Siewert III esophagogastric junction adenocarcinoma: does TNM 8th save us?
Siewert III cancers were classified as esophageal cancers by the TNM 7th edition (TNM7), while being defined as gastric cancers by the new TNM 8th edition (TNM8). Aim of this study was to compare previous and present TNM classifications of Siewert III. From 2000 to 2015, 309 patients with Siewert III adenocarcinoma were treated at ten high-volume centers, belonging to the GIRCG (Italian Research Group for Gastric Cancer). We retrospectively analyzed overall survival according to TNM classifications: gastric TNM8 was compared with either gastric TNM7 or esophageal TNM7. Median number of lymph nodes harvested was 31 (interquartile range 22–44). Agreement between gastric TNM7 and TNM8 was very good (weighted kappa 92.3%, IC 95% 90.3–94.1%). Accordingly, stage migration was observed in 54 of 309 patients (17.5%), with 12 patients upstaged (3.9%) and 42 downstaged (13.6%). Cox models including either gastric TNM7 or TNM8 achieved similar goodness-of-fit and c-index. Differences were much larger, when shifting from esophageal TNM7 to gastric TNM8: the agreement was much lower (weighted kappa 69.1%, 65.2–73.2%), with 196 of 309 patients (63.4%) downstaging. The corresponding Cox model presented the lowest goodness-of-fit and discrimination ability. Gastric TNM7 and TNM8 were largely superimposable, so that stage migration was minor and prognostic significance was similar. At variance, stage migration was substantial when shifting from esophageal TNM7 to TNM8. Moreover, survival models with esophageal TNM7 presented the worst goodness-of-fit and the lowest discrimination ability. This further supports placing Siewert III among gastric cancers, as done in TNM8.
KeywordsSiewert III EGJ Esophageal TNM7 Gastric TNM7 Gastric TNM8
We thank Giovanni Vittimberga (General Surgery, Morgagni-Pierantoni Hospital, Forlì, Italy), Fausto Rosa (Division of Digestive Surgery, Department of Surgical Sciences, Catholic University, Rome, Italy), Giovanni Sgroi (Department of General Surgery, Treviglio Hospital, ASST of Bergamo, Bergamo, Italy) and Francesco Ricci (Unit of General Surgery, Rovereto Hospital (APSS of Trento), Italy) for their precious participation in this study.
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Conflict of interest
The authors declare that they have no conflicts of interest.
Human participants and/or animals statement
The research does not involve human participants and/or animals.
There was no need to get informed consent.
- 2.Lutz MP, Zalcberg JR, Ducreux M et al (2012) Highlights of the EORTC st. Gallen international expert consensus on the primary therapy of gastric, gastroesophageal and oesophageal cancer—differential treatment strategies for subtypes of early gastroesophageal cancer. Eur J Cancer 48(16):2941–2953. https://doi.org/10.1016/j.ejca.2012.07.029 CrossRefPubMedGoogle Scholar
- 3.Ajani JA, D’Amico TA, Almhanna K, et al (2015) Esophageal and esophagogastric junction cancers, version 1.2015. J Natl Compr Cancer Netw 13(2):195–227Google Scholar
- 5.Brierley JD, Gospodarowicz MKWC (2017) TNM classification of malignant tumours, 8th edn. Wiley-Blackwell, OxfrodGoogle Scholar
- 7.Kim SG, Seo HS, Lee HH, Song KY, Park CH (2017) Comparison of the differences in survival rates between the 7th and 8th editions of the AJCC TNM staging system for gastric adenocarcinoma: a single-institution study of 5,507 patients in korea. J Gastric Cancer 17(3):212–219. https://doi.org/10.5230/jgc.2017.17.e23 CrossRefPubMedPubMedCentralGoogle Scholar
- 8.Lu J, Zheng C, Cao L et al (2017) The effectiveness of the 8th American Joint Committee on Cancer TNM classification in the prognosis evaluation of gastric cancer patients: A comparative study between the 7th and 8th editions. Eur J Surg Oncol. https://doi.org/10.1016/j.ejso.2017.09.001 Google Scholar
- 19.Shen Z, Ye Y, Xie Q, Liang B, Jiang K, Wang S (2015) Effect of the number of lymph nodes harvested on the long-term survival of gastric cancer patients according to tumor stage and location: a 12-year study of 1,637 cases. Am J Surg 210(3):431–440. https://doi.org/10.1016/j.amjsurg.2015.01.029 CrossRefPubMedGoogle Scholar