[Retracted] Alteration of p53-binding protein 1 expression as a risk factor for local recurrence in patients undergoing resection for extrahepatic cholangiocarcinoma.

Following the publication of this paper, the Journal was alerted by an investigation committee of Niigata University to the fact that the paper had been identified as a duplicate publication, which had already been published. Therefore, in accordance with the rules of Niigata University Fraud Investigation committee, a request was made that the paper be retracted. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in International Journal of Oncology 38: 1227-1236, 2011; DOI: 10.3892/ijo.2011.959].

Alteration of the DNA damage response in colorectal tumor progression.

Recent studies have demonstrated increased levels of DNA double-strand breaks (DSBs) and activation of the DNA damage response (DDR) in precancerous lesions during cancer development. Those observations have not been fully elucidated using paraffin-embedded tissues of colorectal tumors. The aims of this study were to analyze the presence of DSBs and DDR activation mediated by p53-binding protein 1 (53BP1), which is a conserved checkpoint and DNA repair protein, and to clarify their association with colorectal tumor progression. We used immunohistochemical staining to investigate the expression of γH2AX, a sensitive marker for DSBs, in 152 colorectal tumors (46 low-grade adenomas, 25 high-grade adenomas, 25 intramucosal carcinomas, and 56 invasive carcinomas). The colocalization of γH2AX and 53BP1, which is strongly associated with the DSB repair process, was analyzed using double-label immunofluorescence. Elevated γH2AX expression was identified in 16 (16.7%) of 96 intramucosal neoplasias and in 19 (33.9%) of 56 invasive carcinomas. Double-label immunofluorescence occasionally revealed cells, particularly in invasive carcinoma, with γH2AX foci that did not colocalize with 53BP1. The percentage of tumor cells with γH2AX foci that colocalized with 53BP1 was significantly lower in invasive carcinoma than in intramucosal neoplasia (median percentage, 54.8% and 88.5%, respectively; P = .001). In conclusion, the number of cells with DSBs increases in intramucosal neoplasia and invasive carcinoma. The decreasing number of cells with colocalization of γH2AX and 53BP1 during the progression from intramucosal neoplasia to invasive carcinoma suggests that DDR, at least mediated by 53BP1, is inefficient during the process of cancer invasion.

Early DNA damage response in residual carcinoma in situ at ductal stumps and local recurrence in patients undergoing resection for extrahepatic cholangiocarcinoma.

BACKGROUND/PURPOSE: The aim of this study was to clarify the association between the DNA damage response mediated by p53-binding protein 1 (53BP1) in residual carcinoma in situ at ductal stumps and local recurrence in patients undergoing resection for extrahepatic cholangiocarcinoma. METHODS: A retrospective analysis was conducted of 11 patients with positive ductal margins with carcinoma in situ. To evaluate the early DNA damage response, the nuclear staining pattern of 53BP1 was examined by immunofluorescence. TUNEL analysis was used to calculate the apoptotic index. RESULTS: Of the 11 tumor specimens of carcinoma in situ, seven showed diffuse localization of 53BP1 in nuclei (53BP1 inactivation) and four showed discrete nuclear foci of 53BP1 (53BP1 activation); the apoptotic index was significantly decreased in the seven tumor specimens with 53BP1 inactivation compared to the four with 53BP1 activation (median apoptotic index, 1 vs. 22 %; p = 0.003). The cumulative probability of local recurrence was significantly higher in patients with 53BP1 inactivation than in patients with 53BP1 activation (cumulative 5-year local recurrence rate, 60 vs. 0 %; p = 0.019). CONCLUSIONS: Clinically evident local recurrence of residual carcinoma in situ at ductal stumps is closely associated with 53BP1 inactivation and decreased apoptosis.

Ribonucleotide reductase M1 expression in intrahepatic cholangiocarcinoma.

BACKGROUND/AIMS: Ribonucleotide reductase M1 (RRM1) is a key molecule for gemcitabine resistance. This study evaluated the immunohistochemical expression of RRM1 in resected specimens of intrahepatic cholangiocarcinoma (ICC) and investigated the efficacy of gemcitabine-based neoadjuvant chemotherapy in relation to RRM1 expression in tumors. METHODOLOGY: A retrospective analysis was conducted on 34 consecutive Japanese patients who underwent resection of ICC. Of the 34 patients, 2 were treated with neoadjuvant chemotherapy consisting of gemcitabine 800mg/m2 every 2 weeks to address extrahepatic tumor extension. Expression of RRM1 in tumor specimens was assessed using immunohistochemistry and was classified as either positive or negative. RESULTS: RRM1-positive expression was detected in 19/34 (56%) tumor specimens. Two patients were treated with gemcitabine-based neoadjuvant chemotherapy; one had a tumor specimen showing RRM1-positive expression and showed a 14% tumor reduction rate (stable disease); another patient had a tumor showing RRM1-negative expression and showed a 68% tumor reduction rate (partial response). Surgical procedures planned before administration of neoadjuvant chemotherapy were performed in both patients. CONCLUSIONS: Neoadjuvant chemotherapy with gemcitabine for locally advanced ICC was well tolerated and did not impair planned surgical resections. Tumor expression of RRM1 may determine the efficacy of gemcitabine-based chemotherapy for patients with ICC.

Intraepithelial ductal spread in colorectal carcinoma liver metastasis.

BACKGROUND/AIMS: This study aimed to evaluate the usefulness of immunohistochemical combinations for discrimination between intraepithelial ductal spread of colorectal carcinoma liver metastasis (CRLM) and that of intrahepatic cholangiocarcinoma (ICC). METHODOLOGY: A retrospective analysis of resected specimens from 151 patients with CRLM and 28 patients with ICC was conducted. Intraepithelial ductal spread along the bile ducts was judged positive when tumor cells spreading along the intact basement membranes of intrahepatic bile ducts. We evaluated immunoreactivity of cytokeratin (CK) 7, CK20, CDX2, MUC2, MUC5AC and human gastric mucin (HGM). RESULTS: Of the 151 patients with CRLM, 21 had intrahepatic bile duct involvement verified histologically. Intraepithelial ductal spread was detected in 17 of 21 (81%) patients with CRLM with bile duct involvement, whereas it was detected in 22 of 28 (79%) patients with ICC. CK20-positive/ CK7-negative immunophenotype demonstrated a high accuracy of 95% for evaluation of intraepithelial ductal spread from CRLM. CK7-positive/ CK20-negative immunophenotype demonstrated the highest accuracy of 85% for evaluation of intraepithelial ductal spread from ICC. CONCLUSION: Intraepithelial ductal spread is a common feature of CRLM with bile duct involvement. Immunohistochemical combination of CK7 and CK20 is useful for discrimination between intraepithelial ductal spread of CRLM and that of ICC.

Prognostic significance of NQO1 expression in intrahepatic cholangiocarcinoma.

This study aimed to evaluate the association between the immunohistochemical expression of NAD(P) H:quinone oxidoreductase-1 (NQO1) and nuclear factor erythroid 2-related factor 2 (Nrf2) in resected specimens of intrahepatic cholangiocarcinoma (ICC) and to elucidate the prognostic value of NQO1 and Nrf2 expression. A retrospective analysis was conducted of 34 consecutive patients who underwent surgical resection for ICC. Immunohistochemistry of the resected specimens was conducted using each of the following primary monoclonal antibodies against NQO1 and Nrf2. Of the 34 patients, 23 were classified as having tumors with NQO1-positive expression and 11 had tumors with loss of NQO1 expression, whereas 22 patients had tumors with Nrf2-positive expression and 12 had tumors with loss of Nrf2 expression. NQO1 expression showed a positive association with Nrf2 expression (p=0.005). Loss of NQO1 expression was more frequent in tumor specimens that were moderately or poorly differentiated (11/26; 42%) than in well-differentiated tumors (0/8; 0%; p=0.034). Post-resection survival was significantly worse in patients with tumors with loss of NQO1 expression than in patients with NQO1-positive tumors (cumulative 5 -year survival rate of 0% and 51%, respectively; p=0.005). Nrf2 expression was not associated with survival after resection (p=0.287). The Cox proportional hazards regression analysis revealed that lymph node involvement (p<0.001) and loss of NQO1 expression (p<0.001) had an independent adverse effect on survival. Loss of NQO1 expression reflects dedifferentiation and thus indicates a poor prognosis for patients undergoing resection for ICC.

Alteration of p53-binding protein 1 expression as a risk factor for local recurrence in patients undergoing resection for extrahepatic cholangiocarcinoma.

P53-binding protein 1 (53BP1) is an early DNA damage response-protein that is rapidly recruited to sites of DNA double-strand breaks. The presence of 53BP1 nuclear foci can be considered as a cytologic marker for endogenous double-strand breaks reflecting genomic instability. This study aimed to clarify the early DNA damage response mediated by 53BP1 in tumor specimens of ductal resection margins and to elucidate its predictive value for clinically evident local recurrence at ductal stumps in 110 patients undergoing resection for extrahepatic cholangiocarcinoma. The ductal resection margin status was classified as negative (85 patients), positive with carcinoma in situ (14 patients), or positive with invasive carcinoma (11 patients). The nuclear staining pattern of 53BP1 was evaluated by immunofluorescence. TUNEL analysis was used to calculate apoptotic index. Ductal margin status was the only independent risk factor for local recurrence (P=0.001). The cumulative probability of local recurrence at 5 years was 10%, 40% and 100% in patients with negative ductal margins, positive with carcinoma in situ and positive with invasive carcinoma, respectively (P<0.001). Of the 14 tumor specimens of carcinoma in situ, 10 showed diffuse localization of 53BP1 in nuclei (53BP1 inactivation) and 4 showed discrete nuclear foci of 53BP1 (53BP1 activation). All 11 tumor specimens of invasive carcinoma showed 53BP1 inactivation. Apoptotic index was markedly decreased in tumor specimens with 53BP1 inactivation compared to those with 53BP1 activation (median index, 0% vs. 22%; P<0.001). Among 14 patients with residual carcinoma in situ, the cumulative probability of local recurrence was significantly higher in patients with 53BP1 inactivation than in patients with 53BP1 activation (60% vs. 0% at 5 years; P=0.020). In conclusion, after resection for extrahepatic cholangiocarcinoma, clinically evident local recurrence at ductal stumps is closely associated with 53BP1 inactivation and decreased apoptosis.

Gastric Ewing sarcoma/primitive neuroectodermal tumor: A case report.

Ewing sarcoma/primitive neuroectodermal tumors (ES/PNETs) may arise in bone or soft tissue; however, these tumors rarely originate in the stomach. To the best of our knowledge, only four cases have previously been reported in the English-language literature. A 41-year-old Japanese woman was admitted with abdominal pain and underwent gastrectomy to remove the primary tumor. Immunohistochemistry, chromosomal karyotype and molecular analysis using reverse transcription-polymerase chain reaction were performed in the tumor specimens obtained. Tumor cells showed positive immunoreactivity for CD99, vimentin, CD117 (c-kit), S100, chromogranin A and synaptophysin. The tumor was a gastric ES/PNET with the EWS-FLI1 fusion gene translocation t(11;22)(q24;q12). Multiple repeat metastasectomies, as well as multi-agent chemotherapy and radiotherapy were performed for recurrent disease. Despite treatment, the patient succumbed due to progressive disease 110 months after the initial surgery for gastric ES/PNET. A review of the reported cases suggests that patients with gastric ES/PNETs have an unfavorable prognosis following resection due to the high propensity of these tumors to metastasize. Thus, multimodal treatment approaches including surgery, as well as multi-agent chemotherapy and radiotherapy may provide a survival benefit for patients with gastric ES/PNETs.

Clinical significance of intracapsular and extratumoral venous invasion in hepatocellular carcinoma.

BACKGROUND/AIMS: The current study sought to clarify whether intracapsular venous invasion and extratumoral venous invasion confer different prognostic significance in patients undergoing hepatectomy for hepatocellular carcinoma. METHODOLOGY: A retrospective study of 275 consecutive patients who underwent hepatectomy for hepatocellular carcinoma was conducted. Extratumoral venous invasion was defined as gross or microscopic involvement of vessels within the peritumoral liver tissue, whereas intracapsular venous invasion was defined as microscopic involvement of vessels within the fibrous tumor capsule. The median follow-up time was 64 months. RESULTS: Vascular invasion was found in 104 (38%) of the 275 patients. Intracapsular venous invasion was present in 16 patients and extratumoral venous invasion observed in 88 patients. Overall cumulative survival rates were 64% at 5 years and 45% at 10 years. Vascular invasion was a strong prognostic factor by univariate (p = 0.0001) and multivariate (p = 0.006) analyses. Survival after hepatectomy was significantly worse in patients with extratumoral venous invasion (cumulative 10-year survival rate of 28%) than in patients with intracapsular venous invasion (cumulative 10-year survival rate of 70%; p = 0.0082). CONCLUSIONS: Extratumoral venous invasion adversely influences survival after hepatectomy for hepatocellular carcinoma compared to intracapsular venous invasion.

Aberrant expression of vimentin correlates with dedifferentiation and poor prognosis in patients with intrahepatic cholangiocarcinoma.

BACKGROUND: This study aimed to elucidate the prognostic value of vimentin expression in patients with intrahepatic cholangiocarcinoma (ICC). PATIENTS AND METHODS: A retrospective analysis of 21 patients who underwent resection for ICC was conducted. Vimentin expression was positive when single tumour cells or cell clusters showed immunoreactivity to vimentin, whereas vimentin-negative expression was defined as no detectable expression. RESULTS: Of the 21 patients, 5 were classified as having tumours with vimentin-positive expression and 16 with vimentin-negative expression. Vimentin-positive expression was more frequent in tumour specimens that were poorly differentiated (4/7; 57%) than in those that were well- or moderately differentiated (1/14; 7%, p=0.025) and was always seen in areas with the highest histological grade. Vimentin-positive expression affected survival adversely, according to univariate (p=0.010) and multivariate analyses (relative risk, 4.294; p=0.047). CONCLUSION: Vimentin-positive expression correlates with dedifferentiation and predicts poor survival in patients undergoing resection for ICC.

Multidrug resistance-associated protein 2 determines the efficacy of cisplatin in patients with hepatocellular carcinoma.

We hypothesized that expression of multidrug resistance-associated protein 2 (MRP2), a major cisplatin transporter, may determine the efficacy of cisplatin as a treatment for patients with hepatocellular carcinoma (HCC). A prospective analysis was conducted of 49 consecutive patients who underwent resection for HCC (16 patients treated with cisplatin-based neoadjuvant chemotherapy and 33 patients treated without neoadjuvant chemotherapy). Expression of MRP2 in resected specimens was assessed by immunohistochemical and Western blot analyses. The extent of tumor necrosis was assessed histologically in the greatest dimension of the tumor specimen from each patient. The median percentage of tumor necrosis was 81% (range: 0-100%) and complete tumor necrosis was found in 3 patients. Overexpression of MRP2 was detected in 24/46 (52%) tumor specimens. In 16 patients treated with cisplatin, tumor size and dose of cisplatin did not correlate with tumor necrosis of the resected specimens (P=0.706 and P=0.555, respectively). Of 13 tumor specimens containing vivid tumor from 16 patients treated with cisplatin, 8 had overexpression of MRP2. Tumor specimens with overexpression of MRP2 showed a lower percentage of tumor necrosis than those with non-overexpression (median percentage of tumor necrosis, 19% vs. 99%, P=0.003). In conclusion, overexpression of MRP2 correlates with a lower percentage of tumor necrosis in patients treated with cisplatin-based neoadjuvant chemotherapy for HCC, whereas either tumor size or dose of cisplatin does not. Expression of MRP2 determines the efficacy of cisplatin-based chemotherapy in patients with HCC.

Histological evaluation of intracapsular venous invasion for discrimination between portal and hepatic venous invasion in hepatocellular carcinoma.

BACKGROUND AND AIM: Histological criteria for intracapsular venous invasion (IVI) that would allow its discrimination between portal and hepatic venous invasion in hepatocellular carcinoma (HCC) have not been established. METHODS: We evaluated IVI immunohistochemically to discriminate between portal and hepatic venous invasion in 89 resected specimens from patients with HCC. IVI was defined as the microscopic involvement of the vessels within the fibrous capsule of HCC. The hepatic venous system was subdivided into the central vein and the sublobular/hepatic vein. Immunohistochemical analysis with the D2-40 monoclonal antibody revealed lymphatic vessels. RESULTS: In non-neoplastic liver tissues, the portal veins (n = 4355) were accompanied by lymphatic vessels (99.7%), bile ductules (100%) and arteries (96%), whereas the central veins (n = 3932) and sublobular/hepatic veins (n = 662) were rarely accompanied by lymphatic vessels (0% and 17%, respectively) and bile ductules (12% and 33%, respectively). In total, 29 IVI foci were detected; three foci were clearly visible within vessels that contained a distinct layer of connective tissue fibers, signifying sublobular/hepatic venous invasion. As the remaining 26 foci were accompanied by lymphatic vessels (26/26 [100%]), bile ductules (21/26 [81%]) and arteries (10/26 [38%]), these foci were considered to reflect intracapsular portal venous invasion rather than venous invasion of the central vein. Intracapsular portal venous invasion was significantly associated with extratumoral portal venous invasion (P < 0.001). CONCLUSIONS: D2-40 immunoreactivity for the histological evaluation of IVI in HCC allows discrimination between portal and hepatic venous invasion for cases in which portal venous invasion predominates.

Loss of carcinoembryonic antigen-related cell adhesion molecule 1 expression predicts metachronous pulmonary metastasis and poor survival in patients with hepatoblastoma.

PURPOSE: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is a member of the carcinoembryonic antigen family of immunoglobulin-like adhesion molecules. The aim of this study was to test the hypothesis that loss of CEACAM1 expression in hepatoblastoma cells may promote hematogeneous metastasis and function as an adverse prognostic factor. METHODS: Immunohistochemical expression of CEACAM1 in surgically resected specimens from 19 patients with hepatoblastoma was examined retrospectively. The CEACAM1 expression in the epithelial area of the tumor was classified into 2 categories as follows: diffuse expression, characterized by positive staining throughout the tumor specimen, or loss of expression, in which there were distinct areas of negative staining within the tumor specimen. RESULTS: Of the 19 patients, 12 were classified as having tumors with diffuse expression, and 7 had loss-of-expression tumors. Survival after treatment was significantly worse in patients with tumors with loss of CEACAM1 expression (cumulative 5-year survival rate, 29%) than in patients with diffuse CEACAM1 expression (cumulative 5-year survival rate, 92%; P = .0062). Loss of CEACAM1 expression was a significant risk factor for metachronous pulmonary metastases (P = .0105). CONCLUSIONS: Loss of CEACAM1 expression may reflect a high metastatic potential and thus indicate a poor prognosis for patients with hepatoblastoma.

Overexpression of osteopontin independently correlates with vascular invasion and poor prognosis in patients with hepatocellular carcinoma.

This study retrospectively evaluated the immunohistochemical expression of 3 cell adhesion molecules (CAMs), E-cadherin, beta-catenin, and osteopontin, according to tumor grade in 125 surgically resected specimens of hepatocellular carcinoma (HCC). The aims of this study were to identify factors associated with vascular invasion and to elucidate the prognostic value of CAMs. The median follow-up time was 110 months. The levels of E-cadherin, beta-catenin, and osteopontin immunoreactivity were significantly associated with Edmondson-Steiner grade but not with tumor size. There was increased loss of E-cadherin, nonnuclear overexpression of beta-catenin, and overexpression of osteopontin in tumors of higher histologic grade. Vascular invasion was found in 44 (35%) of 125 resected specimens. Logistic regression analysis identified 3 tumor-related factors that were independently associated with vascular invasion-tumor size more than 3 cm, Edmondson-Steiner grades III to IV, and overexpression of osteopontin. Among the tested CAMs, osteopontin (P = .0110) and E-cadherin (P = .0287) were significant prognostic factors by univariate analysis. The Cox proportional hazard regression analysis revealed that Edmondson-Steiner grades III to IV (relative risk [RR], 3.028; P < .001), the presence of vascular invasion (RR, 1.964; P = .011), overexpression of osteopontin (RR, 1.755; P = .034), serum alpha-fetoprotein level more than 20 ng/mL (RR, 1.834; P = .037), and Child-Pugh classification B to C (RR, 1.880; P = .040) were found to be independently significant factors associated with survival after hepatectomy. These results suggest that overexpression of osteopontin independently correlates with vascular invasion and thus predicts poor survival for patients with HCC, whereas aberrant expression of E-cadherin or beta-catenin does not.

Appraisal of 1 cm hepatectomy margins for intrahepatic micrometastases in patients with colorectal carcinoma liver metastasis.

BACKGROUND: This study sought to clarify the distribution of intrahepatic micrometastases and elucidate an adequate hepatectomy margin for colorectal carcinoma liver metastases. METHODS: Intrahepatic micrometastases in resected specimens from 90 patients who underwent hepatectomy for colorectal carcinoma liver metastases were examined retrospectively. Intrahepatic micrometastases were defined as microscopic lesions spatially separated from the gross tumor. Distances from these lesions to the hepatic tumor borders were measured histologically, and the density of intrahepatic micrometastases (number of lesions/mm(2)) calculated relative to the advancing tumor border in a zone <1 cm from the border (close) or >/=1 cm away (distant). Median follow-up time was 127 months. RESULTS: A total of 294 intrahepatic micrometastases were detected in 52 (58%) patients; 95% of these occurred in the close zone. The density of intrahepatic micrometastases was significantly higher in the close zone (mean 74.8 x 10(-4 ) lesions/mm(2)) than in the distant zone (mean 7.4 x 10(-4 ) lesions/mm(2); P < 0.001). Hepatectomy margin status was positive by 0 cm in 10 patients or negative by <1 cm in 51, and by >/=1 cm in 29 patients. The median survival times were 18, 33, and 89 months in patients with hepatectomy margins 0 cm, <1 cm, and >/=1 cm, respectively. Hepatectomy margin status independently influenced survival (P < 0.001) and disease-free survival (P < 0.001). CONCLUSION: The currently recommended >/=1 cm hepatectomy margin should remain the goal for resections of colorectal carcinoma liver metastases, based on the distribution of intrahepatic micrometastases and survival risk.

Intrahepatic lymphatic invasion independently predicts poor survival and recurrences after hepatectomy in patients with colorectal carcinoma liver metastases.

BACKGROUND: D2-40 monoclonal antibody immunoreactivity is specific for lymphatic endothelium and therefore provides a marker of lymphatic invasion. We hypothesized that intrahepatic lymphatic invasion reflects the nodal status of colorectal carcinoma liver metastases and may function as an adverse prognostic factor. METHODS: A retrospective analysis of 105 consecutive patients who underwent resection for colorectal carcinoma liver metastases was conducted. Intrahepatic lymphatic invasion was declared when either single tumor cells or cell clusters were clearly visible within vessels that showed immunoreactivity for D2-40 monoclonal antibody. The median follow-up time was 124 months. RESULTS: Of 105 patients, 13 were classified as having intrahepatic lymphatic invasion. All tumor foci of intrahepatic lymphatic invasion were detected within the portal tracts. Intrahepatic lymphatic invasion was significantly associated with hepatic lymph node involvement (P = 0.039). Survival after resection was significantly worse in patients with intrahepatic lymphatic invasion (median survival time of 13 months; cumulative five-year survival rate of 0%) than in patients without (median survival time of 40 months; cumulative five-year survival rate of 41%; P < 0.0001). Patients with intrahepatic lymphatic invasion also showed decreased disease-free survival rates (P < 0.0001). Intrahepatic lymphatic invasion thus independently affected both survival (relative risk, 7.666; 95% confidence interval, 3.732-15.748; P < 0.001) and disease-free survival (relative risk, 4.112; 95% confidence interval, 2.185-7.738; P < 0.001). CONCLUSIONS: Intrahepatic lymphatic invasion is associated with hepatic lymph node involvement and is an adverse prognostic factor in patients with colorectal carcinoma liver metastases.