Development and external validation of a nomogram for overall survival after curative resection in serosa-negative, locally advanced gastric cancer

BACKGROUND

Few nomograms can predict overall survival (OS) after curative resection of advanced gastric cancer (AGC), and these nomograms were developed using data from only a few large centers over a long time period. The aim of this study was to develop and externally validate an elaborative nomogram that predicts 5-year OS after curative resection for serosa-negative, locally AGC using a large amount of data from multiple centers in Japan over a short time period (2001-2003).

PATIENTS AND METHODS

Of 39 859 patients who underwent surgery for gastric cancer between 2001 and 2003 at multiple centers in Japan, we retrospectively analyzed 5196 patients with serosa-negative AGC who underwent Resection A according to the 13th Japanese Classification of Gastric Carcinoma. The data of 3085 patients who underwent surgery from 2001 to 2002 were used as a training set for the construction of a nomogram and Web software. The data of 2111 patients who underwent surgery in 2003 were used as an external validation set.

RESULTS

Age at operation, gender, tumor size and location, macroscopic type, histological type, depth of invasion, number of positive and examined lymph nodes, and lymphovascular invasion, but not the extent of lymphadenectomy, were associated with OS. Discrimination of the developed nomogram was superior to that of the TNM classification (concordance indices of 0.68 versus 0.61; P < 0.001). Moreover, calibration was accurate.

CONCLUSIONS

We have developed and externally validated an elaborative nomogram that predicts the 5-year OS of postoperative serosa-negative AGC. This nomogram would be helpful in the assessment of individual risks and in the consideration of additional therapy in clinical practice, and we have created freely available Web software to more easily and quickly predict OS and to draw a survival curve for these purposes.

On-Site Detection as a Countermeasure to Chemical Warfare/Terrorism

On-site monitoring and detection are necessary in the crisis and consequence management of wars and terrorism involving chemical warfare agents (CWAs) such as sarin. The analytical performance required for on-site detection is mainly determined by the fatal vapor concentration and volatility of the CWAs involved. The analytical performance for presently available on-site technologies and commercially available on-site equipment for detecting CWAs interpreted and compared in this review include: classical manual methods, photometric methods, ion mobile spectrometry, vibrational spectrometry, gas chromatography, mass spectrometry, sensors, and other methods. Some of the data evaluated were obtained from our experiments using authentic CWAs. We concluded that (a) no technologies perfectly fulfill all of the on-site detection requirements and (b) adequate on-site detection requires (i) a combination of the monitoring-tape method and ion-mobility spectrometry for point detection and (ii) a combination of the monitoring-tape method, atmospheric pressure chemical ionization mass spectrometry with counterflow introduction, and gas chromatography with a trap and special detectors for continuous monitoring. The basic properties of CWAs, the concept of on-site detection, and the sarin gas attacks in Japan as well as the forensic investigations thereof, are also explicated in this article.

Two Japanese Corynebacterium ulcerans isolates from the same hospital: ribotype, toxigenicity and serum antitoxin titre

Two toxigenic Corynebacterium ulcerans isolates recovered from pharyngeal swabs of two patients from the same hospital in Japan during 2001–2002 were characterized by PFGE and ribotyping. Toxin production in different culture media was examined and serological analysis of patient sera was performed. The two isolates could not be distinguished by PFGE; however, their ribotypes were distinguishable. One of the isolates could represent a novel ribotype. Analysis of toxin production in different culture media demonstrated that the two isolates produced varying amounts of the diphtheria toxin. Serological analysis showed a greater than sevenfold increase in the serum antitoxin titre during the course of infection in one patient.

A unique lantibiotic, thermophilin 1277, containing a disulfide bridge and two thioether bridges

AIMS

To identify the chemical structure of a bacteriocin, thermophilin 1277, produced by Streptococcus thermophilus SBT1277.

METHODS AND RESULTS

Thermophilin 1277 was purified and partial N-terminal sequence analysis revealed 6 unidentified amino acids amongst 31 amino acids residues. A 2.7-kbp region containing the thermophilin 1277 structural gene (tepA) encoding 58 amino acids was cloned and sequenced. Mature thermophilin 1277 (33 amino acids) was preceded by a 25-amino acid putative leader peptide containing a double glycine cleavage motif. Peptide sequence analysis following chemical modification of thermophilin 1277 revealed that the Cys21 and Cys29 residues form a disulfide bridge and that Thr8 or Thr10 forms two 3-methyllanthionines with Cys13 or Cys32 via thioether bridges. Antimicrobial activity was disrupted by ethanethiol or reductive agent treatments, indicating that the internal amino acid modifications are crucial for the activity.

CONCLUSIONS

Thermophilin 1277 from Strep. thermophilus SBT1277 belongs to the class of AII-type lantibiotics that has a disulfide and two thioether bridges.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report of a lantibiotic produced by a GRAS species of Strep. thermophilus; thermophilin 1277 has a unique structure containing both a disulfide bridge and two thioether bridges that are crucial for its activity.

Can immune-enhancing nutrients reduce postoperative complications in patients undergoing esophageal surgery?

Postoperative infection of esophageal neoplasm surgery is the major cause of prolonged postoperative hospitalization, as well as morbidity. The clinical benefits of administering immune-enhancing nutrients (IEN) to critically ill patients and those undergoing elective surgery were clarified. However, the benefits of preoperative administration of IEN for patients with esophageal cancer remain unclear. The present study was designed to clarify the clinical efficacy of administration of IEN prior to esophageal surgery. A total of 123 patients undergoing esophagectomy in single institute were retrospectively investigated. All patients received postoperative enteral nutrition by use of ordinal nutrients. Preoperative IEN were also given to 84 patients (IEN group), while the other 39 received an ordinary diet (control). Postoperative courses and laboratory data were compared between the two groups. The incidences of infectious complications in the IEN and control groups were 18% and 38%, respectively (P < 0.05). Pneumonia developed in 5 (6%) IEN and 7 (18%) control patients (P < 0.05). Postoperative hospitalization was shorter in the IEN group (P < 0.01). Prealbumin levels, retinal binding protein levels and the lymphocyte count were significantly higher in the IEN group on postoperative day 3. These results suggest that preoperative administration of IEN in patients undergoing esophagectomy reduces infectious complications, mainly pneumonia, and shortens postoperative hospitalization.

Celiac lymph nodes: distant or regional for thoracic esophageal carcinoma?

Involvement of celiac nodes is defined as distant metastasis in the TNM classification for thoracic esophageal carcinoma. Some textbooks, however, describe dissection of these nodes as a standard technique. The present study was, therefore, undertaken to clarify which celiac nodes are regional for thoracic esophageal carcinoma and whether or not celiac node dissection would provide a survival benefit. Eight hundred and five patients who underwent R0 resection (no residual tumor) with systematic lymphadenectomy including the celiac axis area for thoracic esophageal carcinoma were retrospectively investigated. The frequency of metastasis and the therapeutic value of dissecting celiac nodes were compared to those associated with the left gastric artery area. The frequencies of left gastric and celiac nodal involvement were 15.4% and 9.6%, respectively, for thoracic esophageal carcinoma. As for tumor location, the incidences of metastasis around left gastric artery and celiac axis from the upper, middle and lower portion were 6.7% and 1.0%; 12.3% and 7.7%; and 25.7% and 17.4%, respectively. The 5-year survivals of patients with celiac but not left gastric metastasis were 36.3% and 41.8% for the middle and lower portions, respectively, while the corresponding values with left gastric involvement but no celiac metastasis were 24.1% and 27.9%. These differences were not significant. The frequency of celiac node involvement was not low. And, their dissection has equivalent therapeutic value to that of left gastric nodes. Revision of the TNM classification to account for celiac node involvement in thoracic esophageal carcinoma, especially of the middle and lower portions, is needed.