Randomized Phase II Study to Comparing Docetaxel/Nedaplatin versus Docetaxel for 5-Fluorouracil/Cisplatin Resistant Esophageal Squamous Cell Carcinoma

Combination of high anti-SKI and low anti-TMED5 antibody levels is preferable prognostic factor in esophageal carcinoma

Given that esophageal cancer is highly malignant, the discovery of novel prognostic markers is eagerly awaited. We performed serological identification of antigens by recombinant cDNA expression cloning (SEREX) and identified SKI proto-oncogene protein and transmembrane p24 trafficking protein 5 (TMED5) as antigens recognized by serum IgG antibodies in patients with esophageal carcinoma. SKI and TMED5 proteins were expressed in Escherichia coli, purified by affinity chromatography, and used as antigens. The serum anti-SKI antibody (s-SKI-Ab) and anti-TMED5 antibody (s-TMED5-Ab) levels were significantly higher in 192 patients with esophageal carcinoma than in 96 healthy donors. The presence of s-SKI-Abs and s-TMED5-Abs in the patients' sera was confirmed by western blotting. Immunohistochemical staining showed that the TMED5 protein was highly expressed in the cytoplasm and nuclear compartments of the esophageal squamous cell carcinoma tissues, whereas the SKI protein was localized predominantly in the nuclei. Regarding the overall survival in 91 patients who underwent radical surgery, the s-SKI-Ab-positive and s-TMED5-Ab-negative statuses were significantly associated with a favorable prognosis. Additionally, the combination of s-SKI-Ab-positive and s-TMED5-Ab-negative cases showed an even clearer difference in overall survival as compared with that of s-SKI-Ab-negative and s-TMED5-Ab-positive cases. The s-SKI-Ab and s-TMED5-Ab biomarkers are useful for diagnosing esophageal carcinoma and distinguishing between favorable and poor prognoses.

Preoperative Low Serum Calcium Levels Predict Poor Prognosis for Patients with Esophageal Cancer

Purpose: Hypercalcemia has been reported as a poor prognostic factor in malignant tumors. However, no report has shown the clinical impact of serum calcium levels on patients with esophageal cancer. We evaluated the prognostic impact of preoperative serum calcium levels on patients with esophageal cancer.

Methods: We evaluated 240 patients (197 men, 43 women; mean age, 66 years; age range, 34–85 years) with esophageal cancer who underwent radical surgery between September 2008 and December 2017. After assigning the patients to two groups (high calcium group, 8.8 mg/dL or more and low calcium group, 8.7 mg/dL or less), we compared the groups’ overall survival and the clinicopathological features. The clinicopathological and prognostic significance of preoperative serum calcium levels were evaluated in a univariate and multivariate analysis.

Results: The patients with deep tumors showed low serum calcium levels significantly more frequently (P <0.05). The low calcium group showed a significantly worse prognosis than the high calcium group (P <0.05). However, low serum calcium level was not an independent poor prognostic factor.

Conclusions: Preoperative low serum calcium levels were associated with advanced tumors. Low serum calcium might be associated with esophageal cancer progression.