Study confirms prognostic value of new IASLC/ATS/ERS adenocarcinoma sub-classification

The International Association for the Study of Lung Cancer (IASLC), the American Thoracic Society (ATS), and the European Respiratory Society (ERS), have proposed a new sub-classification of lung adenocarcinomas. A growing number of publications from Australia, Germany and South America have validated the new sub-classification. However, there are only few reports of this type of validation for the Asian population. A new study published in the January 2013 issue of the International Association for the Study of Lung Cancer's (IASLC) Journal of Thoracic Oncology, concludes the new IASLC/ATS/ERS classification identifies histologic subtypes of lung adenocarcinomas with prognostic value among Japanese patients.

Researchers looked at patients with lung adenocarcinoma who underwent pul¬monary resection between January 2001 and December 2009 at Kyoto University Hospital, Japan. The histological investigation included 440 lung adenocarcinomas, which met the 2004 WHO crite¬ria for primary lung adenocarcinoma. Tumor staging was performed according to the 7th edition of the tumor, node, metastasis classification of the International Union Against Cancer.

Researchers concluded that the new classification identifies histologic subtypes of lung adenocarcinomas with prognostic value among Japanese patients. Moreover, they say, "EGFR mutations were significantly identified in AIS/MIA/Lepidic/Pap subtypes. Conversely, KRAS mutations were frequently identified in mucinous sub¬types."

On the basis of these findings, they conclude, "that histologic subtyping and molecular testing for EGFR and KRAS muta¬tions are helpful for predicting prognosis among patients with resectable lung cancer and may be helpful in selecting patients who require adjuvant chemotherapy."

The lead author of this work is Dr. Akihiko Yoshizawa. Co-authors include IASLC members Dr. Masashi Kobayashi, Dr. William Travis and Dr. Hiroshi Date.