Proposed modification of the eighth edition of the AJCC-ypTNM staging system of esophageal squamous cell cancer treated with neoadjuvant chemotherapy: Unification of the AJCC staging system and the Japanese classification

Taro Oshikiri; Hironobu Goto; Takashi Kato; Ryuichiro Sawada; Hitoshi Harada; Naoki Urakawa; Hiroshi Hasegawa; Shingo Kanaji; Kimihiro Yamashita; Takeru Matsuda; Yasuhiro Fujino; Masahiro Tominaga; Yoshihiro Kakeji

doi:10.1016/j.ejso.2022.01.014

Proposed modification of the eighth edition of the AJCC-ypTNM staging system of esophageal squamous cell cancer treated with neoadjuvant chemotherapy: Unification of the AJCC staging system and the Japanese classification

Eur J Surg Oncol. 2022 Aug;48(8):1760-1767. doi: 10.1016/j.ejso.2022.01.014. Epub 2022 Jan 20.

Authors

Affiliations

¹ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: oshikiri@med.kobe-u.ac.jp.
² Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: hirogoto@med.kobe-u.ac.jp.
³ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: kato0215@med.kobe-u.ac.jp.
⁴ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: rsawada@med.kobe-u.ac.jp.
⁵ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: htharada@med.kobe-u.ac.jp.
⁶ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: urakawa@med.kobe-u.ac.jp.
⁷ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: hasega@med.kobe-u.ac.jp.
⁸ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: kanashin@med.kobe-u.ac.jp.
⁹ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: kiyama@med.kobe-u.ac.jp.
¹⁰ Division of Minimally Invasive Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: tmatsuda@med.kobe-u.ac.jp.
¹¹ Department of Gastroenterological Surgery, Hyogo Cancer Center, 13-70, Kitaoji-cho, Akashi, Hyogo, 673-8558, Japan. Electronic address: yasu120@hp.pref.hyogo.jp.
¹² Department of Gastroenterological Surgery, Hyogo Cancer Center, 13-70, Kitaoji-cho, Akashi, Hyogo, 673-8558, Japan. Electronic address: tomimasa-08@hp.pref.hyogo.jp.
¹³ Division of Gastrointestinal Surgery, Department of Surgery, Graduate School of Medicine, Kobe University, 7-5-2, Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. Electronic address: kakeji@med.kobe-u.ac.jp.

PMID: 35094909
DOI: 10.1016/j.ejso.2022.01.014

Abstract

Background: The eighth edition of the American Joint Committee on Cancer (AJCC) tumor node metastasis (AJCC-TNM 8th) system adopted the newly separate post-neoadjuvant pathologic stage group (ypTNM). However, it is not compatible with the Japanese pathologic classification after neoadjuvant chemotherapy (JPN-CT-pTNM). The aim of this study is to clarify the subjects of the AJCC-ypTNM 8th and propose a unification of the AJCC and Japanese systems to create novel AJCC-CT-pTNM 8th.

Methods: Participants were 304 esophageal squamous cell carcinoma (ESCC) patients who underwent neoadjuvant chemotherapy followed by 3 stage esophagectomy between 2010 and 2019. Predictive probabilities of pN, pM in AJCC-ypTNM 8th and JPN-CT-pTNM 11th systems were evaluated to propose novel system.

Results: In training data from 234 patients, the overall survival rate was statistically better for ypStage IIIA than ypStage II (P = 0.040) resulting in staging inversion in AJCC-ypTNM 8th. Predictive probability of pathological N status in AJCC-ypTNM 8th (Akaike Information Criterion: AIC = 979.53) was superior to that in JPN-CT-pTNM 11th (AIC = 999.07). In AJCC-ypTNM 8th, 71% (15/21) of ypM1 diseases were supraclavicular lymph nodes (No. 104 L/N as regional in JPN-CT-pTNM 11th) metastases with considerably good prognosis. The predictive probability of the novel AJCC-CT-pTNM 8th [unification of ypStage II and IIIA, conversion of supraclavicular L/Ns metastases from ypM to ypN] (AIC = 1054.24) was superior to that of the existing AJCC-ypTNM 8th (AIC = 1070.74). The feasibility of novel system was validated using test data from 70 patients.

Conclusions: Unification of the AJCC and Japanese systems yields a simpler and more precise predictive system after neoadjuvant chemotherapy.

Keywords: AJCC-CT-TNM 8th; American Joint committee on cancer (AJCC); Esophageal squamous cell carcinoma (ESCC); Japanese classification; Post-neoadjuvant tumor node metastasis (ypTNM) staging.

MeSH terms

Carcinoma, Squamous Cell* / pathology
Epithelial Cells / pathology
Esophageal Neoplasms* / drug therapy
Esophageal Neoplasms* / pathology
Esophageal Squamous Cell Carcinoma* / pathology
Esophageal Squamous Cell Carcinoma* / therapy
Humans
Neoadjuvant Therapy
Neoplasm Staging
Prognosis
Retrospective Studies