Radical lymph node dissection and assessment:Impact on gallbladder cancer prognosis

AIM: To investigate the lymph node metastasis patterns of gallbladder cancer(GBC) and evaluate the optimal categorization of nodal status as a critical prognostic factor.METHODS: From May 1995 to December 2010,a total of 78 consecutive patients with GBC underwent a radical resection at Liaocheng People's Hospital.A radical resection was defined as removing both the primary tumor and the regional lymph nodes of the gallbladder.Demographic,operative and pathologic data were recorded.The lymph nodes retrieved were examined histologically for metastases routinely from each node.The positive lymph node count(PLNC) as well as the total lymph node count(TLNC) was recorded for each patient.Then the metastatic to examined lymph nodes ratio(LNR) was calculated.Disease-specific survival(DSS) and predictors of outcome were analyzed.RESULTS: With a median follow-up time of 26.50 mo(range,2-132 mo),median DSS was 29.00 ± 3.92 mo(5-year survival rate,20.51%).Nodal disease was found in 37 patients(47.44%).DSS of node-negative patients was significantly better than that of nodepositive patients(median DSS,40 mo vs 17 mo,χ2= 14.814,P < 0.001),while there was no significant difference between N1 patients and N2 patients(median DSS,18 mo vs 13 mo,χ2= 0.741,P = 0.389).Optimal TLNC was determined to be four.When node-negative patients were divided according to TLNC,there was no difference in DSS between TLNC < 4 subgroup and TLNC ≥ 4 subgroup(median DSS,37 mo vs 54 mo,χ2 = 0.715,P = 0.398).For node-positive patients,DSS of TLNC < 4 subgroup was worse than that of TLNC ≥ 4 subgroup(median DSS,13 mo vs 21 mo,χ2= 11.035,P < 0.001).Moreover,for node-positive patients,a new cut-off value of six nodes was identified for the number of TLNC that clearly stratified them into 2 separate survival groups(< 6 or ≥ 6,respectively;median DSS,15 mo vs 33 mo,χ2= 11.820,P < 0.001).DSS progressively worsened with increasing PLNC and LNR,but no definite cut-off value could be identified.Multivariate analysis revealed histological grade,tumor node metastasis staging,TNLC and LNR to be independent predictors of DSS.Neither location of positive lymph nodes nor PNLC were identified as an independent variable by multivariate analysis.CONCLUSION: Both TLNC and LNR are strong predictors of outcome after curative resection for GBC.The retrieval and examination of at least 6 nodes can influence staging quality and DSS,especially in nodepositive patients.

Breeding and preliminarily phenotyping of a congenic mouse model with alopecia areata

In the current study, the alopecia areata gene was introduced into the C57BL/6 （B6） mouse through repeated backcrossing/intercrossing, and the allelic homozygosity of congenic AAtJmice （named B6.KM-AA） was verified using microsatellites. The gross appearance, growth characteristics, pathological changes in skin, and major organs of B6.KM-AA mice were observed. Counts and proportions of CD4＋ and CD8＋ T lymphocytes in peripheral blood were determined by flow cytometry. Results show that congenic B6.KM-AA mice were obtained after 10 generations of backcrossing/intercrossing. B6.KM-AA mice grew slower than B6 control mice and AA skin lesions were developed by four weeks of age. The number of hair follicles was reduced, but hair structures were normal. Loss of hair during disease progression was associated with CD4＋ and CD8＋ T lymphocytes infiltration peri- and intrahair follicles. No pathological changes were found in other organs except for the skin. In the peripheral blood of B6.KM-AA mice, the percentage of CD4＋ T cells was lower and percentage of CD8＋ T cells higher than in control mice. These findings indicate that B6.KM-AA mice are characterized by a dysfunctional immune system, retarded development and T-cell infiltration mediated hair loss, making them a promising new animal model for human alopecia areata.