Effects of preoperative chemotherapy on metastatic lymph nodes in esophageal squamous cell carcinoma

Involved-field radiotherapy for esophageal squamous cell carcinoma: theory and practice

Esophageal carcinoma (EC) is characterized by a high rate of lymph node metastasis and its spread pattern is not always predictable. Chemoradiotherapy has an important role in the treatment of EC in both the inoperable and the pre-operative settings. However, regarding the target volume for radiation, different clinical practices exist. Theoretically, in addition to the clinical target volume administered to the gross lesion, it might seem logical to deliver a certain dose to the uninvolved regional lymph node area at risk for microscopic disease. However, in practice, it is difficult because of the intolerance of normal tissue to radiotherapy (RT), particularly if all regions containing the cervical, mediastinal, and upper abdominal nodes are covered. To date, the use of elective nodal irradiation (ENI) is still controversial in the field of radiotherapy. Some investigators use involved-field radiotherapy (IFRT) in order to reduce treatment-related toxicities. It is thought that micrometastases can be controlled, to some extent, by chemotherapy and the abscopal effects of radiation. It is the presence of overtly involved lymph nodes rather than the micrometastatic nodes negatively affects survival in patients with EC. In another hand, lymph nodes stationed near primary tumors also receive considerable incidental irradiation doses that may contribute to the elimination of subclinical lesions. These data indicate that an irradiation volume covering only the gross tumor is appropriate. When using ENI or IFRT, very few patients experience solitary regional node failure and out-of-field lymph node failure is not common. Primary tumor recurrence and distant metastases, rather than regional lymph node failure, affect the overall survival in patients with EC. The available evidence indicates that the use of ENI seems to prevent or delay regional nodal relapse rather than improve survival. In a word, these data suggest that IFRT is feasible in EC patients.

Management of the hepatic lymph nodes during resection of liver metastases from colorectal cancer: a systematic review

BACKGROUND

Hepatic lymph node involvement is generally considered a contraindication for liver resection performed for colorectal liver metastases. However, some advocate hepatic lymphadenectomy in the presence of macroscopic involvement and others routine lymphadenectomy. The aim of this review is to assess the role of lymphadenectomy in resection of liver metastases from colorectal cancer.

METHODS

Medline, Embase and Central databases were searched using a formal search strategy. Trials with survival data with a minimum follow-up of 1 year were considered for inclusion. Meta-analysis was performed using Revman.

RESULTS

A total of 4230 references were identified. Ten reports of nine studies including 926 patients qualified for the review. The prevalence of nodal metastases after routine lymphadenectomy was 16.3%. The overall 3-year and 5-year survival rates in node-positive patients were 9/151 (11.3%) and 2/137 (1.5%), respectively, compared to 3-year and 5-year survival rates of 424/787 (53.9%) and 246/767 (32.1%) in node-negative patients. The odds ratios for 3-year and 5-year survivals in node positive disease compared to node-negative disease were 0.12 (95% CI 0.06 to 0.24) and 0.08 (95% CI 0.03 to 0.22). There was no randomized controlled trial which assessed the survival benefit of routine or "selective" lymphadenectomy.

CONCLUSION

Currently, there is no evidence of survival benefit for routine or selective lymphadenectomy. Survival rates are low in patients with positive lymph nodes draining the liver irrespective of whether they are detected by routine lymphadenectomy or by macroscopic involvement. Further trials in this patient group are required.

Surgical resection versus non-surgical treatment for hepatic node positive patients with colorectal liver metastases

BACKGROUND

Involvement of hepatic lymph node in patients with colorectal liver metastases is associated with poor prognosis.

OBJECTIVES

To determine the benefits and harms of curative liver resection with lymphadenectomy versus other treatments for colorectal liver metastases with hepatic node involvement.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and LILACS until September 2009 for identifying the randomised trials.

SELECTION CRITERIA

We considered only randomised clinical trials (irrespective of language, blinding, or publication status) comparing liver resection (alone or in combination with radiofrequency ablation or cryoablation) versus other treatments (neo-adjuvant chemotherapy, chemotherapy, or radiofrequency ablation) in patients with colorectal liver metastases with hepatic node involvement.

DATA COLLECTION AND ANALYSIS

Two authors independently identified trials for inclusion.

MAIN RESULTS

We were unable to identify any randomised clinical trial fulfilling the inclusion criteria of this review. We were also unable to identify any quasi-randomised or cohort studies, which could meaningfully answer this important issue.

AUTHORS' CONCLUSIONS

There is no evidence in the literature to assess the role of surgery versus other treatments for patients with colorectal liver metastases with hepatic node involvement. High quality randomised clinical trials are feasible and are necessary to determine the optimal management of patients with colorectal liver metastases with hepatic node involvement.

Molecular signature linked to acquired resistance to cisplatin in esophageal cancer cells

To clarify the molecular basis of acquired cisplatin (CDDP) resistance in esophageal squamous cell carcinoma (ESCC), we used cDNA microarray technology. A CDDP-resistant cell line (YES-2/CDDP), which shows a 7.5-fold increase in resistance to CDDP and a 3-fold decrease in CDDP accumulation compared with the parental YES-2 ESCC cell line, was generated from YES-2 by exposure to increased concentrations of CDDP. By cDNA microarray analysis, we identified 44 genes with significantly different expression levels between YES-2/CDDP and YES-2 cells. Interestingly, 15 of these 44 genes encoded ribosome-related proteins, almost all of which were underexpressed in YES-2/CDDP cells. Our present data suggest that many ribosome-related genes may be involved in the acquired resistance to CDDP in ESCC and that such information may allow us to better understand the mechanism of CDDP resistance.

Response to preoperative chemotherapy affects prognosis in esophageal cancer

The effect of preoperative chemotherapy on prognosis is still controversial. We have investigated the relationship between responses to preoperative chemotherapy and prognosis after curative operations in patients with esophageal squamous cell carcinoma. Thirty-nine patients received preoperative chemotherapy with continuous infusion of 500 mg/m2 of 5-fluorouracil (5-FU) and intravenous injection of 20 mg/m2 of leucovorin every 12 hours for 5 days. On the 5th day alone, 70 mg/m2 of cisplatin was also infused. The effect was evaluated approximately 14 days after the end of one course of chemotherapy. The rates of responders and non-responders were 64.1% and 35.9%, respectively. After an interval of 21-28 days, transthoracic esophagectomy was performed. Significant histological effect by chemotherapy was found in responders compared to non-responders (P < 0.05). Responders had a significantly better prognosis than non-responders by Log-rank test (P < 0.01). This suggests that preoperative chemotherapy may contribute to better prognosis when the tumor is sensitive to chemotherapy.