Prognostic risk factors of early esophageal adenocarcinomas.

OBJECTIVE: To define prognostic risk factors in patients with early adenocarcinomas of the esophagus (eACEs) who were treated by esophagectomy. BACKGROUND: Although endoscopic resection (ER) is more accepted for eACEs limited to the mucosa, the reported prevalence of lymph node metastases once the tumor infiltrates the submucosa seems to necessitate surgery in these cases. METHODS: We analyzed the results of 168 patients who had an esophageal resection because of an eACE. On the basis of specimen histologies and clinical follow-up (median, 64 months), we investigated the influence of lymph node metastases (N+), tumor infiltration depth, tumor differentiation (G1-3), and lymphatic or venous infiltration (L+ or V+) on overall and tumor-specific survival and recurrence rates. RESULTS: The 5-year survival rate was 79%. Lymph node infiltration was the only prognostic factor for the overall survival [hazard ratio (HR), 2.856; 1.314-6.207; P = 0.008], tumor-specific survival (HR, 8.336; 2.734-25.418; P < 0.001), and tumor recurrence (HR, 8.031; 3.041-21.206; P < 0.001) that was consistently present in all multivariate hazard Cox regression analyses. A total of 47% of the patients who had an N+ status developed tumor recurrences compared with 5.2% of those who had no lymph node involvement (P = <0.001). We found a significant correlation between N+ status and increasing depth of tumor infiltration (P = 0.004), lymphatic vessel infiltration (P = 0.002), tumor differentiation (G1 + G2 vs G3; P = 0.014) and vascular infiltration (P = 0.01). CONCLUSIONS: Lymph node status is the only independent risk factor for survival and recurrence rates. Tumor infiltration depth correlates with the rate of the lymph node metastases, but a clear watershed between deep mucosal and submucosal infiltration does not exist. As a consequence, careful staging procedures, including diagnostic ER, are mandatory to determine which patients can be treated by ER and which require an esophagectomy.

c-Fos is required for excision repair of UV-light induced DNA lesions by triggering the re-synthesis of XPF.

Cells deficient in c-Fos are hypersensitive to ultraviolet (UV-C) light. Here we demonstrate that mouse embryonic fibroblasts lacking c-Fos (fos-/-) are defective in the repair of UV-C induced DNA lesions. They show a decreased rate of sealing of repair-mediated DNA strand breaks and are unable to remove cyclobutane pyrimidine dimers from DNA. A search for genes responsible for the DNA repair defect revealed that upon UV-C treatment the level of xpf and xpg mRNA declined but, in contrast to the wild type (wt), did not recover in fos-/- cells. The observed decline in xpf and xpg mRNA is due to impaired re-synthesis, as shown by experiments using actinomycin D. Block of xpf transcription resulted in a lack of XPF protein after irradiation of fos-/- cells, whereas the XPF level normalized quickly in the wt. Although the xpg mRNA level was reduced, the amount of XPG protein was not altered in c-Fos-deficient cells after UV-C, due to higher stability of the XPG protein. The data suggest a new role for c-Fos in cells exposed to genotoxic stress. Being part of the transcription factor AP-1, c-Fos stimulates NER via the upregulation of xpf and thus plays a central role in the recovery of cells from UV light induced DNA damage.

Fen1 is induced p53 dependently and involved in the recovery from UV-light-induced replication inhibition.

Mouse embryonic fibroblasts (MEFs) that lack p53 are hypersensitive to the cytotoxic and genotoxic effect of ultraviolet (UV-C) light. They also display a defect in the recovery from UV-C-induced DNA replication inhibition. An enzyme involved in processing stalled DNA replication forks is flap endonuclease 1 (Fen1). Gene expression profiling of UV-C-irradiated MEFs revealed fen1 to be upregulated, which was confirmed by RT-PCR and Western blot experiments. Increased Fen1 levels upon UV-C exposure are due to transcriptional activation, as revealed by inhibitor studies. Fen1 induction was dose- and time-dependent; it occurred on protein level already 3 h after irradiation. Induction of Fen1 by UV-C requires p53 since it was observed in p53 wild-type (wt) but not in p53 null (p53-/-) fibroblasts. Fen1 upregulation paralleled the increase in p53 protein level in replicating wt cells, whereas in nonreplicating cells both Fen1 and p53 were not induced by UV-C. The mouse fen1 promoter was cloned and shown to harbor a p53 consensus sequence to which p53 binds. In cotransfection experiments, p53 stimulated the expression of a fen1 promoter-reporter construct. Transgenic expression of Fen1 in p53 null cells attenuated UV-C light-induced DNA replication inhibition, supporting the hypothesis that Fen1 induction is involved in the recovery of cells from DNA damage.

pT2 Adenocarcinoma of the esophagus: early or advanced cancer?

BACKGROUND: There is an increasing trend to include patients with esophageal carcinoma invading the muscularis propria (pT2) in neoadjuvant therapy regimens. But it is unclear which patients have prognostic benefit from this strategy. The aim of this study was to assess the prognosis and prognostic factors in patients with pT2 esophageal adenocarcinoma to further optimize treatment strategies. METHODS: Included were patients with pT2 esophageal adenocarcinoma treated operatively at three centers specializing in upper gastrointestinal surgery. There were 159 patients (139 male) without induction therapy; median age was 64.5 years. Survival was analyzed by univariate and multivariate analysis. RESULTS: In 37% of patients (n = 59), no lymph node involvement (pN0) was detected. Overall 5-year survival rate for all patients was 37%; for pN0 patients it was 62%, and for patients with lymph node metastases (pN+) it was 24%. Median number of examined lymph nodes was 26. Extracapsular lymph node involvement (ELNI) was evident in 55 of 100 pN+ patients with a 5-year survival rate of 14%. Patients without ELNI had a 5-year survival rate of 36% (p = 0.041). Results were comparable in all participating hospitals. Thirty-day and 90-day mortality rates of the entire collective were 2.6% and 3.8%, respectively. Multivariate analysis of prognosis revealed the lymph node ratio (p < 0.001) and the pN-ELNI category (p = 0.005) as significant parameters (pN0 hazard ratio 1 [reference]; pN+ without ELNI hazard ratio 2.2, 95% confidence interval: 1.2 to 3.8); pN+ with ELNI hazard ratio 2.5, 95% confidence interval: 1.5 to 4.5). CONCLUSIONS: The prognosis of patients with esophageal adenocarcinoma invading the muscularis propria without lymph node metastasis is very good. However, in this study, about 30% had extracapsular lymph node involvement, which reflects particularly aggressive biological tumor behavior.