Complex Glands (Cribriform and Fused Glands) Are Patterns of High Grade Adenocarcinoma in the Lung
Philippe Joubert, Natasha Rekhtman, Andre L Moreira. Memorial Sloan-Kettering Cancer Center, New York, NY
Background: The recently proposed IASLC/ATS/ERS classification of pulmonary adenocarcinoma has a prognostic value by classifying the heterogeneous adenocarcinomas according to the predominant component of the tumor. The classification recognizes 5 patterns of adenocarcinoma: lepidic, acinar, papillary, solid, and micropapillary. Furthermore, an independent grading system for lung adenocarcinomas was recently proposed which is based on a combination of the two most predominant amounts of these 5 patterns. However, the occurrence of other patterns that do not fit into these defined morphologies poses a challenge for applying this classification and grading systems.
Design: 283 resected pulmonary adenocarcinomas were reviewed and classified according to above systems. The amounts of the standard 5 patterns as well as non-standard patterns, including cribriform, ragged/fused glands were recorded for each case. The association of non-standard patterns with the predominant type of adenocarcinoma, tumor grade, and disease free survival (DFS) were evaluated.
Results: Ragged/fused glands and cribriform pattern were seen in 28%, 18.7% of cases, respectively. The amount of cribriform and ragged/fused glands ranged from 10 to 100% of the entire tumor. Ragged/fused glands and cribriform patterns were associated with solid growth pattern (p<0.001 Fisher exact test) and high tumor grade (P<0.0001 Fisher exact test). Disease-free survival for tumors containing complex glandular patterns was similar to high grade tumors (log rank p= 0.8523), and significantly worse than low-grade tumors.
Conclusions: It is important to recognize the presence of these variant patterns of adenocarcinoma, which should be considered as patterns of high grade adenocarcinoma and not be interpreted as acinar adenocarcinoma which is prognostically a pattern of intermediate grade.
Monday, March 4, 2013 2:30 PM
Proffered Papers: Section D, Monday Afternoon