier method.

RESULTS

The most frequently mutated gene in both HAS and CGC was TP53, with a mutation rate of 30%. Additionally, CEBPA, RPTOR, WISP3, MARK1, and CD3EAP were identified as genes with high-frequency mutations in HAS (10-20%). Copy number gains (CNGs) at 20q11.21-13.12 occurred frequently in HAS, nearly 50% of HAS tumours harboured at least one gene with a CNG at 20q11.21-13.12. This CNG tended to be related to more adverse biobehaviour, including poorer differentiation, greater vascular and nerve invasion, and greater liver metastasis. Pathway enrichment analysis revealed that the HIF-1 signalling pathway and signalling pathways regulating stem cell pluripotency were specifically enriched in HAS. The survival analysis showed that a preoperative serum AFP level ≥ 500 ng/ml was significantly associated with poorer OS (p = 0.007) and tended to be associated with poorer DFS (p = 0.05).

CONCLUSION

CNGs at 20q11.21-13.12 happened frequently in HAS and tended to be related to more adverse biobehaviour. The preoperative serum AFP level was a sensitive prognostic biomarker for DFS and OS.

Early Gastric Cancer with Purely Enteroblastic Differentiation and No Conventional Adenocarcinoma Component

Gastric carcinoma with enteroblastic differentiation (GCED) is a rare variant of gastric carcinoma, and a part of GCED produces alpha-fetoprotein. GCED is characterized by cells with clear cytoplasm and a tubulopapillary and solid growth pattern resembling those in the primitive gut. GCED is typically overlaid by a conventional adenocarcinoma (CA) component, implying that CA in the mucosa differentiates into GCED during tumor invasion and proliferation. We present the case of a 73-year-old woman with a 10-mm superficial elevated lesion and a slight central depression at the anterior wall of the lower gastric body. Endoscopic submucosal dissection revealed tumor cells having clear cytoplasm and severely atypical nuclei characteristic of GCED. The growth pattern was predominantly solid and trabecular but included submucosal layer invasion and limited tubular growth. Atrophic pyloric mucosa without intestinal metaplasia surrounded the tumor. Immunohistochemically, the tumor cells were positive for AFP, GPC3, and SALL4. The present patient showed a purely enteroblastic differentiation without a CA component despite the presence of early cancer, indicating that few cases of GCED may arise de novo in the gastric mucosa. GCED is more aggressive compared with CA; therefore, pathologists should be aware that GCED without CA can appear in biopsy specimens of early cancer while making an accurate diagnosis.

Efficacy and tolerability of AFPep, a cyclic peptide with anti-breast cancer properties

PURPOSE

The purpose of this study is to assess the efficacy and safety profile of AFPep, a 9-amino acid cyclic peptide prior to its entry into pre-clinical toxicology analyses en route to clinical trials.

METHODS

AFPep was assessed for anti-estrogenic activity in a mouse uterine growth assay and for breast cancer therapeutic efficacy in a human tumor xenograft model in mice. AFPep was assessed for tolerability in a variety of in vivo models, notably including assessment for effects on rat liver and human hepatocellular carcinoma cell lines and xenografts.

RESULTS

AFPep arrests the growth of human MCF-7 breast cancer xenografts, inhibits the estrogen-induced growth of mouse uteri, and does not affect liver growth nor stimulate growth of human hepatocellular carcinoma cell lines when growing in vitro or as xenografts in vivo. AFPep is well tolerated in mice, rats, dogs, and primates.

CONCLUSIONS

AFPep is effective for the treatment of ER-positive breast cancer and exhibits a therapeutic index that is substantially wider than that for drugs currently in clinical use. The data emphasize the importance of pursuing pre-clinical toxicology studies with the intent to enter clinical trials.

HCRP1 downregulation confers poor prognosis and induces chemoresistance through regulation of EGFR-AKT pathway in human gastric cancer

The current study aims to investigate the biological roles and clinical significance of HCRP1 in human gastric cancer. The expression pattern of HCRP1 in gastric cancer tissue and adjacent non-cancerous tissue was detected by immunohistochemistry. HCRP1 downregulation was found in 57 of 137 human gastric cancer samples and correlated with advanced TNM stage, positive nodal status, and relapse. Log-rank test showed that HCRP1 downregulation also correlated with poor overall survival and reduced relapse-free survival. In addition, we found that HCRP1 overexpression inhibited proliferation, colony formation, and invasion in HGC-27 cells. On the other hand, HCRP1 depletion by small interfering RNA promoted proliferation, colony formation, and invasion in SGC-7901 cells. We also treated gastric cancer cells with cisplatin. MTT and Annexin V/PI analysis were carried out to examine change of chemoresistance. We found that HCRP1 overexpression sensitized HGC-27 cells to cisplatin while its depletion reduced sensitivity in SGC-7901 cells. Moreover, we found that HCRP1 overexpression negatively regulated cyclin D1, MMP-2, p-EGFR, p-ERK, and p-AKT. HCRP1 depletion showed the opposite effects. In conclusion, our results suggest that HCRP1 downregulation might serve as an indicator for poor prognosis in gastric cancer patients. HCRP1 reduces drug resistance through regulation of EGFR-AKT signaling.

An Alpha Fetoprotein Producing Gastric Tumor with Yolk Sac, Hepatoid and Papillary Adenocarcinoma Components

Alpha Fetoprotein (AFP) producing gastric carcinomas are very rare and have unique clinicopathological features and an extremely poor prognosis. Here, we report a case of AFP producing gastric carcinoma with three distinct histomorphologic patterns such as yolk sac like, hepatoid, tubular and papillary adenocarcinoma components. The uniqueness of this case is absence of metastases and associated findings such as fundic gland polyposis with varying degrees of dysplasia, gastric and duodenal well differentiated neuroendocrine tumour and rectal ganglioneuroma. The patient is symptom free as of two and half year's postoperative period. AFP producing gastric tumours although rare, need to be identified as it is known to carry poor prognosis.

Hepatoid adenocarcinoma of the stomach--proper identification and treatment remain a challenge

OBJECTIVE

The term hepatoid adenocarcinoma (HAC) of the stomach was introduced three decades ago with the observation of high serum α-fetoprotein (AFP) levels in some gastric adenocarcinoma patients. This very rare gastric cancer patient subgroup is likely frequently misdiagnosed.

MATERIAL

Two patients who were recently diagnosed with HAC of the stomach at our institution are presented. We also performed a structured literature search and reviewed pertinent articles to provide knowledge to improve the proper identification, diagnosis and management of patients with gastric HAC.

RESULTS

HAC is a rare subgroup of gastric carcinoma with poor prognosis. Clinical management of this population may be challenging. The scientific literature is largely based on very small patient series or case reports, and the evidence for proper decision making and management is considered weak.

CONCLUSION

All physicians involved in the diagnosis and treatment of patients with gastric cancer should pay attention to this rare subgroup to improve identification.

Salvage surgery after chemotherapy with S-1 plus cisplatin for α-fetoprotein-producing gastric cancer with a portal vein tumor thrombus: a case report

BACKGROUND

Patient with α-Fetoprotein (AFP)-producing gastric cancer usually has a short survival time due to frequent hepatic and lymph node metastases. Gastric cancer with portal vein tumor thrombus (PVTT) is rare and has an extremely poor prognosis.

CASE PRESENTATION

A 63-year-old man was found to have a huge Type 3 gastric cancer with a PVTT and a highly elevated serum AFP level. Chemotherapy with S-1 plus cisplatin was given to this patient with unresectable gastric cancer for 4 months. The serum AFP level decreased from 6,160 ng/mL to 60.7 ng/mL with chemotherapy. Since the PVTT disappeared after the chemotherapy, the patient underwent total gastrectomy. Histological findings of the primary tumor after chemotherapy showed poorly differentiated adenocarcinoma without hepatoid cells and viable tumor cells remaining in less than 1/3 of the neoplastic area of mucosa and one lymph node. The cancerous cells were immunohistochemically stained by anti-AFP antibody. The patient has survived for 48 month without recurrence.

CONCLUSIONS

AFP-producing gastric cancer with a PVTT has an extremely poor prognosis, but long-term survival was achieved for this dismal condition by salvage surgery after chemotherapy.

[Clinicopathological characteristics and prognosis of alpha-fetoprotein producing gastric cancer]

BACKGROUND/AIMS

Several studies reported a subgroup of gastric cancer patients showing elevated serum alpha-fetoprotein (AFP) at the time of diagnosis. We investigated the clinicopathological characteristics and prognostic factors of AFP producing gastric cancer (AFPPGC) by comparing with AFP non-producing gastric cancer (AFPNPGC).

METHODS

A total of 909 patients were diagnosed with gastric cancer from January 2005 to March 2013 at Gyeongsang National University Hospital and their AFP levels were measured at the time of diagnosis. After excluding 138 patients with underlying liver diseases, 34 patients with elevated serum AFP level over 10 mg/mL were assigned to AFPPGC group and the remaining 737 patients with serum level of AFP below 10 ng/mL were assigned to AFPNPGC group.

RESULTS

The median survival length was shorter in AFPPGC group than AFPNPGC group (18.3 ± 25.5 months vs. 30.0 ± 22.0 months, p=0.004). The incidence of liver metastasis (47.1% vs. 3.3%, p<0.001) and lymph node metastasis (91.2% vs. 31.6%, p<0.001) was significantly higher in AFPPGC group. The probability of encountering metachronous liver metastasis after the operation was higher in AFPPGC group (44.4% vs. 2.0%, p<0.001). Multivariate analysis revealed that patients in the AFPPGC group who received chemotherapy (p=0.037) or underwent operation (p=0.001) had a better survival rate.

CONCLUSIONS

AFPPGC behaves more aggressively and shows a worse prognosis. Therefore, serum AFP level should be routinely checked in all patients diagnosed with gastric cancer.

Gastrointestinal Obstruction due to Solitary Lymph Node Recurrence of Alpha-Fetoprotein-Producing Gastric Carcinoma with Enteroblastic Differentiation

We report an unusual case of alpha-fetoprotein (AFP)-producing gastric carcinoma with enteroblastic differentiation. A 75-year-old woman was admitted to our hospital with occasional upper abdominal discomfort. We performed gastroscopy and observed a type 2 tumor, primarily in the pyloric region. Histological examination of biopsies confirmed gastric adenocarcinoma. Based on these findings, we diagnosed gastric adenocarcinoma and performed laparoscopic distal gastrectomy with lymph node dissection. Histological examination revealed an invasive lesion composed of adenocarcinoma with a tubulopapillary growth pattern. Tumor cells were cuboidal in shape with characteristically clear cytoplasm rich in glycogen. Two regional lymph node metastases were seen microscopically. Immunohistochemically these cells were positive for AFP, carcinoembryonic antigen, caudal-type homeobox transcription factor 2 and common acute lymphoblastic leukemia antigen. The final diagnosis was AFP-producing gastric carcinoma with enteroblastic differentiation. 26 months after initial surgery, the patient was readmitted to our hospital for gastrointestinal obstruction due to lymph node recurrence.

Histologic and immunohistochemical analyses of α-fetoprotein--producing cancer of the stomach

BACKGROUND AND AIM

As the histogenesis and development of α-fetoprotein-producing gastric cancer (AFPGC) have not yet been elucidated, we analyzed the histologic and immunologic relationship between the histologic type of the mucosal lesion considered to be the primary lesion, and that of its invasive lesion, in 36 cases of AFPGC.

PATIENTS AND METHODS

We reviewed 23 AFPGCs with mucosal lesions (1 mucosal and 22 submucosal or deeper invasive tumors) among 36 AFPGCs that had been resected endoscopically or surgically between 1970 and 2005. AFPGC was defined as a tumor showing immunohistochemical positivity for either α-fetoprotein (AFP) or glypican-3. Histologic types were divided into hepatoid (HPT), enteroblastic (ENT), yolk sac tumor, and common (COM) adenocarcinoma type. The tumor phenotypes were classified into gastric, gastrointestinal, and intestinal types on the basis of immunohistochemical analysis.

RESULTS

Among the histologic types of mucosal lesions, the COM and ENT mixed type was observed in 65.2% of cases (15/23 patients), COM alone in 26.1% (6/23), and ENT alone in 8.7% (2/23) of cases. Among the invasive lesions, 16 cases (72.7%) were HPT. Both AFP and glypican-3 were positive in 60.9% (14/23) of mucosal lesions and in 90.9% (20/22) of invasive lesions. With regard to phenotypic expression, 82.6% (19/23) of mucosal lesions were the intestinal type, compared with 95.5% (21/22) of invasive lesions.

CONCLUSIONS

These findings suggest that many cases of AFPGC develop as COM or ENT in the mucosa, which differentiate into ENT and HPT during the process of tumor invasion and proliferation, acquiring AFP production ability.

Primary hepatoid adenocarcinoma of the uterine corpus: A case report with immunohistochemical study for expression of liver-enriched nuclear factors

We report a case of hepatoid adenocarcinoma of the uterus in an 86-year-old woman. Serum AFP was elevated (7824ng/ml) on admission. The surgical specimen obtained by simple hysterectomy and bilateral salpingo-oophorectomy showed an exophytic tumor, 10.5cm×6.0cm×3.7cm in size, in the uterine corpus. Microscopically, tumor cells proliferated in trabecular or cord-like arrangement, which was considered as "hepatoid appearance". An adenocarcinomatous component was intermingled. The expressions of liver-enriched transcription factors, hepatocyte nuclear factor (HNF)-1β, HNF-3, HNF-4α, and CCAAT/enhancer binding protein (C/EBP)-β, were investigated in the present case and in 19 cases of endometrioid adenocarcinoma (11 cases of Grade 2 and 8 cases of Grade 3), because these nuclear factors are involved in embryonal hepatogenesis. HNF-4α was diffusely positive in the present case, but negative in all cases of endometrioid adenocarcinoma. HNF-3 and C/EBP-β were positive for the present case and control adenocarcinoma cases (HNF-3, 36.8% and C/EBP-β, 84.2%). HNF-1β was negative for both the present case and endometrioid adenocarcinomas. This is the first report to demonstrate HNF-4α expression in this rare uterine tumor.

Protein induced by vitamin K absence or antagonist II-producing gastric cancer

Protein induced by vitamin K absence or antagonist II (PIVKA-II) is a putative specific marker of hepatocellular carcinoma (HCC), but it may also be produced by a small number of gastric cancers. To date, 16 cases of PIVKA-II-producing gastric cancer have been reported, 2 of which were reported by us and all of which were identified in Japan. There are no symptoms specific to PIVKA-II-producing gastric cancer, and the representative clinical symptoms are general fatigue, appetite loss, and upper abdominal pain. Serum alpha-fetoprotein (AFP) levels are also increased in almost all cases. Liver metastasis is observed in approximately 80% of cases and portal vein tumor thrombus is observed in approximately 20% of cases. Differential diagnosis between metastatic liver tumor and HCC is often difficult. Grossly, almost all cases appear as advanced gastric cancer. Histologically, a hepatoid pattern is observed in many cases, in addition to a moderately to poorly differentiated adenocarcinoma component. The production of PIVKA-II and AFP is usually confirmed using immunohistochemical staining. Treatment and prognosis largely depends on the existence of liver metastasis, and the prognosis of patients with liver metastasis is very poor. PIVKA-II may be produced during the hepatocellularmetaplasia of the tumor cells.

Strategies for treating liver metastasis from gastric cancer

The prognosis of patients with liver metastasis from gastric cancer is dismal. This article reviews the characteristics of gastric cancer metastasizing to the liver, and multimodality of treatments. Differentiated adenocarcinoma, poorly differentiated adenocarcinoma with a medullary growth pattern, and special types, including endocrine carcinoma and hepatoid carcinoma, are likely to metastasize to the liver. The overexpression of growth factors or adhesion molecules is clinically significant for liver metastasis. Surgery for liver metastases arising from gastric adenocarcinoma is reasonable if a complete resection seems feasible after careful preoperative staging. A hepatic resection should always be considered as an option for gastric cancer patients with hepatic metastases. Newer generation cytotoxic agents such as S-1, irinotecan, and taxanes show promising activity for patients with metastases. Adjuvant chemotherapy or molecular targeted therapy will provide significant benefits to patients in the future.

Hepatocellular oncofetal protein, glypican 3 is a sensitive marker for alpha-fetoprotein-producing gastric carcinoma

AIMS

Glypican 3 (GPC3) is a cell surface heparan sulphate proteoglycan expressed specifically in the fetal liver and malignant neoplasms of hepatocyte lineage. The aim was to evaluate the significance of GPC3 in alpha-fetoprotein (AFP)-producing gastric carcinoma (GC) and other forms of GC.

METHODS AND RESULTS

We immunohistochemically evaluated GPC3 expression in representative cases of AFP-producing GC and in a tissue microarray of a consecutive series of GCs with other markers of hepatocyte lineage (AFP, PIVKA-II and hepatocyte antigen, HEP). In a series of 10 cases of AFP-producing GC, we observed immunohistochemical positivity for GPC3, PIVKA-II and HEP in 10, three and three cases in components with a hepatoid pattern and in nine, two and five cases in components with a non-hepatoid pattern, respectively. In a series of 118 cases of GC, we observed positivity for AFP, GPC3, PIVKA-II and HEP in one (0.8%), four (3.4%), six (5.1%) and 26 cases (22%), respectively. GPC3 was observed concurrently with AFP and discordantly with PIVKA-II and HEP. GPC3 positivity was clearly stronger in a larger area compared with immunoreactivity for AFP.

CONCLUSIONS

GPC3 is a sensitive marker for AFP-producing GC and its hepatoid component and is therefore useful to identify this aggressive subgroup of GC.

Collecting duct carcinoma of kidney producing alpha-fetoprotein

AIM

A case of a collecting duct carcinoma (CDC) of the kidney alpha-fetoprotein producing is reported. Serum elevation of alpha-fetoprotein (AFP) is a common marker for hepatocellular carcinoma, although some extrahepatic carcinomas, also of the kidney, with elevated AFP levels have also been reported in the literature.

CASE REPORT

A 62-year-old man with a collecting duct carcinoma of the kidney presenting as a mediastinal mass and supra-clavicular lymph node enlargement, and with a serum alpha-fetoprotein (AFP) level of 102.8 microg/L.

RESULTS AND CONCLUSIONS

CDC of the kidney is associated with an aggressive course and extremely poor prognosis. There are no standard treatment regimens, and neither immunotherapy nor chemotherapy has been found to be effective. In the present case, nephrectomy followed by a chemotherapeutic association of carboplatin and gemcitabine gave promising results, with lessening of the patient's symptoms.