title: [Atypical adenomatous hyperplasia of lung: clinicopathologic study of 8 cases and review of literature].
abstract: OBJECTIVE
  To study the clinicopathologic and immunohistochemical features of atypical adenomatous hyperplasia (AAH) of lung.
  
  
  METHODS
  Eight cases of AAH of lung were studied by light microscopy and immunohistochemical staining for p16, thyroid transcription factor-1 (TTF-1), Ki-67, p53, epidermal growth factor receptor (EGFR) and c-erbB-2.
  
  
  RESULTS
  The mean age of the patients was 52 years. The male-to-female ratio was 1:3. Two patients were chronic smokers. The clinical symptoms were relatively non-specific. Three patients had past history of non-pulmonary tumors, while 4 patients had lung adenocarcinoma. CT scan revealed solitary or multifocal hyperdense opacities. Histologically, the lesions ranged from 1 mm to 6 mm in size. Two cases were solitary and 6 cases were multifocal. All were of high-grade lesions. Associated low-grade component was noted in 3 cases. There was no evidence of local recurrence or disease progression in the 7 patients with post-operative follow-up information available (mean duration of follow up = 23 months). Four patients had received chemotherapy as well. Immunohistochemical study showed variable positivity for p16 (5/8), TTF-1 (5/8), Ki-67 (with proliferation index ranging from 1% to 10%), p53 (1/8) and EGFR (1/8). The staining for c-erbB-2 was negative (0/8). Four cases of AAH were associated with pulmonary adenocarcinoma. The adenocarcinoma cells were diffusely positive for TTF-1 (4/4), variably positive for p16 (2/4), Ki-67 (with proliferation index ranging from 2% to 40%), p53 (1/4) and EGFR (3/4), and negative for c-erbB-2 (0/4).
  
  
  CONCLUSIONS
  AAH of lung is associated with pulmonary adenocarcinoma. Diagnosis of AAH requires correlation with CT findings and pathologic examination.
authors: Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors: Zhen
authors: Z
authors: Huo
authors: Hong-rui
authors: HR
authors: Liu
authors: Jian-wei
authors: JW
authors: Wan
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D018255:Adenomatosis, Pulmonary / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D000328:Adult; D019941:Cyclin-Dependent Kinase Inhibitor p16; D004268:DNA-Binding Proteins / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006965:Hyperplasia / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D019394:Ki-67 Antigen / Q000378:metabolism; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism; D009378:Neoplasms, Multiple Primary / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D011230:Precancerous Conditions / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D014157:Transcription Factors
chemical_list: C000614131:CDKN2A protein, human; D019941:Cyclin-Dependent Kinase Inhibitor p16; D004268:DNA-Binding Proteins; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; C504003:TTF1 protein, human; D014157:Transcription Factors