Determination factors of patients' decision between surgery and chemoradiotherapy for stage I esophageal carcinoma: From the results of JCOG0502—A comparative study of the two modalities

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Background: Surgery is the standard of care for stage I esophageal squamous cell carcinoma. However, definitive chemoradiothearpy (CRT) is optional treatment which can preserve organ function with cure. The aim of this study was to investigate what factors have influence patients(pts)’ decision on the treatment, surgery or CRT. Methods: JCOG0502 is a randomized controlled trial comparing surgery to CRT. Sufficient information about both treatments was provided for pts before enrollment. Pts who declined to participate in randomized part can choose a preferred treatment and join a non-randomized part of JCOG0502. Between Dec 2006 and Feb 2013, 379 pts were enrolled to JCOG0502 from 37 institutions of Japan Clinical Oncology Group. Among those, 368 pts who enrolled to non-randomized part were analyzed. Clinical baseline data, social data and doctor’s preference which was not mandatory informed to patients were collected on the case report forms and compared between surgery arm and CRT arm. Preference of doctors for each pt was divided into three categories, A: “surgery is preferred”, B: “either is adequate” and C: “CRT is preferred”. This trial was registered as UMIN000000551. Logistic regression were performed to evaluate the influence of each factors. Results: Of the 368 pts, 209 pts chose surgery with their own intention, while 159 pts chose CRT. There were no differences on baseline clinical characteristics between two groups except median age (Surgery: CRT = 62:65 years). Multivariate logistic regression analyses showed that >=65 years (vs<65) (OR 2.04, p=0.006), male (vs female) (OR 2.10, p=0.043), multi-focal primary (vs single) (OR 2.76, p=0.013), status of patient’s children (vs presence of children) (absence of children: OR 2.27, p=0.034) (unknown: OR 4.422, p=0.13), and B or C category of preference of the doctor (vs A) (B:OR 11.67, p<0.001)(C:HR 29.64, p<0.001) were associated with selection of CRT. Conclusions: Older age, male, multifocal primary, absence of children and doctor’s preference are independent factor to choose CRT. Doctor’s preference to each pt was the strongest factor on decision making of patients.

Hand-sewn anastomotic technique after esophageal cancer resection

BACKGROUND/AIMS

Mechanical stapled anastomosis can be performed easily and quickly in esophagogastrostomy after esophageal cancer resection. However, we have performed cervical hand-sewn anastomosis in the esophagogastrostomy. Here we introduce the surgical technique and report the outcomes after the anastomosis.

METHODOLOGY

The gastric tube is pulled up via the posterior mediastinal route. A single layer of Gambee sutures is used to approximate the cervical esophagus and the posterior wall of the gastric tube in end-to-side fashion. After the anastomosis, the redundant part in the gastric tube apex is removed. We analyzed 152 consecutive patients who underwent this anastomosis in our institute from 1999 to 2012.

RESULTS

There was no postoperative mortality. We experienced anastomotic leakage in 7 patients (5%) and anastomotic stenosis in 5 patients (3%).

CONCLUSIONS

The anastomotic complication rates in the hand-sewn anastomosis were comparable to those of the mechanical stapled anastomosis in the previous reports.

Safety profile of thoracoscopic esophagectomy for esophageal cancer compared with traditional thoracotomy from the results of JCOG0502: A randomized trial of esophagectomy versus chemoradiotherapy

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Background: Esophagectomy for esophageal cancer via the thoracoscopic approach (TA) is expected to reduce the extent of trauma compared with traditional thoracotomy (TT). However, there have been few prospective studies comparing perioperative complications between TA and TT after esophagectomy. Therefore, this study aimed to clarify whether TA is a safe procedure with regard to morbidity and mortality using the data of patients (pts) who underwent esophagectomy in the JCOG0502 trial. Methods: The JCOG0502 trial is a currently on-going randomized trial including a patient preference arm of esophagectomy versus chemoradiotherapy for treatment of clinical stage I esophageal cancer. The primary analysis of overall survival is planned in 2018. In this trial, thoracic squamous cell carcinoma, adenosquamous carcinoma, and basaloid carcinoma of stage T1b/N0/M0 were eligible. When pts were randomized to surgery or selected surgery, esophagectomy with D2–3 lymphadenectomy was performed. TA or TT was selected at the surgeon’s discretion. Perioperative complications were defined as adverse events of grade 2 or greater as per CTCAE v3.0. Results: A total of 379 pts (11 randomized and 368 in the patient preference arm) were enrolled between December 2006 and February 2013 from 37 institutions, and 211 pts underwent surgery. Of these 211 pts, TA was performed in 101 pts while TT was performed in 110 pts. Blood loss was less in the TA group than in the TT group (median, 293 vs. 410 mL, respectively), and the surgical duration was longer in the TA group than in the TT group (median, 510 vs. 398 min). The proportion of intraoperative complications was similarly low in both groups. However, postoperative anastomotic leakage, pneumonia, and atelectasis were less common in the TA group than in the TT group (7%, 8%, and 11% vs. 14%, 17%, and 22%). Moreover, the proportion of recurrent nerve palsy was similar among both groups (15% vs. 16%). Each group had one in-hospital death. Conclusions: This study indicated that TA did not increase morbidity or mortality after esophagectomy and can be safely performed with risks comparable to those with TT. Clinical trial information: UMIN000000551.

Incidence of metachronous gastric cancer in the remnant stomach after synchronous multiple cancer surgery

BACKGROUND

In the preoperative evaluation for gastric cancer, high-resolution endoscopic technologies allow us to detect small accessory lesions. However, it is not known if the gastric remnant after partial gastrectomy for synchronous multiple gastric cancers has a greater risk for metachronous cancer. The purpose of this study was to determine the incidence of metachronous cancer in this patient subset compared with that after solitary cancer surgery.

METHODS

Data on a consecutive series of 1,281 patients gastrectomized for early gastric cancer from 1991 to 2007 were analyzed retrospectively. The 715 gastric remnants after distal gastrectomy were periodically surveyed by endoscopic examination in Shikoku Cancer Center. Among those surveyed cases, 642 patients were pathologically diagnosed with solitary lesion (SO group) and 73 patients with synchronous multiple lesions (MU group) at the time of the initial surgery.

RESULTS

In the follow-up period, 15 patients in the SO group and 3 patients in the MU group were diagnosed as having metachronous cancer in the gastric remnant. The cumulative 4-year incidence rate was 1.9 % in the SO group and 5.5 % in the MU group. The difference did not reach the significant level by the log-rank test.

CONCLUSIONS

The incidence of metachronous cancer is higher after multiple cancer surgery; however, the difference is not statistically significant.

Long-term outcome after proximal gastrectomy with jejunal interposition for gastric cancer compared with total gastrectomy

BACKGROUND

Proximal gastrectomy (PG) has been widely accepted as treatment for early gastric cancer located in the upper third of the stomach. Reconstruction by jejunal interposition has been known to reduce reflux esophagitis for PG patients. The aim of this study was to compare the long-term outcomes of patients who underwent PG with jejunal interposition with those treated by total gastrectomy (TG).

METHODS

Data on 102 cases of PG with jejunal interposition and 49 cases of TG with Roux-Y reconstruction for gastric cancer were analyzed retrospectively in terms of overall survival, weight maintenance, anemia and nutritional status, and endoscopic findings.

RESULTS

Median follow-up time was 59 months in the both groups. There was no significant difference in the overall 5-year survival rate between the PG group (94%) and the TG group (84%). The PG group showed significantly better body weight maintenance at the first year. The laboratory blood tests showed that the PG group had a significantly better red blood cell count and hemoglobin and hematocrit levels at the second and third year. However, postoperative endoscopic surveillance detected reflux esophagitis (3%), peptic ulcer (9%), and metachronous gastric cancer (5%) in the PG group.

CONCLUSIONS

Proximal gastrectomy maintains comparable oncological radicality to TG and is preferred over TG in terms of preventing postoperative anemia. However, periodic endoscopic follow-up is necessary to monitor the upper gastrointestinal tract.

Next study (JCOG1109): A three-arm randomized phase III study comparing preoperative CDDP+5-FU(CF) versus docetaxel+CF versus CF-radiation followed by esophagectomy with D2-3 lymphadenectomy for locally advanced esophageal squamous cell cancer

TPS4152

Background: Based on the results of JCOG9907, preoperative cisplatin plus 5- fluorouracil (CF) followed by esophagectomy with D2-3 lymphadenectomy has become standard care for advanced esophageal cancer in Japan, while the standard therapy in Western countries is preoperative chemoradiotherapy. A new clinical question has thus arisen of whether CF plus docetaxel (DCF) or CF plus radiotherapy (CF-RT) shows a survival benefit over preoperative CF even with intensive surgery. Methods: Eligibility criteria include histologically proven thoracic esophageal squamous cell carcinoma with stage IB/II/III (excluding T4) based on the 7th UICC-TNM, age 20 to 75, and performance status 0 to 1. No prior chemotherapy, radiotherapy, or hormonal therapy is allowed. Adequate organ function and written informed consent are required. Patients are randomized into any of the following three arms by a minimization method balancing the arms in terms of institution and tumor depth (T1–2 versus T3). Patients in arm A (CF) receive two courses of cisplatin at 80 mg/m2 on day 1 and fluorouracil at 800 mg/m2 on days 1–5, repeated every three weeks. Patients in arm B (DCF) receive three courses of docetaxel at 70 mg/m2, cisplatin at 70 mg/m2 on day 1, and fluorouracil at 750 mg/m2 on days 1–5, repeated every three weeks. Patients in arm C (CF-RT) receive two courses of cisplatin at 75 mg/m2 on day 1 and fluorouracil at 1000 mg/m2 on days 1–4, repeated every four weeks concurrently with radiotherapy at 41.4Gy/23fr. This trial is designed to demonstrate the superiority of preoperative DCF and/or CF-RT over CF in terms of overall survival. We assumed three-year survival with preoperative CF to be 63% and expected a 10% increase in three-year survival for DCF and CF-RT. The sample size was calculated as a total of 501 patients (167 patients per arm) with a study-wise one-sided alpha level of 5%, power of 70% for each pair comparison, an accrual period of 6.25 years, and a follow-up period of three years. This trial was registered as UMIN000009482 and started in December 2012. Clinical trial information: UMIN000009482.

[A case of reversible encephalopathy syndrome caused by hyponatremia during neoadjuvant 5-FU+CDDP therapy for esophageal cancer]

We present a case of reversible encephalopathy syndrome caused by hyponatremia during neoadjuvant chemotherapy with 5-FU+CDDP for esophageal cancer. A 52-year-old woman visited another hospital with the complaint of discomfort during swallowing. Upper gastrointestinal endoscopy revealed an ulcerated lesion in the lower thoracic esophagus, which was pathologically diagnosed as squamous cell carcinoma. She was admitted to our institution, and the diagnosis of esophageal cancer Mt-Lt, type 2, cT2N1M0, stage II was made. We obtained informed consent for her treatment with both CRT and surgery, and she selected surgery. Therefore, she was administered neoadjuvant chemotherapy with 5-FU+CDDP therapy. On day 4, abnormalities of the central nerve, such as unconsciousness, difficulty in speaking, and muscle cramps were, observed. After the examinations she was diagnosed with encephalopathy. It should be noted that hyponatremia induced by renal sodium wasting syndrome(RSWS)was considerd to be the cause, and we report our case with the literature cited.

Association between tuberculosis treatment outcomes and the mobile antiretroviral therapy programme in Zambia

SETTING

Free antiretroviral therapy (ART) services in Zambia were introduced in hospitals beginning in 2005 and in selected rural health centres (RHCs) beginning in 2007 through the mobile ART programme.

OBJECTIVE

To analyse the impact of scaling up ART services on tuberculosis (TB) treatment outcomes in Mumbwa District, Zambia.

DESIGN

TB patients registered at all RHCs in the district between July 2006 and September 2009 were reviewed. RHCs were divided into two groups: 'ART sites', which provided ART services after 2007, and 'non-ART sites', which did not provide such services even after 2007. A before-after comparison analysis of TB patients was conducted between the groups.

RESULTS

A total of 732 patients were enrolled (median age 34.5 years; female 44.4%). The overall human immunodeficiency virus (HIV) testing rate was 72.3% and 66.7% of these patients were HIV-positive. The TB treatment success rate at the ART sites increased significantly compared to non-ART sites after the mobile ART programme was started (P < 0.01). The HIV testing acceptance rate also increased dramatically at ART sites, which facilitated intensified case finding (P = 0.02).

CONCLUSION

Scaling up ART services in rural health facilities through the mobile ART programme was found to be associated with greatly improved anti-tuberculosis treatment outcomes.

A new technique for resecting gastric remnant cancer after proximal gastrectomy with jejunal interposition

Surgery for gastric remnant cancer after distal gastrectomy is well established; however, little is known about the removal of remnant gastric cancer following proximal gastrectomy with jejunal interposition. We introduce a surgical technique for removing remnant cancer under these circumstances. We used this technique to remove a total gastric remnant with radical lymph node dissection, while preserving the interposed jejunum for easy re-reconstruction by Roux-en-Y anastomosis, in five patients. The median operating time was 199 min and the median blood loss was 330 ml. There were no postoperative deaths or major complications and all five patients were discharged within 14 days after surgery. Our technique for total resection of the gastric remnant after proximal gastrectomy and re-reconstruction with preserved interposed jejunum is easy, safe, and effective.

Risk factors for metachronous gastric cancer in the remnant stomach after early cancer surgery

BACKGROUND

Early gastric cancer patients have a good prognosis after radical resection. However, if the patients have a gastric remnant after the surgery, the risk of metachronous gastric cancer remains. The aim of this study was to clarify the risk factors for metachronous gastric cancer after partial gastrectomy for early gastric cancer.

METHODS

Data on a series of 1281 consecutive gastrectomy patients with pathologically confirmed early gastric cancer from 1991 to 2007 in Shikoku Cancer Center were analyzed retrospectively.

RESULTS

The gastric remnants of 868 patients were periodically surveyed by endoscopic examination. Among those surveyed cases, 26 patients were diagnosed as having metachronous gastric cancer in the gastric remnant. They underwent curative resection by remnant gastrectomy (n = 13 patients) or endoscopic mucosal resection (n = 13 patients). Multivariate analysis showed that male sex, older age, submucosal invasion, and proximal gastrectomy were independent risk factors.

CONCLUSIONS

Our data suggested that more intensive endoscopic follow-up is needed for the remnant stomach in patients with these risk factors to detect metachronous gastric cancer at its early stage.

Abstract 2691: Prognostic significance of heat shock protein 90 expression in patients with advanced gastric cancer

Purpose: Heat shock protein 90 (HSP90) is a chaperone mediating the folding and stabilization of many oncoproteins. Considerable attention has been focused on the role of the HSP90 in the therapeutic strategy of molecular targeting HSP90. Recently it has reported that Trastuzumab, a recombinant monoclonal antibody against HER2, plus chemotherapy improved survival in HER2-positive gastric cancer patients. This study was designed to delineate the clinical implications of Hsp90 and HER2 immunoexpression in advanced gastric cancer.

Material and Methods: The study group comprised 47 patients who underwent gastrectomy at Shikoku Cancer Center Hospital excluding patients with stage I. According to the TNM classification, 18 tumors were identified as being stage II, 25 stage III, 4 stage IV. Using immunohistochemical techniques, we analyzed the expressions of HSP90 and HER2 on formalin-fixed paraffin-embedded specimens of surgically removed primary tumors. Immunostaining was graded as follows: low-HSP90 (defined as weaker staining compared with adjacent normal gastric mucosa), moderate-HSP90 (defined as equal), high-HSP90 (defined as stronger). HER2 expression was graded using a 4-point scale according to the criteria of HER2 membranous staining, which have been widely accepted. Chi-square test, Kaplan-Meier and Cox regression analysis were used for statistical analysis.

Results: Low-HSP90 expression was found in 13 tumors (28%) and HER2 high-expression (moderate to strong membrane staining in &gt; 10% of tumor cells) in 13 tumors (28%). Low-HSP90 was significantly detected in diffuse type (p = 0.0047) and was associated with clinicopathological parameters involved with tumor progression, including the depth of tumor invasion (p = 0.049) and advanced stage tumor (p = 0.029). Of note, High-HSP90 and HER2 overexpression (3+) were mutually exclusive (P=0.031). Kaplan-Meier survival analysis determined that tumors with low-HSP90 expression were statistically associated with worse disease-free survival (p = 0.036), and tended to detect poor postoperative survival (p = 0.084). Multivariate survival analysis showed that HSP90-negative expression [hazard ratio (HR) 3.05, 95% confidence interval (95% CI) 1.02-9.18; p = 0.046] and lymph node metastasis (HR 5.55; 95% CI 1.68-18.2; p = 0.005) were significant predictors of poor postoperative survival.

Conclusions: Our results indicate that low-HSP90 expression correlated with more aggressive disease and poor prognosis, and that HSP90 and HER2 overexpression might separately be molecular targets in gastric cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2691.

Esophagectomy via left thoracotomy for esophageal cancer with situs inversus totalis: report of a case

We report a case of successful esophagectomy via a left thoracotomy for esophageal cancer in a 57-year-old Japanese man with situs inversus totalis. An upper gastrointestinal endoscopy, performed to investigate the cause of dysphagia, revealed a 7-cm irregular shaped mass occupying more than half of the circumference of the middle-third of the esophagus. Computed tomography (CT) showed enlarged mediastinal lymph nodes and situs inversus totalis. Histological examination of a biopsy specimen revealed squamous cell carcinoma of the esophagus. Although esophagectomy is usually performed through a right thoracotomy because of the left position of the aortic arch, we performed successful subtotal esophagectomy with radical lymph node dissection through a left thoracotomy. During surgery, we modifi ed the standard surgical technique in a mirrorimage fashion to complete the esophagectomy safely. The patient had an uneventful postoperative course.

Laparoscopic colectomy for colorectal cancer patients with previous abdominal surgery

BACKGROUND/AIMS

Laparoscopic colectomy has been widely accepted as a standard operation for colorectal cancer. The use of this procedure for patients with previous abdominal surgery is now well established. The aim of this study was to evaluate the peri-operative and long-term outcomes of such patients, and to compare them to patients without previous surgery.

METHODOLOGY

Data on a consecutive 121 cases of laparoscopic colectomy performed for colorectal cancer from 1995-1999 in Shikoku Cancer Center were analyzed retrospectively for peri-operative and long-term outcomes.

RESULTS

Twenty one cases (17%) of laparoscopic colectomy were performed for colorectal cancer patients with previous surgery. Although the operation time for the previous surgery group was significantly longer than that of the control group, there was no significant difference in the peri-operative complications and the overall survival between the 2 groups.

CONCLUSIONS

Although the previous abdominal surgery increases the time it takes to perform the laparoscopic colectomy, the peri-operative and long-term outcomes were comparable to those from patients without previous surgery.

Higher incidence of gastric remnant cancer after proximal than distal gastrectomy

BACKGROUND/AIMS

Proximal gastrectomy has been widely accepted as a standard operation for early stage gastric cancer located in the upper third of the stomach. Therefore, cancer of the distal gastric remnant is now increasing. The aims of this study were to clarify and compare the incidences of gastric remnant cancer after proximal and distal gastrectomy.

METHODOLOGY

Data on a consecutive series of 809 cases of gastrectomy performed for early gastric cancer from 1991 to 2003 in Shikoku Cancer Center were analyzed retrospectively with respect to the incidence of gastric remnant cancer.

RESULTS

We performed distal gastrectomy in 624 patients and proximal gastrectomy in 47 patients during the study period. After those operations, the gastric remnants of 457 cases and 33 cases, respectively, were surveyed periodically by endoscopic examination at our hospital. Among those surveyed cases, 10 patients (2.2%) and 3 patients (9.1%) were diagnosed as having gastric remnant cancer, respectively. The gastric remnant cancer-free survival after proximal gastrectomy was significantly lower than that after distal gastrectomy.

CONCLUSIONS

Because of the higher incidence of gastric remnant cancer after proximal gastrectomy, it is more important to survey the gastric remnant after proximal gastrectomy periodically by postoperative endoscopic examination.

The MM2-cortical form of sporadic Creutzfeldt-Jakob disease presenting with visual disturbance

A subclass of sporadic Creutzfeldt-Jakob disease (sCJD) characterized by onset with visual symptoms (Heidenhain variant) has been reported to belong to the MM1 or MV1 type according to Parchi's classification. The authors report a 65-year-old woman with MM2-cortical sCJD with slowly progressive visual disturbance as the initial symptom. Diffusion-weighted MRIs revealed hyperintensity in both occipital cortices at an early stage.

Biliary wound healing, ductular reactions, and IL-6/gp130 signaling in the development of liver disease

Basic and translational wound healing research in the biliary tree lag significantly behind similar studies on the skin and gastrointestinal tract. This is at least partly attributable to lack of easy access to the biliary tract for study. But clinical relevance, more interest in biliary epithelial cell (BEC) pathophysiology, and widespread availability of BEC cultures are factors reversing this trend. In the extra-hepatic biliary tree, ineffectual wound healing, scarring and stricture development are pressing issues. In the smallest intra-hepatic bile ducts either impaired BEC proliferation or an exuberant response can contribute to liver disease. Chronic inflammation and persistent wound healing reactions in large and small bile ducts often lead to liver cancer. General concepts of wound healing as they apply to the biliary tract, importance of cellular processes dependent on IL-6/gp130/STAT3 signaling pathways, unanswered questions, and future directions are discussed.

Simultaneous bone marrow and intestine transplantation promotes marrow-derived hematopoietic stem cell engraftment and chimerism

Organ allografts have been shown to provide a syngeneic microenvironment for organ-based donor hematopoietic stem cells to maintain long-lasting chimerism after transplantation. We hypothesized that organ allografts would also support engraftment and hematopoiesis of adjunctively infused donor marrow stem cells, syngeneic to organ grafts, in nonmyeloablated recipients. In BN-to-LEW and GFP-to-ACI rat combinations, donor bone marrow (BM) infusion together with small intestine transplantation (SITx) under short-course tacrolimus immunosuppression resulted in persistent macrochimerism (more than 5%) for 150 days. In contrast, after BM infusion or SITx alone, chimerism was temporary and disappeared by day 100. Y-chromosome polymerase chain reaction (PCR) in sex-mismatched male BM plus female intestine or female BM plus male intestine transplantation into female recipients suggested that persistent macrochimerism was derived from infused BM. BM infusion together with lymphoid-depleted intestine grafts also supported macrochimerism development; however, third-party intestine grafts did not. After GFP-positive BM plus wild-type (WT) SITx into ACI, large numbers of GFP-positive leukocytes were found in WT intestine grafts. Isolated cells from WT intestine grafts developed GFP-positive CFU-Cs and propagated multilineage GFP-positive leukocytes when adoptively transferred into lethally irradiated WT recipients. These findings suggest that intestine allograft supports simultaneously infused donor (syngeneic to organ grafts) marrow stem cell engraftment, differentiation, and persistence of chimerism.

An inhibitor of cyclin-dependent kinase, stress-induced p21Waf-1/Cip-1, mediates hepatocyte mito-inhibition during the evolution of cirrhosis

During the evolution of cirrhosis, there is a relative decrease in volume percentage of hepatocytes and a relative increase in biliary epithelial cells and myofibroblasts. This is recognized histopathologically as a ductular reaction and leads to gradual distortion of the normal hepatic architecture. The final or decompensated stage of cirrhosis is characterized by a further decline in hepatocyte proliferation and loss of functional liver mass that manifests clinically as ascites, encephalopathy, and other signs of liver failure. In this report, we tested the hypothesis that p21-mediated hepatocyte mito-inhibition accelerates the evolution of cirrhosis using an established mouse model of decompensated biliary cirrhosis, p21-deficient mice, and liver tissue from humans awaiting liver replacement. Despite the same insult of long-term (12-week) bile duct ligation, mice prone to decompensation showed significantly more oxidative stress and hepatocyte nuclear p21 expression, which resulted in less hepatocyte proliferation, an exaggerated ductular reaction, and more advanced disease compared with compensation-prone controls. Mice deficient in p21 were better able than wild-type controls to compensate for long-term bile duct ligation because of significantly greater hepatocyte proliferation, which led to a larger liver mass and less architectural distortion. Mito-inhibitory hepatocyte nuclear p21 expression in humans awaiting liver replacement directly correlated with pathological disease stage and model of end-stage liver disease scoring. In conclusion, stress-induced upregulation of hepatocyte p21 inhibits hepatocyte proliferation during the evolution of cirrhosis. These findings have implications for understanding the evolution of cirrhosis and associated carcinogenesis. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html).