Factors Influencing the Diagnostic Accuracy of Identifying the Histologic Type of Non--Small-Lung Cancer With Small Samples.
BACKGROUND
The pathologic diagnosis has become a greater consideration in decision-making regarding the treatment options for lung cancer. Therefore, the accurate diagnosis of the tumor histologic type is essential, even when only small biopsy or cytology samples are available. However, the risk of a misdiagnosis with smaller biopsy samples is greater. The factors underlying the increased risk of a misdiagnosis in small samples are unknown. The aim of the present study was to identify the clinical and pathologic factors (other than immunohistochemical staining) that influence the pathologic diagnostic accuracy in small biopsy and cytological lung samples obtained by bronchoscopy.


METHODS
We performed transbronchial lung biopsy or brushing and lavage to determine the preoperative diagnosis of 126 of 299 surgically resected lung cancer specimens. We assessed the diagnostic accuracy of the preoperative transbronchoscopic examination findings against that of the surgically resected lung specimens.


RESULTS
On univariate analysis, the mean pathologic tumor size in the noncorresponding cases was larger than that in corresponding cases. Vascular invasion was also more prevalent in the noncorresponding cases. The tumor differentiation grade in the noncorresponding cases was poorer than in the corresponding cases. The noncorresponding cases were at a more progressed stage. On multivariate analysis, the pathologic tumor size and tumor differentiation grade were associated with the noncorresponding cases.


CONCLUSIONS
We found a larger tumor size and poor differentiation grade were indicative of lung cancer tissue with a greater content of heterogeneous cells. Therefore, a possibility exists of a false diagnosis using only these factors. Thus, treatment decisions should be made considering the pathologic diagnosis and other relevant factors.
Division of Thoracic Surgery, Chemotherapy Research Institute, Kaken Hospital, Ichikawa-shi, Japan. Electronic address: take.oikawa@gmail.com.
Takefumi
T
Oikawa
Division of Thoracic Surgery, Tokyo Medical University, Tokyo, Japan.
Tatsuo
T
Ohira
Division of Anatomic Pathology, Tokyo Medical University, Tokyo, Japan.
Jun
J
Matsubayashi
Division of Thoracic Surgery, Chemotherapy Research Institute, Kaken Hospital, Ichikawa-shi, Japan.
Chimori
C
Konaka
Division of Thoracic Surgery, Tokyo Medical University, Tokyo, Japan.
Norihiko
N
Ikeda
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D009367:Neoplasm Staging
Large tumor size; Poor differentiation grade; Postoperative diagnosis; Preoperative diagnosis; Risk factor