Relationships between radiosensitivity and microvascular density in esophageal carcinoma: significance of hypoxic fraction

Association between pathological infiltrative tumor growth pattern and prognosis in patients with resected lung squamous cell carcinoma

INTRODUCTION

Lung squamous cell carcinoma (LUSC) usually shows expansive growth with large tumor nests; few reports on invasive growth patterns (INF) in LUSC have been associated with poor prognosis in gastrointestinal and urothelial cancers. In this study, we examine the association between INF and the prognosis of LUSC.

MATERIALS AND METHODS

We analyzed INF as a potential prognostic factor in 254 consecutive patients with LUSC who underwent complete surgical resection at our hospital between 2008 and 2017. INF was classified into 3 categories based on the structure of the tumor other than the large round solid nest of tumor cells.

RESULTS

INF was categorized as INFa in 59 patients (23 %) with only well-demarcated large solid tumor cell nests, INFb in 89 patients (35 %) with medium to small, alongside large solid nests, and INFc in 98 patients (39 %) with cord-like/small nests or isolated cells plus large or medium solid nests. No significant lymph node metastasis differences were observed between INFc and INFa/b tumors. However, in patients with p-stage I, INFc had a poorer prognosis with regard to recurrence-free survival (RFS), with a 5-year RFS rate of 53.3 %, compared to 74.9 % for INFa/b (p = 0.010).

CONCLUSION

Our study highlights a novel pathological concept of INF in LUSC, and contributed to the proposal that it is a factor indicating an unfavorable prognosis in patients with early-stage LUSC. A prospective multicenter study is warranted for INFc patients, as careful follow-up and adjuvant chemotherapy might lead to the early detection and prevention of recurrence.

Clinical significance of evaluating endoscopic response to neoadjuvant chemotherapy in esophageal squamous cell carcinoma

BACKGROUND AND AIM

Clinical significance of endoscopic response (ER) after neoadjuvant chemotherapy (NAC) for esophageal cancer has not been fully understood. Thus, the present study aimed to investigate the association between ER to NAC and its clinicopathological outcomes in patients with esophageal squamous cell carcinoma (ESCC).

METHODS

In total, 141 patients who underwent NAC and subsequent esophagectomy for ESCC were included. ER to NAC was retrospectively evaluated based on macroscopic findings of the primary tumor, which was classified into three categories: endoscopic no response (eNR), endoscopic partial response (ePR), and endoscopic good response (eGR). An endoscopic responder was defined as patients with eGR/ePR.

RESULTS

Approximately 89.4% of patients had cStage II-III disease, and 7.1% had pathological complete response. Upon ER evaluation, eNR, ePR, and eGR were observed in 46 (32.6%), 54 (38.3%), and 41 (29.1%) patients, respectively. Pathological responders significantly increased as the ER grade became better. Among preoperative clinical factors, only ER significantly correlated with pathological response in univariate and multivariate analysis. Endoscopic responders showed a significantly better prognosis than did eNR patients (P < 0.001), although the overall survival (OS) of the patients with eGR and ePR was equivalent. Endoscopic responder, ypT, ypN, and pathological responder were significant predictors of OS in the univariate analysis, and endoscopic responder, ypN, and pathological responder were independent predictors in the multivariate analysis.

CONCLUSION

This study suggests that ER can be a simple and important tool to predict the pathological response and survival of patients who undergo NAC for ESCC.

Carbon ion radiotherapy: impact of tumor differentiation on local control in experimental prostate carcinomas

Background

To summarize the research activities of the “clinical research group heavy ion therapy”, funded by the German Research Foundation (DFG, KFO 214), on the impact of intrinsic tumor characteristics (grading, hypoxia) on local tumor control after carbon (¹²C-) ion- and photon irradiations.

Methods

Three sublines of syngeneic rat prostate tumors (R3327) with various differentiation levels (highly (-H), moderately (-HI) or anaplastic (-AT1), (diameter 10 mm) were irradiated with 1, 2 and 6 fractions of either ¹²C-ions or 6 MV photons using increasing dose levels. Primary endpoint was local tumor control at 300 days. The relative biological effectiveness (RBE) of ¹²C-ions was calculated from TCD₅₀-values (dose at 50% tumor control probability) of photons and ¹²C-ions and correlated with intrinsic tumor parameters. For the HI-subline, larger tumors (diameter 18 mm) were irradiated with either carbon ions, oxygen ions or photons under ambient as well as hypoxic conditions to determine the variability of the RBE under different oxygenation levels. In addition, imaging, histology and molecular analyses were performed to decipher the underlying mechanisms.

Results

Experimental results revealed (i) a smaller variation of the TCD₅₀-values between the three tumor sublines for ¹²C-ions (23.6 - 32.9 Gy) than for photons (38.2 - 75.7 Gy), (ii) steeper dose-response curves for ¹²C-ions, and (iii) an RBE that increased with tumor grading (1.62 ± 0.11 (H) vs 2.08 ± 0.13 (HI) vs 2.30 ± 0.08 (AT1)). Large HI-tumors resulted in a marked increase of TCD₅₀, which was increased further by 15% under hypoxic relative to oxic conditions. Noninvasive imaging, histology and molecular analyses identified hypoxia as an important radioresistance factor in photon therapy.

Conclusions

The dose-response studies revealed a higher efficacy of ¹²C-ions relative to photon therapy in the investigated syngeneic tumor model. Hypoxia turned out to be at least one important radioresistance factor, which can be partly overridden by high-LET ion beams. This might be used to increase treatment effectiveness also in patients. The results of this project served as a starting point for several ongoing research projects.

The relationship between GLUT-1 and vascular endothelial growth factor expression and 18F-FDG uptake in esophageal squamous cell cancer patients

PURPOSE

To examine the relationship between glucose transporter-1 (GLUT-1) and vascular endothelial growth factor (VEGF) expression and (18)F-FDG uptake in esophageal squamous cell cancer patients.

MATERIALS AND METHODS

Fifty-seven patients (52 male and 5 female) were included in this study. (18)F-FDG PET/CT was performed prior to the surgery. Immunohistochemistry was performed using postoperative histopathological specimens. The estimation of immunohistochemistry was conducted using scoring analysis. We investigated the correlations between maximum standardized uptake value (SUV(max)) and GLUT-1/VEGF expressions/pathologic tumor length (p-tumor length), and the relationships between pathologic T (p-T) stage and GLUT-1/VEGF expressions/SUV(max) and between lymph node metastasis (p-N) stage and GLUT-1/VEGF expressions/SUV(max).

RESULTS

SUV(max) significantly correlated with GLUT-1 expressions and p-tumor length (GLUT-1: r = 0.475, P < 0.001; p-tumor length: r = 0.475, P < 0.001). SUV(max) of the primary tumor had a significant relationship with p-T stage, p-N stage, and VEGF expression (p-T stage: P < 0.001; p-N stage: P = 0.037; VEGF expression: P = 0.009). There was a statistically significant difference between GLUT-1 expression and p-T stage/VEGF expression, but not p-N stage (p-T stage: P = 0.012; VEGF expression: P = 0.01; p-N stage: P = 0.572). VEGF expression had a significant relationship with p-T stage, but not with p-N stage (p-T stage: P = 0.032; p-N stage: P = 0.763).

CONCLUSION

(18)F-FDG uptake can be determined by GLUT-1 and VEGF. SUV(max) would have a connection with the tumor progression and lymph node metastasis.

Prognostic value of vascular endothelial growth factor expression in patients with esophageal cancer: a systematic review and meta-analysis

BACKGROUND

VEGF is a prime mediator of tumorigenesis and metastasis. Various studies assessing the prognostic value of VEGF in patients with esophageal cancer remain controversial. This study aims to comprehensively and quantitatively summarize the evidence on the suitability of VEGF to predict patients' survival.

METHODS

Searches were applied to PubMed and EMBASE until December 31, 2011, without language restrictions. Studies were assessed for quality using REMARK (Reporting recommendations for tumor MARKer prognostic studies). Data were collected comparing overall survival in patients with high VEGF level with those with low level. We conducted a systematic review of 31 studies (n = 2,387 patients) and completed a meta-analysis of 30 studies (n = 2,345 patients) that correlated VEGF levels with overall survival. Data were synthesized with HRs.

RESULTS

The estimated risk of death was 1.82-fold greater in patients with high VEGF expression [95% confidence interval (CI), 1.58-2.08]. The heterogeneity was not significant (P = 0.130) between studies. High VEGF expression was associated with worse survival in esophageal squamous cell carcinoma (HR, 1.81; 95% CI, 1.57-2.10) and there was no significance in between-study heterogeneity (P = 0.185). Data collected were not sufficient to determine the prognostic value of VEGF in patients with esophageal adenocarcinoma.

CONCLUSIONS

In this meta-analysis, elevated VEGF expression was associated with poor survival in patients with esophageal cancer but not esophageal adenocarcinoma.

IMPACT

These results support further investigation of VEGF expression for predicting poor survival in patients with esophageal carcinoma and may have implications for treatments directed at inhibiting VEGF-mediated angiogenesis.

The relationship between tumour necrosis, tumour proliferation, local and systemic inflammation, microvessel density and survival in patients undergoing potentially curative resection of oesophageal adenocarcinoma

Background:

There is increasing evidence that the local and systemic inflammatory responses are associated with survival in oesophageal cancer. The aim of this study was to examine the relationship between tumour necrosis, tumour proliferation, local and systemic inflammation and microvessel density and survival in patients undergoing potentially curative resection of oesophageal adenocarcinoma.

Methods:

The interrelationship between tumour necrosis, tumour proliferation, local inflammatory response (Klintrup–Makinen criteria, intra-tumoural CD8+ lymphocyte and macrophage infiltration), systemic inflammatory response (modified Glasgow Prognostic score (mGPS)), and microvessel density was examined in 121 patients undergoing potentially curative resection for oesophageal adenocarcinoma (including type I and II tumours of the gastro-oesophageal junction).

Results:

Tumour necrosis was not significantly associated with any tumour measure other than the degree of differentiation. On multivariate analysis, only age (HR 1.93, 95% CI 1.23–3.04, P=0.004), mGPS (HR 2.91, 95% CI 1.51–5.62, P=0.001), positive to total lymph node ratio (HR 2.38, 95% CI 1.60–3.52, P<0.001) and macrophage infiltration (HR 1.49, 95% CI 1.02–2.18, P=0.041) were independently associated with cancer-specific survival in oesophageal adenocarcinoma. Intra-tumoural macrophages were associated with tumour proliferation (P<0.001) and CD8+ lymphocytes infiltration (P<0.01).

Conclusion:

The results of this study suggest that tumour necrosis does not link local and systemic inflammatory responses and is not significantly associated with survival. In contrast, tumour macrophage infiltration appears to have a central role in the proliferative activity and the coordination of the inflammatory cell infiltrate and is independently associated with poorer survival in patients with oesophageal adenocarcinoma.

Hypoxia-induced radioresistance is independent of hypoxia-inducible factor-1A in vitro

PURPOSE

We sought to determine whether hypoxia-induced radioresistance is mediated by the transcription factor hypoxia-inducible factor-1alpha (HIF-1alpha).

METHODS AND MATERIALS

We used 2 mouse embryonic fibroblast cell lines transformed with H-ras and TAg, 1 HIF-1alpha+/+ and the other HIF-1alpha-/-. Cell were exposed to either 95% air and 5% CO2 (normoxic conditions) or 0.2% O2, 94.8% N2, and 5% CO2 (hypoxic conditions) for 4 hours. Cells were then irradiated and subjected to clonogenic survival assays.

RESULTS

Whereas neither +/+ ras/TAg nor -/- ras/TAg cells expressed HIF-1alpha under normoxic conditions, hypoxia induced expression of HIF-1alpha only in +/+ ras/TAg cells, confirming the absence of HIF-1alpha in -/- ras/TAg cells. Clonogenic survival curves for +/+ ras/TAg and -/- ras/TAg cells under normoxia and hypoxia demonstrated that hypoxia increased radioresistance in both cell lines to the same degree. At 1-log cell kill, the +/+ ras/TAg and -/- ras/TAg cells had an identical oxygen enhancement ratio of 1.28 +/- 0.09 and nearly identical oxygen enhancement ratios at 2-log cell kill.

CONCLUSION

In our system of transformed mouse embryonic fibroblasts, hypoxia-mediated radiation resistance is independent of HIF-1alpha.