Lung tumor
Other carcinoma
Bronchioloalveolar carcinoma

Author: Deepali Jain, M.D. (see Authors page)

Revised: 21 December 2016, last major update September 2012

Copyright: (c) 2003-2016, PathologyOutlines.com, Inc.

PubMed Search: bronchioloalveolar carcinoma[title] lung
Cite this page: Bronchioloalveolar carcinoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/lungtumorBAL.html. Accessed February 20th, 2017.
Definition / General
  • Refers to growth pattern called lepidic, which arises from and spreads along alveolar walls without invasion
  • Similar to jagziekte, a disease of South African sheep, but jagziekte DNA not identified in human tumors
  • IASLC / ATS / ERS classification (Mod Pathol 2011;24:653): BAC no longer a valid diagnosis
  • WHO definition: adenocarcinoma with bronchioloalveolar pattern and no evidence of stromal, vascular, or pleural invasion, based on complete resection specimen
Bronchioloalveolar carcinoma: how to classify tumors now
    1. ≤ 3 cm, NO stromal, lymphatic, vascular or pleural invasion, no necrosis, no growth patterns other than lepidic:
    • Adenocarcinoma in situ, either serous or mucinous

    2. ≤ 3 cm, with ≤ 5 mm area of stromal invasion or growth pattern(s) other than lepidic:
    • Minimally Invasive Adenocarcinoma (MIA)

    3. > 3 cm OR lymphatic, vascular or pleural invasion OR necrosis OR > 5 mm area of stromal invasion OR growth pattern(s) other than lepidic:
    • Serous: invasive adenocarcinoma, lepidic predominant or
    • Mucinous: invasive mucinous adenocarcinoma

  • Invasion defined as histological subtypes other than lepidic or presence of a myofibroblastic stroma associated invasive tumor
  • For tumors with multiple foci, measure largest dimension on a single slide; do NOT sum invasive foci on all slides
Micro Images

Images hosted on other servers:

Noninvasive

Bronchioloalveolar cell adenocarcinoma of the lung

Carcinoma in situ arising in bronchiolar metaplasia co-existing with invasive adenocarcinoma