Clinical significance and role of lymphatic vessel invasion as a major prognostic implication in non-small cell lung cancer: a meta-analysis

Kallikrein-related peptidase 13 expression and clinicopathological features in lung squamous cell carcinoma

Lung squamous cell carcinoma (LSCC) is associated with poor prognosis. Molecular targeting drugs have been demonstrated to be effective for lung adenocarcinoma; however, they are often not effective for LSCC. Kallikrein-related peptidase 13 (KLK13) expression enhances the malignancy of lung adenocarcinoma; however, its expression and crucial role in LSCC remain largely unknown. The present study examined the relationship between the KLK13 expression and clinicopathological features of LSCC. A total of 94 patients diagnosed with LSCC who underwent lobectomy, segmentectomy or wedge resection were selected. KLK13 expression was evaluated through immunostaining of formalin-fixed paraffin-embedded sections of surgical specimens. Of the 94 LSCC samples, 70 exhibited no KLK13 expression, while the remaining 24 exhibited ectopic expression. KLK13 expression in tumors was focal and restricted to the cytoplasm of keratinized cells. LSCC cases were classified into KLK13-negative and KLK13-positive groups, and KLK13 expression was positively associated with E-cadherin expression (P=0.0143). Associations between KLK13 expression and keratinization (P=0.0052) or absence of lymphatic vessel invasion (P=0.0603) were observed; however, these trends did not reach statistical significance. The present findings indicated that KLK13 expression in keratinized LSCC may have a protective role in lymphatic vessel invasion of LSCC, which suggests its significance for therapeutic applications against LSCC.

Lymph but Not Blood Vessel Invasion Is Independent Prognostic in Lung Cancer Patients Treated by VATS-Lobectomy and Might Represent a Future Upstaging Factor for Early Stages

Lung cancer is the most frequent cause of cancer-related death worldwide. The patient’s outcome depends on tumor size, lymph node involvement and metastatic spread at the time of diagnosis. The prognostic value of lymph and blood vessel invasion, however, is still insufficiently investigated. We retrospectively examined the invasion of lymph vessels and blood vessels separately as two possible prognostic factors in 160 patients who underwent a video-assisted thoracoscopic lobectomy for non-small-cell lung cancer at our institution between 2014 and 2019. Lymph vessel invasion was significantly associated with the UICC stage, lymph node involvement, tumor dedifferentiation, blood vessel invasion and recurrence. Blood vessel invasion tended to be negative prognostic, but missed the level of significance (p = 0.108). Lymph vessel invasion, on the other hand, proved to be a prognostic factor for both histological subtypes, adenocarcinoma (p < 0.001) as well as squamous cell carcinoma (p = 0.018). After multivariate analysis apart from the UICC stage, only lymph vessel invasion remained independently prognostic (p = 0.018). Remarkably, we found analogue survival curve progressions of patients with stage I, with lymph vessel invasion, compared to stage II non-small-cell lung cancer. After further validation in prospective studies, lymph vessel invasion might be considered as an upstaging factor in resectable lung cancer. Especially in the early-stage of the disease, it might represent an additional risk factor to consider adjuvant therapy after surgical resection.

DeepCUBIT: Predicting Lymphovascular Invasion or Pathological Lymph Node Involvement of Clinical T1 Stage Non-Small Cell Lung Cancer on Chest CT Scan Using Deep Cubical Nodule Transfer Learning Algorithm

The prediction of lymphovascular invasion (LVI) or pathological nodal involvement of tumor cells is critical for successful treatment in early stage non-small cell lung cancer (NSCLC). We developed and validated a Deep Cubical Nodule Transfer Learning Algorithm (DeepCUBIT) using transfer learning and 3D Convolutional Neural Network (CNN) to predict LVI or pathological nodal involvement on chest CT images. A total of 695 preoperative CT images of resected NSCLC with tumor size of less than or equal to 3 cm from 2008 to 2015 were used to train and validate the DeepCUBIT model using five-fold cross-validation method. We also used tumor size and consolidation to tumor ratio (C/T ratio) to build a support vector machine (SVM) classifier. Two-hundred and fifty-four out of 695 samples (36.5%) had LVI or nodal involvement. An integrated model (3D CNN + Tumor size + C/T ratio) showed sensitivity of 31.8%, specificity of 89.8%, accuracy of 76.4%, and AUC of 0.759 on external validation cohort. Three single SVM models, using 3D CNN (DeepCUBIT), tumor size or C/T ratio, showed AUCs of 0.717, 0.630 and 0.683, respectively on external validation cohort. DeepCUBIT showed the best single model compared to the models using only C/T ratio or tumor size. In addition, the DeepCUBIT model could significantly identify the prognosis of resected NSCLC patients even in stage I. DeepCUBIT using transfer learning and 3D CNN can accurately predict LVI or nodal involvement in cT1 size NSCLC on CT images. Thus, it can provide a more accurate selection of candidates who will benefit from limited surgery without increasing the risk of recurrence.

Risk factors of lobar lymph node metastases in non-primary tumor-bearing lobes among the patients of non-small-cell lung cancer

Purpose

Lobar lymph node metastases in non-primary tumor-bearing lobes (NTBL) are rarely reported. This study examined the risk factors of lobar lymph node metastasis in NTBL.

Methods

We retrospectively studied 301 patients with non-small-cell lung cancer (NSCLC) who underwent surgical pulmonary resection with systematic lymph node dissection plus extended lobar lymph node dissection of NTBL. Patients were classified into positive and negative NTBL groups. Unconditional logistic regression was used to identify the risk factors for lobar lymph node metastasis in NTBL.

Results

NTBL lobar lymph nodes were identified in 38 patients (12.6%). A higher proportion of adenocarcinomas occurred in the positive NTBL group compared to the negative NTBL group (73.7% vs. 46.4%, P = 0.01). Risk of NTBL lobar lymph node metastases was significantly elevated in the lower lobe of primary site compared to the upper lobe (OR = 2.61, 95% CI = 1.26–5.75, P = 0.01), and with adenocarcinomas compared to squamous cell carcinomas (OR = 2.75, 95% CI = 1.09–7.65, P = 0.04). No differences were observed when comparing left and right lobes. NTBL lobar lymph node metastasis was most often observed among patients with larger tumor size, N1/N2 nodal involvement, with lymph vascular invasion (LVI), and visceral pleural invasion (VPI).

Conclusion

NTBL lobar lymph node metastases occurred more often in patients with a primary NSCLC tumor in the lower lobe, with adenocarcinomas, larger tumor size, N1/N2 nodal involvement, LVI or VPI. Extended lymphadenectomy including NTBL nodes may be clinically advantageous when these risk factors are present.

Prognostic markers in resected large cell neuroendocrine carcinoma: a multicentre retrospective analysis

Background

Large cell neuroendocrine carcinomas (LCNEC) are rare pulmonary malignancies. Reported survival rates are heterogeneous and the optimal therapeutic strategy is still debated. The prognosis of LCNEC is generally inferior compared to other non-small lung cancers. In early stages, surgery is recommended but might not be sufficient alone.

Methods

We retrospectively analyzed all consecutive LCNEC patients operated at three institutions with curative intent between May 2005 and January 2017. Data retrieved from individual clinical databases were analyzed with the aim to identify prognostic parameters.

Results

A total of 251 patients with LCNEC underwent curative intent surgery during the observation period. The median age was 64 years, 156 patients (62.2%) were male and 88.4% were smokers. The pathologic AJCC stage was I in 136 patients, II in 77, III in 33, and IV in 5 patients. Median follow-up was 26 months. Lymphatic vessel invasion (P=0.031) was identified as significant prognostic factor by multivariable analysis. There was a trend towards decreased survival in patients with blood vessel invasion (P=0.067). Even in earlier tumor stages, adjuvant chemotherapy had a positive effect on survival. The overall 1-, 3- and 5-year survival rates were 79.2%, 48.6% and 38.8% respectively.

Conclusions

Lymphatic invasion (L1) is an independent prognostic factor. Surgery in LCNEC is beneficial in early tumor stages and platinum-based adjuvant chemotherapy may help in achieving better long-term outcomes resulting in most obvious survival differences in stage Ib.

Postoperative chemoradiotherapy is superior to postoperative chemotherapy alone in squamous cell lung cancer patients with limited N2 lymph node metastasis

Background

The aim of the present study was to assess the efficacy of postoperative chemoradiotherapy (POCRT) following surgery in non-small-cell lung cancer patients with N2 lymph node metastasis (N2-NSCLC).

Methods

The clinical data of patients with N2-NSCLC treated with POCRT or postoperative chemotherapy (pCT) alone were retrospectively collected and reviewed. The overall survival (OS) rates were analyzed utilizing the Kaplan-Meier method and compared by the log-rank test. Cox regression analysis was used to determine factors significantly associated with survival. Propensity score matching (PSM) analysis was used to compensate for differences in baseline characteristics and OS was compared after matching.

Results

Between 2004 and 2014, a total of 175 patients fulfilled the inclusion criteria, 60 of whom were treated with POCRT, while 115 were administered pCT. The 1, 3 and 5-year OS rates in the POCRT and pCT groups were 98.3 vs. 86.1%, 71.7 vs. 53.0% and 45.7 vs. 39.0%, respectively (P = 0.019). Compared with pCT, POCRT improved OS in patients with squamous cell subtype (P = 0.010), no lymphovascular invasion (P = 0.006), pN2a (P = 0.006) or total number of metastatic lymph nodes ≤7 (P = 0.016). After PSM, these survival differences between POCRT and pCT remained significant in patients with squamous cell lung cancer (P = 0.010).

Conclusions

POCRT following complete resection may be beneficial for patients with squamous cell lung cancer, particularly those with limited nodal involvement.

Blood and lymphatic vessels contribute to the impact of the immune microenvironment on clinical outcome in non-small-cell lung cancer

OBJECTIVES

Lymphangiogenesis plays a critical role in the immune response, tumour progression and therapy effectiveness. The aim of this study was to determine whether the interplay between the lymphatic and the blood microvasculature, tumour-infiltrating lymphocytes and the programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) immune checkpoint constitutes an immune microenvironment affecting the clinical outcome of patients with non-small-cell lung cancer.

METHODS

Samples from 50 squamous cell carcinomas and 42 adenocarcinomas were subjected to immunofluorescence to detect blood and lymphatic vessels. CD3pos, CD8pos and PD-1pos tumour-infiltrating lymphocytes and tumour PD-L1 expression were assessed by immunohistochemical analysis.

RESULTS

Quantification of vascular structures documented a peak of lymphatics at the invasive margin together with a decreasing gradient of blood and lymphatic vessels from the peritumour area throughout the neoplastic core. Nodal involvement and pathological stage were strongly associated with vascularization, and an increased density of vessels was detected in samples with a higher incidence of tumour-infiltrating lymphocytes and a lower expression of PD-L1. Patients with a high PD-L1 to PD-1 ratio and vascular rarefaction had a gain of 10 months in overall survival compared to those with a low ratio and prominent vascularity.

CONCLUSIONS

Microvessels are an essential component of the cancer immune microenvironment. The clinical impact of the PD-1/PD-L1-based immune contexture may be implemented by the assessment of microvascular density to potentially identify patients with non-small-cell lung cancer who could benefit from immunotherapy and antiangiogenic treatment.

Impact of the epidermal growth factor receptor mutation status on the prognosis of recurrent adenocarcinoma of the lung after curative surgery

Background

The prognosis of patients with epidermal growth factor receptor (EGFR) mutant adenocarcinoma of the lung (Mt) and EGFR wild-type adenocarcinoma (Wt) after complete resection of the lung differ; however, the mechanisms responsible for these differences remain unclear. The present study examined the post-operative prognosis of recurrent pulmonary adenocarcinoma patients to evaluate the clinicopathological nature of Mt and contribution of EGFR - tyrosine kinase inhibitors (TKI) to the prognosis of patients.

Methods

The subjects were 237 patients with recurrent pulmonary adenocarcinoma who underwent EGFR mutation analysis, and consisted of 108 patients with recurrent Mt and 129 with recurrent Wt. Multivariate analyses were performed to investigate whether the EGFR status is a prognostic factor for relapse-free survival (RFS) and post-relapse survival (PRS).

Results

RFS was significantly better in Mt than in Wt patients; median RFS were 20.2 and 13.3 months, respectively (p < 0.001). The multivariate analysis identified EGFR mutation as an independent prognostic factor for a favorable RFS (hazard ratio = 0.68; 95% confidence interval, 0.52–0.89). Although, no significant differences were observed in PRS between Mt and Wt patients (median PRS were 33.9 and 28.2 months, respectively; p = 0.360), PRS was significantly better in Mt with EGFR - TKI than in Wt and Mt patients without EGFR - TKI (p = 0.008 and p < 0.001, respectively). PRS was also significantly better in Wt than in Mt patients without EGFR - TKI (p < 0.001). The multivariate analysis identified the administration of EGFR - TKI as an independent prognostic factor for PRS (hazard ratio = 0.60; 95% confidence interval, 0.40–0.89).

Conclusions

EGFR mutation tumors were associated with a significantly better RFS for recurrent pulmonary adenocarcinoma after curative resection of the lung, which represented the less aggressive nature of Mt tumors. However, patients with Mt did not have a favorable prognosis after recurrence unless they received EGFR - TKI.

Prognostic factors including lymphovascular invasion on survival for resected non-small cell lung cancer

OBJECTIVES

The aim of this study was to report on the influence of tumor lymphovascular invasion on overall survival and in patients with resected non-small cell lung cancer and identify prognostic factors for survival.

METHODS

This is a retrospective observational study of a consecutive series of patients who had surgical resection of non-small cell lung cancer in a single institution. The study covers a 3-year period. Overall survival was estimated by Kaplan-Meier method and multivariate Cox regression analysis was used to evaluate the relationship of lymphovascular invasion and other clinicopathologic variables. A multivariate regression was used to assess the relationship between tumor lymphovascular invasion and other clinical and pathologic characteristics.

RESULTS

A total of 524 patients were identified and included in the study. Two hundred twenty-five patients (43%) had tumors with lymphovascular invasion. Patients with tumor lymphovascular invasion had a lower overall survival (P < .0001). Tumor lymphovascular invasion was independently associated with visceral pleural involvement (P < .0001). In a multivariable model, lymphovascular invasion (hazard ratio [HR], 2.58; 95% confidence interval [CI], 1.63-4.09; P < .0001), parietal pleural invasion (HR, 45.4; 95% CI, 2.08-990; P = .015), advanced age (HR, 1.028; 95% CI, 1.009-1.048; P = .004), and N2 lymph node involvement (HR, 1.837; 95% CI, 1.257-2.690; P = .002) were independent prognostic factors for lower overall survival.

CONCLUSIONS

Lymphovascular invasion is associated with a worse overall survival in patients with resected non-small cell lung cancer regardless of tumor stage. Parietal pleural involvement, N2 nodal disease, and advanced age independently predict poor overall survival.

Difference in Postsurgical Prognostic Factors between Lung Adenocarcinoma and Squamous Cell Carcinoma

PURPOSE

The aim of this study was to compare the clinicopathologic prognostic factors between patients who underwent lung resection for adenocarcinoma (AD) and those with squamous cell carcinoma (SQ).

METHODS

A database of patients with lung AD or SQ who underwent surgery with curative intent in our department from January 2008 to December 2014 was reviewed. Associations between various clinicopathologic factors, postsurgical recurrence-free survival (RFS), and overall survival (OS) were analyzed to find significant prognostic factors.

RESULTS

A total of 537 lung cancer patients (AD, 434; SQ, 103) were included in this study. Although RFS was similar in patients with AD and SQ, OS was significantly poorer in those with SQ. Multivariate analysis in patients with AD revealed that age (≥69 vs. <69), lymphatic invasion, and histologic pleural invasion (p0 vs. p1-3) were associated with RFS, while gender and pleural invasion were associated with OS. In SQ, however, smoking, clinical stage, and pulmonary metastasis were associated with RFS in the multivariate analysis.

CONCLUSION

Since significant postoperative prognostic factors are quite different between lung AD and SQ, these two histologic types should be differently analyzed in a clinical study.

Vascular invasion is an adverse prognostic factor in resected non-small-cell lung cancer

Lung cancer is a leading cause of death, and there is a need for better prognostic factors in treatment decisions. Vascular invasion is a known negative prognosticator, but it is not clear how to evaluate this feature. Here, we studied the prevalence and prognostic impact of blood and lymphatic vascular invasion (BVI, LVI), tumour grade, necrosis, inflammation and pleural invasion on cancer-specific survival (LCSS) and time to recurrence (TTR) in non-small-cell lung cancer (NSCLC). A total of 438 patients surgically treated for NSCLC (1993-2010) were examined, including 213 adenocarcinomas (AC), 135 squamous cell carcinomas (SCC) and 90 other NSCLC. BVI and LVI were found in 25% and 21% of the cases, with reduced LCSS and TTR for both markers in AC and SCC (p < 0.005 for all). BVI and LVI remained independent prognostic factors for LCSS and TTR in separate multivariate models for AC and SCC. Combined BVI/LVI (7%) showed significantly reduced LCSS and TTR (p < 0.001), also by multivariate analysis. Our results support that BVI and LVI are valuable for prognostic staging. Vascular invasion identifies a group of patients at higher risk of recurrence and lung cancer-related death, and this could influence stratification of patients for treatment and follow-up.

Pretreatment Neutrophil to Lymphocyte Ratio Is Associated with Poor Survival in Patients with Stage I-III Non-Small Cell Lung Cancer

Background

Neutrophil-to-lymphocyte ratio (NLR) has been shown to be a prognostic indicator in several types of cancer. We aimed to investigate the association between NLR and survival in surgery-treated non-small cell lung cancer (NSCLC) patients.

Study Design

This large retrospective study included 1,245 patients who underwent initial surgery for stage I–III NSCLC at The University of Texas MD Anderson Cancer Center between December 2002 and November 2010. We analyzed the relationship of NLR with clinicopathological variables, local recurrence-free survival (LRFS), distant recurrence-free survival (DRFS), recurrence-free survival (RFS), overall survival (OS), and disease-specific survival (DSS) in patients with high or low NLR using Kaplan-Meier method. Hazard ratios (HRs) with 95% confidence intervals (CIs) were used to assess the prognostic strength of NLR.

Results

There was a statistically significant association between the pretreatment NLR and histology type (P = 0.003) and tumor grade (P = 0.028). At a median follow-up time of 50.6 months, high NLR was associated with reduced DRFS (P = 0.011), OS (P < 0.0001) and DSS (P = 0.004); it was not associated with LRFS and RFS. Multivariable Cox analysis further revealed that NLR (P = 0.027), pathologic stage (P < 0.0001) and lymphovascular invasion (P < 0.0001) were strong independent predictors for DRFS. NLR was also an independent marker predicting poor OS (P = 0.002) and DSS (P = 0.017).

Conclusion

The pretreatment NLR can serve as a biomarker to predict distant recurrence and death in stage I–III NSCLC patients. Combination of NLR and pathologic stage can better predict the OS and DSS in stage I-II NSCLC patients.

Results of surgical treatment and impact on T staging of non-small-cell lung cancer adjacent lobe invasion

OBJECTIVES

To assess the results of surgical treatment of T-ALI (adjacent lobe invasion) tumours in patients with non-small-cell lung carcinoma.

METHODS

Multicentric retrospective analysis of a prospectively maintained database of 13 065 patients, aged 32-89 years (mean 52.9, median 63 years), who underwent resection between January 2009 and September 2014.

RESULTS

In the whole study group, T-ALI was observed in 324 patients (2.5%): 201 patients (62.0%) with a tumour invading the pleura in the inter-lobar fissure (T-ALI-A), and 123 patients (38.0%) with a tumour in the adjacent lobe but without pleural invasion in the fissure (T-ALI-D). With regard to N0 patients, the 3- and 5-year survival rates in the T2 group were significantly higher than that of the T-ALI group (76.1 and 68.4%, P = 0.002 vs 58.3 and 51.0%, P = 0.008, respectively). On the other hand, when the N1 group was analysed, the 5-year survival rates were 54.3 and 48%, respectively (P = 0.041). In the N2 group, the 5-year survival rates in the T2 and T-ALI groups were 40.2 and 35.0%, respectively (P = 0.241). The comparison of the T-ALI and T3 groups for stages N0, N1 and N2 revealed differences in 5-year survival rates as follows: 68.4 vs 62.9% (P = 0.048), 48.0 vs 37.6% (P = 0.08) and 35.0 vs 27.6% (P = 0.121), respectively. In the whole group, the difference in survival rate between T-ALI N0 and T2N0 was statistically significant (P = 0.008) and statistically significant for the T3N0 group (P = 0.048). The 3-year survival rate in the T-ALI N0 group was statistically lower following pneumonectomy than following lobectomy (56.4 vs 61.3%, P = 0.03). The best survival rate was observed following bilobectomy (75.6%).

CONCLUSIONS

In our study, a tumour with ALI (T-ALI) represented a separate stage of cancer between T2 and T3. The survival rate in the T-ALI-A group was significantly poorer than that in the T-ALI-D group. Overall treatment results were similar for stage T3, suggesting that it may be necessary to divide this group into T3a and T3b. We would suggest that all tumours between 5 and 7 cm be classified as T3b, and any tumour smaller than 5 cm but with ALI be classified as T3a. Treatment of choice should include lobectomy or bilobectomy. Pneumonectomy should be performed only in a selected group of patients.

Prognostic impact of lymphatic invasion for pathological stage I squamous cell carcinoma of the lung

OBJECTIVE

The purpose of this study was to investigate the prognostic factors for pathological stage I squamous cell carcinoma of the lung to aid decisions regarding adjuvant chemotherapy.

METHODS

We retrospectively analyzed data from 114 consecutive patients with completely resected pathological stage I squamous cell carcinoma of the lung by lobectomy or segmentectomy with systematic lymphadenectomy.

RESULTS

The median tumor size was 2.9 cm. Lymphatic, vascular, and pleural invasions were present in 39 (34.2%), 50 (43.9%), and 25 (21.9%) patients, respectively. There were significant differences in recurrence-free and overall survival between patients with and without lymphatic invasion (P = 0.044 and P = 0.040, respectively). Multivariate Cox proportional hazards models demonstrated that postoperative complications (hazard ratio 3.37, 95% confidence interval 1.53-7.42, P = 0.003) and lymphatic invasion (hazards ratio 2.76, 95% confidence interval 1.26-6.04, P = 0.011) were independent prognostic factors influencing recurrence-free survival. Furthermore, age (hazard ratio 1.10, 95% confidence interval 1.02-1.18, P = 0.013) and lymphatic invasion (hazard ratio 3.54, 95% confidence interval 1.33-9.42, P = 0.011) were independent prognostic factors influencing overall survival.

CONCLUSIONS

Lymphatic invasion is an independent prognostic factor influencing both recurrence-free and overall survival in patients with pathological stage I squamous cell carcinoma of the lung. Patients with lymphatic invasion may be candidates for adjuvant chemotherapy.

PICT1 expression is a poor prognostic factor in non-small cell lung cancer

PICT1 is a key regulator of the MDM2–TP53 pathway. High mRNA expression levels of PICT1 are associated with poor prognosis in several cancers with wild-type TP53. In this study, we identified the PICT1 protein expression profile in non-small cell lung cancer (NSCLC) with wild-type TP53 in the nucleolus and cytoplasm, and revealed the relationship between PICT1 expression and patient clinicopathological factors. PICT1 expression in the tumor cells of 96 NSCLC patients with wild-type TP53 was evaluated by immunohistochemistry. Forty-three of 96 (44.8%) NSCLC samples were positive for nucleolar PICT1, while 40/96 (41.7%) NSCLC samples were positive for cytoplasmic PICT1. There was no correlation between nucleolar PICT1 expression and clinicopathological factors. However, cytoplasmic PICT1 expression was significantly correlated with sex, smoking history, differentiation, lymphatic invasion and pathological stage. In multivariate analysis, lymphatic invasion was significantly associated with cytoplasmic PICT1 expression (hazard ratio: 5.02, P = 0.026). We scrutinized PICT1 expression in samples of NSCLC with wild-type TP53, and showed a correlation between cytoplasmic PICT1 expression and several clinicopathological factors in these patients. Our results indicate that cytoplasmic PICT1 expression is a poor prognostic factor and is associated with tumor progression via lymphatic invasion in these patients.

Clinicopathology significance of podoplanin immunoreactivity in esophageal squamous cell carcinoma

BACKGROUD AND AIM

Podoplanin (D2-40) is a specific marker for lymphatic endothelium. The vast majority of previous studies on podoplanin immunostaining in esophageal squamous cell carcinoma (ESCC) focused on identifying lymphatic vessel invasion (LVI) and counting lymphatic vessel density (LVD) and had contradictory results. Recent studies show podoplanin expression on cancer cells or tumor stroma in several cancers, which have specific significance; but the status in ESCC remains unclear. Therefore, the aim of this study was to further study and summarize the clinicopathological significance of podoplanin immunoreactivity in ESCC.

MATERIALS AND METHODS

We examined podoplanin expression in tissue specimens from 107 patients with ESCC by immunohistochemistry. Podoplanin positive lymphatic vessels in intratumoral and peritumoral tissues and podoplanin positive expression in cancer cells and tumor stroma were analyzed, and correlated with clinicopathologic parameters and three-year overall and free-disease survival.

RESULTS

34 (31.8%) and 28 (26.2%) of 107 specimens had podoplanin positive expression in cancer cells and tumor stroma, respectively. Logistic regression analysis showed high intratumoral lymphatic vessel density (I-LVD) and podoplanin positivity in cancer cells were increased risks of lymph node metastasis (LNM) (OR=2.45, P=0.03; OR=0.35, P=0.01, respectively). Survival analysis showed that I-LVD was a significant factor related to poor three-year overall and free-disease survival (P=0.04, P=0.03, respectively).

CONCLUSIONS

Previous data and our results show that podoplanin seems to be a useful marker to predict LNM, recurrence, and worse prognosis in ESCC; in particular, LVI, high I-LVD, and podoplanin positivity in cancer cells are associated with LNM, recurrence and overall survival.

Significant increase in circulating tumour cells in pulmonary venous blood during surgical manipulation in patients with primary lung cancer

OBJECTIVES

Circulating tumour cells (CTCs) are tumour cells shed from a primary tumour and circulate in the peripheral blood after passing through the drainage vein. In previous studies, we showed that high numbers of CTCs were detected in the drainage pulmonary venous blood of most patients with resectable primary lung cancer, whereas only low numbers of CTCs were detected in the peripheral blood of some patients. Accordingly, this prospective study was conducted to assess changes in CTCs in the drainage pulmonary vein (PV) during lung cancer surgery.

METHODS

A total of 30 consecutive peripheral-type primary lung cancer patients who underwent lobectomy (or right upper and middle bilobectomy) through open thoracotomy were included. For each patient, 2.5 ml of blood was sampled from the lobar PV of the primary tumour site before and after surgical manipulation for lobectomy. The CTCs were evaluated quantitatively with the CellSearch® system.

RESULTS

Before surgical manipulation, CTCs were detected in PV blood in the majority of patients (22 of 30, 73.3%), although CTCs were detected in peripheral blood in only two patients (6.7%). The median number of CTCs in the PV (pvCTC-count) before surgical manipulation was 4.0 cells/2.5 ml, and there was no significant correlation between pvPV-count and any clinicopathological characteristic, including tumour size, progression and histological type. After surgical manipulation, at the time of completion of the lobectomy, the pvCTC-count significantly increased (median, 60.0 cells/2.5 ml; P = 0.001). The increase in pvCTC-count was significantly associated with microscopic lymphatic tumour invasion (ly); pvCTC-count significantly increased in ly-positive patients (pvCTC-count before and after surgical manipulation, 4.0 and 90.5 cells/2.5 ml, respectively; P = 0.006), but not in ly-negative patients (3.5 and 7.0 cells/2.5 ml, respectively; P = 0.153). The increase in pvCTC-count was not significantly associated with any other clinicopathological factor or with any surgical procedure, including the sequence of vessel interruption.

CONCLUSIONS

We documented a significant increase in CTC count in drainage PV blood after surgical manipulation, especially in tumours with lymphatic invasion. We are awaiting survival data at 5 year follow-up examination, which may provide clinical significance of the pvCTC-count.

[Lymphatic extension and lymphangiogenesis in non-small cell lung cancer]

Lymph node metastasis is a major adverse prognostic factor of malignant tumors, including non-small cell lung carcinoma (NSCLC). However the characterization of tumor associated lymphatic vessels and lymphangiogenic mediators in NSCLC are recent and their prognostic role is debated. Lymphatic vascular invasion (LVI) appears like a robust adverse prognostic factor when reported in NSCLC. This parameter should be better standardized and could be of use in adjuvant therapy indications. Moreover, anti-lymphangiogenesis therapies are currently under investigation and may become part of the anti-cancer strategy.