Oncological Significance of WHO Histological Thymoma Classification: A Clinical Study Based on 286 Patients

Meinoshin Okumura, Mitsunori Ohta, Shinichiro Miyoshi, Takashi Mori, Tsutomu Yasumitsu, Kazuya Nakahara, Keiji Iuchi, Hiroto Tada, Hajime Maeda, Hikaru Matsuda

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

Objectives: The clinical significance of thymoma histology remains controversial because of the numerous histological classifications of thymic epithelial tumors. Universal classification of such tumors was achieved by the World Health Organization (WHO) in 1999. We studied the prognostic significance of this classification. Methods: We studied clinical features and postoperative survival in cases of thymoma, but not thymic carcinoma, based on WHO histological classification in 286 patients undergoing surgery between 1958 and 2001. Results: Tumors were 19 type A, 79 type AB, 59 type B1, 102 type B2, and 27 type B3. The proportion of invasive tumors increased by type - from A to AB, B1, B2, and B3. The great vessels were involved more frequently in type B2 and B3 tumors than in type A, AB, and B1 tumors. The 20-year survival was 100% in type A, 87% in type AB, 91% in type B1, 65% in type B2, and 38% in type B3 tumors. Multivariate analysis showed Masaoka staging and WHO histological classification to be significant independent prognostic factors, while age, gender, myasthenia gravis association, resection completeness and great vessel involvement were not. In stage III patients, 13 of 45 patients with type B2 and B3 tumor died of their tumors, while no tumor deaths occurred in 11 patients with type A, AB, and B1 tumors. Conclusion: WHO histological classification realistically reflects the oncological behavior of thymoma.

Original languageEnglish
Pages (from-to)189-194
Number of pages6
JournalJapanese Journal of Thoracic and Cardiovascular Surgery
Volume50
Issue number5
Publication statusPublished - May 2002
Externally publishedYes

Fingerprint

Thymoma
Neoplasms
Clinical Studies
Survival
Myasthenia Gravis
Histology
Multivariate Analysis

Keywords

  • Masaoka staging
  • Thymic epithelial tumor
  • Thymoma
  • WHO histological classification

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Cite this

Okumura, M., Ohta, M., Miyoshi, S., Mori, T., Yasumitsu, T., Nakahara, K., ... Matsuda, H. (2002). Oncological Significance of WHO Histological Thymoma Classification: A Clinical Study Based on 286 Patients. Japanese Journal of Thoracic and Cardiovascular Surgery, 50(5), 189-194.

Oncological Significance of WHO Histological Thymoma Classification : A Clinical Study Based on 286 Patients. / Okumura, Meinoshin; Ohta, Mitsunori; Miyoshi, Shinichiro; Mori, Takashi; Yasumitsu, Tsutomu; Nakahara, Kazuya; Iuchi, Keiji; Tada, Hiroto; Maeda, Hajime; Matsuda, Hikaru.

In: Japanese Journal of Thoracic and Cardiovascular Surgery, Vol. 50, No. 5, 05.2002, p. 189-194.

Research output: Contribution to journalArticle

Okumura, M, Ohta, M, Miyoshi, S, Mori, T, Yasumitsu, T, Nakahara, K, Iuchi, K, Tada, H, Maeda, H & Matsuda, H 2002, 'Oncological Significance of WHO Histological Thymoma Classification: A Clinical Study Based on 286 Patients', Japanese Journal of Thoracic and Cardiovascular Surgery, vol. 50, no. 5, pp. 189-194.
Okumura, Meinoshin ; Ohta, Mitsunori ; Miyoshi, Shinichiro ; Mori, Takashi ; Yasumitsu, Tsutomu ; Nakahara, Kazuya ; Iuchi, Keiji ; Tada, Hiroto ; Maeda, Hajime ; Matsuda, Hikaru. / Oncological Significance of WHO Histological Thymoma Classification : A Clinical Study Based on 286 Patients. In: Japanese Journal of Thoracic and Cardiovascular Surgery. 2002 ; Vol. 50, No. 5. pp. 189-194.
@article{8ee6e78a4be5434683c68211ab9fb957,
title = "Oncological Significance of WHO Histological Thymoma Classification: A Clinical Study Based on 286 Patients",
abstract = "Objectives: The clinical significance of thymoma histology remains controversial because of the numerous histological classifications of thymic epithelial tumors. Universal classification of such tumors was achieved by the World Health Organization (WHO) in 1999. We studied the prognostic significance of this classification. Methods: We studied clinical features and postoperative survival in cases of thymoma, but not thymic carcinoma, based on WHO histological classification in 286 patients undergoing surgery between 1958 and 2001. Results: Tumors were 19 type A, 79 type AB, 59 type B1, 102 type B2, and 27 type B3. The proportion of invasive tumors increased by type - from A to AB, B1, B2, and B3. The great vessels were involved more frequently in type B2 and B3 tumors than in type A, AB, and B1 tumors. The 20-year survival was 100{\%} in type A, 87{\%} in type AB, 91{\%} in type B1, 65{\%} in type B2, and 38{\%} in type B3 tumors. Multivariate analysis showed Masaoka staging and WHO histological classification to be significant independent prognostic factors, while age, gender, myasthenia gravis association, resection completeness and great vessel involvement were not. In stage III patients, 13 of 45 patients with type B2 and B3 tumor died of their tumors, while no tumor deaths occurred in 11 patients with type A, AB, and B1 tumors. Conclusion: WHO histological classification realistically reflects the oncological behavior of thymoma.",
keywords = "Masaoka staging, Thymic epithelial tumor, Thymoma, WHO histological classification",
author = "Meinoshin Okumura and Mitsunori Ohta and Shinichiro Miyoshi and Takashi Mori and Tsutomu Yasumitsu and Kazuya Nakahara and Keiji Iuchi and Hiroto Tada and Hajime Maeda and Hikaru Matsuda",
year = "2002",
month = "5",
language = "English",
volume = "50",
pages = "189--194",
journal = "General Thoracic and Cardiovascular Surgery",
issn = "1863-6705",
publisher = "Springer Japan",
number = "5",

}

TY - JOUR

T1 - Oncological Significance of WHO Histological Thymoma Classification

T2 - A Clinical Study Based on 286 Patients

AU - Okumura, Meinoshin

AU - Ohta, Mitsunori

AU - Miyoshi, Shinichiro

AU - Mori, Takashi

AU - Yasumitsu, Tsutomu

AU - Nakahara, Kazuya

AU - Iuchi, Keiji

AU - Tada, Hiroto

AU - Maeda, Hajime

AU - Matsuda, Hikaru

PY - 2002/5

Y1 - 2002/5

N2 - Objectives: The clinical significance of thymoma histology remains controversial because of the numerous histological classifications of thymic epithelial tumors. Universal classification of such tumors was achieved by the World Health Organization (WHO) in 1999. We studied the prognostic significance of this classification. Methods: We studied clinical features and postoperative survival in cases of thymoma, but not thymic carcinoma, based on WHO histological classification in 286 patients undergoing surgery between 1958 and 2001. Results: Tumors were 19 type A, 79 type AB, 59 type B1, 102 type B2, and 27 type B3. The proportion of invasive tumors increased by type - from A to AB, B1, B2, and B3. The great vessels were involved more frequently in type B2 and B3 tumors than in type A, AB, and B1 tumors. The 20-year survival was 100% in type A, 87% in type AB, 91% in type B1, 65% in type B2, and 38% in type B3 tumors. Multivariate analysis showed Masaoka staging and WHO histological classification to be significant independent prognostic factors, while age, gender, myasthenia gravis association, resection completeness and great vessel involvement were not. In stage III patients, 13 of 45 patients with type B2 and B3 tumor died of their tumors, while no tumor deaths occurred in 11 patients with type A, AB, and B1 tumors. Conclusion: WHO histological classification realistically reflects the oncological behavior of thymoma.

AB - Objectives: The clinical significance of thymoma histology remains controversial because of the numerous histological classifications of thymic epithelial tumors. Universal classification of such tumors was achieved by the World Health Organization (WHO) in 1999. We studied the prognostic significance of this classification. Methods: We studied clinical features and postoperative survival in cases of thymoma, but not thymic carcinoma, based on WHO histological classification in 286 patients undergoing surgery between 1958 and 2001. Results: Tumors were 19 type A, 79 type AB, 59 type B1, 102 type B2, and 27 type B3. The proportion of invasive tumors increased by type - from A to AB, B1, B2, and B3. The great vessels were involved more frequently in type B2 and B3 tumors than in type A, AB, and B1 tumors. The 20-year survival was 100% in type A, 87% in type AB, 91% in type B1, 65% in type B2, and 38% in type B3 tumors. Multivariate analysis showed Masaoka staging and WHO histological classification to be significant independent prognostic factors, while age, gender, myasthenia gravis association, resection completeness and great vessel involvement were not. In stage III patients, 13 of 45 patients with type B2 and B3 tumor died of their tumors, while no tumor deaths occurred in 11 patients with type A, AB, and B1 tumors. Conclusion: WHO histological classification realistically reflects the oncological behavior of thymoma.

KW - Masaoka staging

KW - Thymic epithelial tumor

KW - Thymoma

KW - WHO histological classification

UR - http://www.scopus.com/inward/record.url?scp=0036580514&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0036580514&partnerID=8YFLogxK

M3 - Article

C2 - 12048910

AN - SCOPUS:0036580514

VL - 50

SP - 189

EP - 194

JO - General Thoracic and Cardiovascular Surgery

JF - General Thoracic and Cardiovascular Surgery

SN - 1863-6705

IS - 5

ER -