应用Cox模型分析影响胆管癌切除术后的预后因素

目的：探讨影响胆管癌切除术后的预后因素。方法：对1980－1995年86例胆管癌切除术后患者进行研究。选择15个可能对胆管癌切除术后预后产生影响的非重复性特征临床因素，通过Cox比例风险模型对胆管癌切除术后患者预后进行多因素分析。结果；全组1年生存率为72．6％，3年生存率为32．4％，5年生存为18．7％。单因素分析得出肿瘤的组织学类型，淋巴结转移，胰腺浸润，十二指肠浸润，神经浸润，周围血管浸润，切缘癌残留和浸润深度对预后有影响（P＜0．05）。Cox模型多因素分析结果表明，胰腺浸润，神经浸润和淋巴结转移是影响预后的主要因素。结论：胰腺浸润，神经浸润和淋巴结转移状况是胆管癌切除术后影响预后的最重要因素。     

Tumors of the ampulla of vater: histopathologic classification and predictors of survival

BACKGROUND: The histology and clinical behavior of ampullary tumors vary substantially. We speculated that this might reflect the presence of two kinds of ampullary adenocarcinoma: pancreaticobiliary and intestinal. STUDY DESIGN: We analyzed patient demographics, presentation, survival (mean followup 44 months), and tumor histology for 157 consecutive ampullary tumors resected from 1989 to 2006. Histologic features were reviewed by a pathologist blinded to clinical outcomes. Survival was compared using Kaplan-Meier/Cox proportional hazards analysis. RESULTS: There were 33 benign (32 adenomas and 1 paraganglioma) and 124 malignant (118 adenocarcinomas and 6 neuroendocrine) tumors. One hundred fifteen (73%) patients underwent a Whipple procedure, 32 (20%) a local resection, and 10 (7%) a palliative operation. For adenocarcinomas, survival in univariate models was affected by jaundice, histologic grade, lymphovascular, or perineural invasion, T stage, nodal metastasis, and pancreaticobiliary subtype (p < 0.05). Size of tumor did not predict survival, nor did cribriform/papillary features, dirty necrosis, apical mucin, or nuclear atypia. In multivariate models, lymphovascular invasion, perineural invasion, stage, and pancreaticobiliary subtype predicted survival (p < 0.05). Patients with pancreaticobiliary ampullary adenocarcinomas presented with jaundice more often than those with the intestinal kind (p = 0.01) and had worse survival. CONCLUSIONS: In addition to other factors, tumor type (intestinal versus pancreaticobiliary) had a major effect on survival in patients with ampullary adenocarcinoma. The current concept of ampullary adenocarcinoma as a unique entity, distinct from duodenal and pancreatic adenocarcinoma, might be wrong. Intestinal ampullary adenocarcinomas behaved like their duodenal counterparts, but pancreaticobiliary ones were more aggressive and behaved like pancreatic adenocarcinomas.     

影响胆管癌患者生存预后因素的研究

目的 探讨影响胆管癌切除术后的预后因素。方法 对1980-1995年86例胆管癌切除术后患各进行研究。选择15个可能对胆管癌切除术后预门产生影响的非重要性特证性临床因素,通过Cox比例风险模型对胆管癌切除术后患者预后进行多因素分析。结果 全组1年生存率为72.6％,3年生存率为32.4％,5年生存率为18.7％。单因素分析得出肿瘤的组织学类型、淋巴结转移、胰腺浸润、十二指肠浸润、神经浸润、周围血管浸润、切缘癌残留和浸润浙度对预后有影响（P<0.05）。Cox模型多因素分析结果表明胰腺浸润、神经浸润和淋巴结转移是影响预后的主要因素。结论 胰腺浸润、神经浸润和淋巴结转移状况足胆管癌切除术后影响预后的最重要因素。     

Guidelines for the management of biliary tract and ampullary carcinomas: surgical treatment

The only curative treatment in biliary tract cancer is surgical treatment. Therefore, the suitability of curative resection should be investigated in the first place. In the presence of metastasis to the liver, lung, peritoneum, or distant lymph nodes, curative resection is not suitable. No definite consensus has been reached on local extension factors and curability. Measures of hepatic functional reserve in the jaundiced liver include future liver remnant volume and the indocyanine green (ICG) clearance test. Preoperative portal vein embolization may be considered in patients in whom right hepatectomy or more, or hepatectomy with a resection rate exceeding 50%–60% is planned. Postoperative complications and surgery-related mortality may be reduced with the use of portal vein embolization. Although hepatectomy and/or pancreaticoduodenectomy are preferable for the curative resection of bile duct cancer, extrahepatic bile duct resection alone is also considered in patients for whom it is judged that curative resection would be achieved after a strict diagnosis of its local extension. Also, combined caudate lobe resection is recommended for hilar cholangiocarcinoma. Because the prognosis of patients treated with combined portal vein resection is significantly better than that of unresected patients, combined portal vein resection may be carried out. Prognostic factors after resection for bile duct cancer include positive surgical margins, especially in the ductal stump; lymph node metastasis; perineural invasion; and combined vascular resection due to portal vein and/or hepatic artery invasion. For patients with suspected gallbladder cancer, laparoscopic cholecystectomy is not recommended, and open cholecystectomy should be performed as a rule. When gallbladder cancer invading the subserosal layer or deeper has been detected after simple cholecystectomy, additional resection should be considered. Prognostic factors after resection for gallbladder cancer include the depth of mural invasion; lymph node metastasis; extramural extension, especially into the hepatoduodenal ligament; perineural invasion; and the degree of curability. Pancreaticoduodenectomy is indicated for ampullary carcinoma, and limited operation is also indicated for carcinoma in adenoma. The prognostic factors after resection for ampullary carcinoma include lymph node metastasis, pancreatic invasion, and perineural invasion.     

Aggressive surgical approach for stage IV gallbladder carcinoma based on Japanese Society of Biliary Surgery classification

BACKGROUND/PURPOSE: The role of aggressive surgery for stage IV gallbladder carcinoma remains controversial. Survival and prognostic factors were analyzed in patients with stage IV disease, based on the Japanese Society of Biliary Surgery (JSBS) classification, to identify the group of patients who could benefit from radical surgery. METHODS: A retrospective analysis was done of 79 patients with JSBS stage IV gallbladder carcinoma who had undergone surgical resection with curative intent at our institution. The standard procedures were anatomical S4a + S5 subsegmentectomy (n = 29) with extrahepatic bile duct resection and extended lymphadectomy, but when right Glisson's sheath and/or the hepatic hilum were involved, right extended hepatectomy (n = 34) or right trisegmentectomy (n = 3) was selected. To achieve a tumor-free margin combined pancreaticoduodenectomy was performed in 12 patients, and major vascular resection in 17 patients. RESULTS: In the patients with stage IV gallbladder carcinoma, the curative resection rate was 65.8% and the hospital mortality rate was 11.4%. The postoperative 5-year survival rate following curative resection was 13.7%. Univariate analysis indicated that curability, hepatoduodenal ligament invasion, nodal involvement, and vascular resection were significant prognostic factors. Neither hepatic invasion nor liver metastasis was a significant factor. CONCLUSIONS: Aggressive surgical resection should be considered even in stage IV patients when hepatoduodenal ligament invasion and nodal involvement are absent or limited. Acceptable survival may be expected among such patients only when curative resection is achieved.     

Intestinal-type and Pancreatobiliary-type Adenocarcinomas: How Does Ampullary Carcinoma Differ from Other Periampullary Malignancies?

Background

Ampullary carcinomas typically have either intestinal or pancreatobiliary type of differentiation, histopathologically resembling carcinomas of its adjacent tissues (duodenum, bile duct, or pancreas). We evaluated whether the histologic type itself is more important for long-term survival than the fact that the tumor originated in the ampulla.

Methods

Microscopic slides from 207 consecutive pancreatoduodenectomies were reviewed (72 pancreatic, 46 biliary, 61 ampullary, and 28 duodenal adenocarcinomas; 76 intestinal type, 131 pancreatobiliary type). Tumor size, nodal involvement, margin involvement, degree of differentiation, vascular involvement, and perineural growth, as well as overall survival, were compared between different origins of the same histologic type.

Results

Intestinal-type ampullary adenocarcinomas had similar frequency of poor histopathologic factors compared to duodenal adenocarcinomas, and pancreatobiliary-type ampullary adenocarcinomas had similar frequency of poor histopathologic factors compared to pancreatobiliary-type biliary and pancreatic adenocarcinomas. Adjusting for tumor size and nodal involvement, there was no difference in long-term survival between patients with intestinal-type ampullary, duodenal, or biliary and pancreatic tumors (p = 0.79), and there was no difference in long-term survival between patients with pancreatobiliary-type ampullary, biliary, or pancreatic tumors (p = 0.41).

Conclusions

Long-term survival for patients with ampullary carcinomas equals pancreatic, biliary, and duodenal carcinomas when the same histologic type is compared. It can be questioned whether ampullary carcinomas should be regarded as a separate entity in classification of solid tumors. Clinical trials on adjuvant treatments for periampullary carcinomas should stratify by pancreatobiliary type versus intestinal type of histologic differentiation.     

Validation of the eighth edition of the American Joint Committee on Cancer staging system for ampulla of Vater cancer

Background

The American Joint Committee on Cancer recently proposed the eighth edition of cancer staging system. Validation studies are required to evaluate the prognostic stratification of ampulla of Vater cancer patients.

Predictors for Patterns of Failure after Pancreaticoduodenectomy in Ampullary Cancer

Background Ampullary cancer has the best prognosis in periampullary malignancy but unpredicted early recurrence after resection is frequent. The current study tried to find the predictors for recurrence to be used as determinative for postoperative adjuvant therapy. Methods Information was collected from patients who underwent pancreaticoduodenectomy with regional lymphadenectomy for ampullary cancer in high-volume hospitals between January 1989 and April 2005. Recurrence patterns and survival rates were calculated and predictors were identified. Results A total of 135 eligible patients were included. The 30-day operative mortality was 3%. Median followup for relapse-free patients was 52 months. Disease recurred in 57 (42%) patients, including 31 liver metastases, 26 locoregional recurrences, 9 peritoneal carcinomatoses, 7 bone metastases, and 6 other sites. Pancreatic invasion (P = 0.04) and tumor size (P = 0.05) were the predictors for locoregional recurrence, while lymph node metastasis was the sole predictor for liver metastasis (P = 0.01). The 5-year disease-specific survival rate was 45.7%; 77.7% for stage I, 28.5% for stage II, and 16.5% for stage III; and 63.7% for node-negative versus 19.1% for node-positive patients. Pancreatic invasion and lymph node involvement were both predictors for survival of patients with ampullary cancer. Conclusion Pancreaticoduodenectomy with regional lymphadenectomy is adequate for early-stage ampullary cancer but a dismal outcome can be predicted in patients with lymph node metastasis and pancreatic invasion. Lymph node metastasis and pancreatic invasion can be used to guide individualized, risk-oriented adjuvant therapy.     

Jaundice at Presentation Heralds Advanced Disease and Poor Prognosis in Patients with Ampullary Carcinoma

Jaundice is a common manifestation of ampullary carcinoma. The aim of this study was to evaluate the correlation between jaundice at initial presentation and the degree of tumor spread and to determine the prognostic significance of jaundice in patients with ampullary carcinoma. Fifty-nine patients who had undergone curative resection for ampullary carcinoma were analyzed retrospectively. Jaundice was defined as a total bilirubin serum concentration of ≥ 3 mg/dl. The median follow-up time was 106 months. Jaundice was noted at the time of initial presentation in 43 (73%) patients. Jaundice at presentation correlated with lymph node metastasis (p < 0.0001), lymphatic vessel invasion (p < 0.0001), invasion into the pancreas (p = 0.0007), and vascular invasion (p = 0.0487). Pancreatic invasion was absent in patients without jaundice. Superior mesenteric nodal involvement was more frequent in patients with jaundice (15/43) than in those without (0/16) (p = 0.0062). The survival of patients with jaundice (median survival 48 months; cumulative 10-year survival rate 39%) was worse than for patients without jaundice (median survival time not available; cumulative 10-year survival rate 86%) (p = 0.0014). In conclusion, jaundice at presentation predicts advanced-stage ampullary carcinoma and a poor prognosis. Pancreatic invasion and superior mesenteric nodal involvement were not observed in nonjaundiced patients.     

Treatment of patients with gastric cancer and duodenal invasion

We retrospectively examined clinicopathologic features of gastric cancer with duodenal invasion to clarify the effect of surgical treatment that include pancreaticoduodenectomy (PD). Among 2504 patients with gastric cancer, 69 (2.8%) who had gastric cancer and duodenal invasion resected by surgical treatment were investigated. The mode of the duodenal invasion was grouped into three categories: mucosal type, submucosal type, and nodal type. Mucosal type is invasion of the duodenal mucosal layer, submucosal type is invasion of the submucosal layer or deeper, and nodal type is invasion from nodal metastatic lesions around the pancreatic head. The 5-year survival rates of curative PD and curative gastrectomy were 37.3% and 33.8%, respectively. Despite the incidence of adjacent tissue infiltration and significantly higher duodenal invasion average length in cases with PD than in cases with gastrectomy, there was no significant difference in the survival curves. However, the prognoses of the cases with nodal-type invasion were significantly poorer, and all these patients died within 2 years, regardless of whether curative PD had been performed. Curative PD improves the prognosis of cases with long duodenal invasion or pancreas infiltration except for nodal-type duodenal invasion.     

Surgical treatment of primary carcinoma of the gallbladder based on the histologic analysis of 48 surgical specimens.

During the past 5 years, extended cholecystectomy and/or more radical procedures, including pancreatoduodenectomy and extended hepatic lobectomy, were performed on 48 patients with carcinoma of the gallbladder in an attempt to cure the disease. It was retrospectively proven from microscopic analysis of the surgical specimens taken from the 48 patients that 28 patients had received curative resections. The 28 consisted of all 4 patients with stage I carcinoma, all 9 with stage II, 6 of 8 with stage III, and 9 of 27 with stage IV. We reached the following conclusions: (1) extended cholecystectomy with resection of the bile duct in the hepatoduodenal ligament is the optimum procedure for patients with stage I and stage II carcinomas, and (2) for patients with stage III carcinoma, more radical procedures, including pancreatoduodenectomy and/or wider resection of the liver, might result in curative resection of the disease. For some patients with stage IV tumors, such as duodenal invasion or direct invasion of the liver, curative resection may be achieved by pancreatoduodenectomy or extended hepatic lobectomy.     

Periampullary adenocarcinoma: analysis of 5-year survivors.

OBJECTIVE: This single-institution experience retrospectively reviews the outcomes in a group of patients treated 5 or more years ago by pancreaticoduodenectomy for periampullary adenocarcinoma. SUMMARY BACKGROUND DATA: Controversy exists regarding the benefit of resection for periampullary adenocarcinoma, particularly for pancreatic tumors. Many series report only Kaplan-Meier actuarial 5-year survival rates. There are believed to be discrepancies between the actuarial 5-year survival data and the actual 5-year survival rates. METHODS: From April 1970 through May 1992, 242 patients underwent pancreaticoduodenal resection for periampullary adenocarcinoma at The Johns Hopkins Hospital. Follow-up was complete through May 1997. All pathology specimens were reviewed and categorized. Actual 5-year survival rates were calculated. The demographic, intraoperative, pathologic, and postoperative features of patients surviving > or =5 years were compared with those of patients who survived <5 years. RESULTS: Of the 242 patients with resected periampullary adenocarcinoma, 149 (62%) were pancreatic primaries, 46 (19%) arose in the ampulla, 30 (12%) were distal bile duct cancers, and 17 (7%) were duodenal cancers. There was a 5.3% operative mortality rate during the 22 years of the review, with a 2% operative mortality rate in the last 100 patients. There were 58 5-year survivors, 28 7-year survivors, and 7 10-year survivors. The tumor-specific 5-year actual survival rates were pancreatic 15%, ampullary 39%, distal bile duct 27%, and duodenal 59%. When compared with patients who did not survive 5 years, the 5-year survivors had a significantly higher percentage of well-differentiated tumors (14% vs. 4%; p = 0.02) and higher incidences of negative resection margins (98% vs. 73%, p < 0.0001) and negative nodal status (62% vs. 31%, p < 0.0001). The tumor-specific 10-year actuarial survival rates were pancreatic 5%, ampullary 25%, distal bile duct 21%, and duodenal 59%. CONCLUSIONS: Among patients with periampullary adenocarcinoma treated by pancreaticoduodenectomy, those with duodenal adenocarcinoma are most likely to survive long term. Five-year survival is less likely for patients with ampullary, distal bile duct, and pancreatic primaries, in declining order. Resection margin status, resected lymph node status, and degree of tumor differentiation also significantly influence long-term outcome. Particularly for patients with pancreatic adenocarcinoma, 5-year survival is not equated with cure, because many patients die of recurrent disease >5 years after resection.     

Clinical significance of lymph node micrometastasis in gallbladder carcinoma

BACKGROUND: This retrospective study was intended to define the clinical significance of lymph node micrometastasis in gallbladder carcinoma. METHODS: A total of 1136 regional lymph nodes taken from 63 consecutive patients undergoing radical resection were examined histologically. Micrometastasis was defined as a metastasis missed on routine histologic examination with hematoxylin-and-eosin but detected by immunohistochemical examination with an antibody against cytokeratins 8 and 18. RESULTS: None of 9 patients (0%) with pT1 disease and 19 of 54 patients (35%) with pT2-4 disease had nodal micrometastases. Univariate analysis identified nodal micrometastasis, type of radical resection, M classification, pT classification, perineural invasion, pTNM stage, timing of radical resection, lymphatic vessel invasion, and pN classification as significant variables. Multivariate analysis revealed that nodal micrometastasis (P =.0003) and type of radical resection (P=.0044) were independent prognostic factors. Nodal micrometastasis affected survival adversely, despite the absence (P=.0002) or presence (P <.0001) of overt nodal metastasis. Nodal micrometastasis correlated significantly with invasive characteristics: lymphatic vessel invasion, perineural invasion, and distant metastasis. CONCLUSIONS: Lymph node micrometastasis is the strongest independent predictor of worse survival regardless of the overt nodal status and may indicate aggressive tumor biology among patients undergoing curative resection for gallbladder carcinoma.     

Treatment for pancreatic endocrine tumors with or without multiple endocrine neoplasia type 1

Recent strategies for the treatment of pancreatic endocrine tumors are described. Most cases are metastatic, and liver metastasis is the most significant prognostic factor. Thus curative resection before liver metastasis develops based on the localization of the tumors with the SASI test is the standard strategy. Subtotal distal pancreatectomy or pancreas-preserving total duodenectomy is indicated for multiple pancreatic endocrine tumors and multiple duodenal gastrinomas, respectively, for patients with multiple endocrine neoplasia type 1.     

Role of nodal involvement and the periductal soft-tissue margin in middle and distal bile duct cancer.

OBJECTIVE: To determine the pattern of middle (Bm) and distal (Bi) bile duct cancers in an attempt to optimize surgical treatment. SUMMARY BACKGROUND DATA: Lymph node involvement and neural plexus invasion are the prognostic factors most amenable to surgery in Bm and Bi disease. However, a detailed analysis of these factors has not been conducted. METHODS: Fifty patients with Bm and Bi disease (Bm 14 patients, Bi 36 patients) were examined histopathologically. A precise determination was made of lymph node involvement and neural plexus invasion. Important prognostic factors were examined by clinicopathologic study to apply these findings to surgical management. RESULTS: Frequencies of nodal involvement for Bm and Bi disease were 57% and 71%, respectively. The inferior periductal and superior pancreaticoduodenal lymph nodes were most commonly involved. Neural plexus invasion occurred in 20% of patients, particularly involving the plexus in the hepatoduodenal ligament and pancreatic head. Tumor was present at the surgical margin in 50% and 14% of patients with Bm and Bi disease, respectively. Five-year survival rates were 65% in the absence of nodal metastasis and 21% with nodal metastasis. A significant correlation existed between absence of tumor at the surgical margin and survival. A Cox proportional hazard model projected absence of tumor at the surgical margin, followed by nodal involvement, as the strongest prognostic variables. CONCLUSIONS: Absence of tumor at the surgical margin and nodal involvement are important independent prognostic factors in Bm and Bi disease. Skeletonization of the hepatoduodenal ligament, including portal vein resection, is necessary for patients with Bm disease, and a wide nodal dissection is essential in all patients.     

从胰腺癌患者的长期生存看预后因素及治疗模式

Pancreatic cancer has the characteristics of high malignancy, early dissemination within the pancreas,extrapancreatic nerve plexus invasion, lymph node metastasis and vascular invasion. The 5-year survival rate of pancreatic cancer patients was under 5% even for those who had undergone surgical resection. Based on the review of the literatures including 42 pancreatic cancer patients who survived for 5-20 years after the operation, we concluded that curative resection of pancreatic cancer was still a reliable means in achieving long-term survival; factors influencing the results of resection of pancreatic cancer were lymph nodes involvement, poor differentiated tumor, extrapancreatic nerve plexus invasion, tumor size, residual tumor, curative resection and adjuvant chemotherapy; early diagnosis, aggressive surgery for patients with indications of resection, appropriate surgical procedure and postoperative adjuvant chemotherapy are essential factors to ensure a long term survival of patients with pancreatic cancer.     

从胰腺癌患者的长期生存看预后因素及治疗模式

胰腺癌恶性程度高,具有早期胰腺内播散,胰腺外神经丛侵犯,淋巴结转移与血管侵犯的特点.即使外科切除,大部分患者5年生存率仍<5%. 1长期生存的特征     

Longterm favorable results of limited hepatic resections for patients with hepatocellular carcinoma: 20 years of experience

BACKGROUND: Recently, anatomic resection has been, in theory, considered preferable for eradicating portal venous tumor extension and intrahepatic metastasis in hepatocellular carcinoma (HCC). We have reported the effectiveness of limited hepatic resection for cirrhotic patients with HCC. STUDY DESIGN: A retrospective study was carried out in 321 patients who underwent curative hepatic resection (anatomic resection, n=201; limited resection, n=120) as the initial treatment for solitary HCC<5 cm in our institution in the period 1985 to 2004 (median followup period 5.1 years). RESULTS: Anatomic resection did not influence overall and recurrence-free survival rates after hepatic resection. In the liver damage A group (n=215), both 5-year overall and recurrence-free survival rates in the anatomic resection group were considerably better than those in the limited resection group (87% versus 76%, p=0.02, and 63% versus 35%, p<0.01, respectively). In the liver damage B group (n=106), both 5-year overall and recurrence-free survival rates in the anatomic resection group were substantially worse than those in the limited resection group (48% versus 72%, p<0.01, and 28% versus 43%, p=0.01, respectively). The results of multivariate analysis revealed that anatomic resection was a notably poor factor in promoting recurrence-free survival in patients with liver damage B. CONCLUSIONS: Anatomic resection should be recommended for noncirrhotic patients (liver damage A) with HCC. Longterm results of limited hepatic resection proved its validity for cirrhotic patients (liver damage B) with HCC.     

胰头癌与壶腹癌可切除性及临床行为特点差异的比较研究

目的探讨胰头癌与壶腹癌在可切除性、肿瘤局部浸润、血管侵犯、淋巴结转移、远处转移、预后等临床行为特点的差异。方法同期收治的胰头癌42例、壶腹癌26例为本研究对象，以手术发现和病理诊断作为金标准，探讨上述指标两组之间的差异。结果同期收治的壶腹癌26例和胰头癌42例中，壶腹癌切除率84．62％，胰头癌的手术切除率为19．05％，胰头癌发生血管侵犯为83．33％，壶腹癌为11．54％，两组间均存在显著差异（P〈0.01）。在肿瘤局部组织浸润（P=0.13）、淋巴结转移（P=0．15）、远处转移（P=0.54），两组间无差异；两组TNM分期构成亦存在明显差异（P〈0．01）。结论壶腹癌与胰头癌因其原发组织、生长部位不同，其临床行为特点各异，术前应力争明确肿瘤部位以利于制定正确治疗方案。     

切缘宽度对结直肠癌肝转移同期肝切除患者术后生存的影响

目的探讨结直肠癌同期肝切除术合适的肝转移瘤切缘宽度。方法回顾性分析1994年8月至2004年12月行肝肠同期切除的39例同时性结直肠癌肝转移患者的临床资料,将患者根据肝转移瘤切缘宽度小于1cm和大于或等于1cm分为A、B两组,用Kaplan—Meier法进行生存分析,用Log-rank检验比较两组术后的生存期。结果A组患者14例,B组患者25例;两组患者性别、年龄、原发瘤浸润深度、淋巴结转移、肝转移瘤数目和分布及最大直径、手术时间和术中出血量比较．差异均无统计学意义（P〉0．05）。两组患者中位生存期分别为17和37个月（P〈0．01）,5年生存率分别为0和19．8％（P〈0．01）,差异有统计学意义。结论结直肠癌肝转移行同期肝切除术时应力争肝转移瘤切缘宽度大于或等于1cm。