The Prognostic Significance of Lymphovascular Invasion on Biopsy Specimens in Lung Cancer Treated With Definitive Chemoradiotherapy

ERG Immunohistochemistry as an Endothelial Marker for Assessing Lymphovascular Invasion

Background

ERG, a member of the ETS family of transcription factors, is a highly specific endothelial marker. We investigated whether the use of ERG immunostaining can help pathologists detect lymphovascular invasion (LVI) and decrease interobserver variability in LVI diagnosis.

Methods

Fifteen cases of surgically resected colorectal cancers with hepatic metastasis were selected and the most representative sections for LVI detection were immunostained with ERG, CD31, and D2-40. Eight pathologists independently evaluated LVI status on hematoxylin and eosin (H&E) and the corresponding immunostained sections and then convened for a consensus meeting. The results were analyzed by kappa (κ) statistics.

Results

The average rate of LVI positivity was observed in 43% with H&E only, 10% with CD31, 29% with D2-40, and 16% with ERG. Agreement among pathologists was fair for H&E only (κ=0.27), D2-40 (κ=0.21), ERG (κ=0.23), and was moderate for CD31 (κ=0.55). Consensus revealed that ERG nuclear immunoreactivity showed better visual contrast of LVI detection than the other staining, with improved agreement and LVI detection rate (κ=0.65, LVI positivity rate 80%).

Conclusions

The present study demonstrated a superiority with ERG immunostaining and indicated that ERG is a promising panendothelial marker that might help pathologists increase LVI detection and decrease interobserver variability in LVI diagnosis.

Lymphovascular invasion in non-small-cell lung cancer: implications for staging and adjuvant therapy

BACKGROUND

Lymphovascular space invasion (LVI) is an established negative prognostic factor and an indication for postoperative radiation therapy in many malignancies. The purpose of this study was to evaluate LVI in patients with early-stage non-small-cell lung cancer, undergoing surgical resection.

METHODS

All patients who underwent initial surgery for pT1-3N0-2 non-small-cell lung cancer at Duke University Medical Center from 1995 to 2008 were identified. A multivariate ordinal regression was used to assess the relationship between LVI and pathologic hilar and/or mediastinal lymph node (LN) involvement. A multivariate Cox regression analysis was used to evaluate the relationship of LVI and other clinical and pathologic factors on local failure (LF), freedom from distant metastasis (FFDM), and overall survival (OS). Kaplan-Meier methods were used to generate estimates of LF, FFDM, and OS in patients with and without LVI.

RESULTS

One thousand five hundred and fifty-nine patients were identified. LVI was independently associated with the presence of regional LN involvement (p < 0.001) along with lobar (versus sublobar) resections (p < 0.001), and an open thoracotomy (versus video-assisted thoracoscopic surgery). LVI was not independently associated with LF on multivariate analysis (hazard ratio [HR] = 1.23, p = 0.25), but was associated with a lower FFDM (HR 1.52, p = 0.005) and OS (HR 1.26, p = 0.015). In addition, multivariate analysis showed that LVI was strongly associated with increased risk of developing distant metastases (HR = 1.75, p = 0.006) and death (HR = 1.53, p = 0.003) in adenocarcinomas but not in squamous carcinomas.

CONCLUSIONS

LVI is associated with an increased risk of harboring regional LN involvement. LVI is also an adverse prognostic factor for the development of distant metastases and long-term survival.