David Borg

Pancreatic cancer : Yesterday, today and tomorrow

Pancreatic cancer is one of our most lethal malignancies. Despite substantial improvements in the survival rates for other major cancer forms, pancreatic cancer survival rates have remained relatively unchanged since the 1960s. Pancreatic cancer is usually detected at an advanced stage and most treatment regimens are ineffective, contributing to the poor overall prognosis. Herein, we review the current understanding of pancreatic cancer, focusing on central aspects of disease management from radiology, surgery and pathology to oncology.

Experiences from treatment-predictive KRAS testing; high mutation frequency in rectal cancers from females and concurrent mutations in the same tumor

BackgroundKRAS mutations represent key alterations in colorectal cancer development and lead to constitutive EGFR signaling. Since EGFR inhibition represents a therapeutic strategy in advanced colorectal cancer, KRAS mutation analysis has quickly been introduced as a treatment-predictive test.MethodsWe used a real-time PCR based method to determine KRAS mutations in 136 colorectal cancers with mutations identified in 53 (39%) tumors.ResultsKRAS mutations were significantly more often found in rectal cancer (21/38, 55%) than in colon cancer (32/98, 33%) (P = 0.02). This finding was explained by marked differences mutation rates in female patients who showed mutations in 33% of the colon cancers and in 67% of the rectal cancers (P = 0.01). Concurrent KRAS mutations were identified in three tumors; two colorectal cancers harbored Gly12Asp/Gly13Asp and Gly12Cys/Gly13Asp and a third tumor carried Gly12Cys/Gly12Asp in an adenomatous component and additionally acquired Gly12Val in the invasive component.ConclusionThe demonstration of a particularly high KRAS mutation frequency among female rectal cancer patients suggests that this subset is the least likely to respond to anti-EGFR therapies, whereas the observation of concurrent KRAS mutations imply that repeated KRAS targeting may occur during tumor progression in a subset of colorectal cancers.

Discordant HER2 overexpression in primary and metastatic upper gastrointestinal adenocarcinoma signifies poor prognosis.

Targeted therapy with trastuzumab has proved to be effective for patients with gastric cancer overexpressing the human epidermal growth factor receptor 2 (HER2). Further studies are needed to determine the best method for assessment of HER2 overexpression. Moreover, the prognostic value of HER2 overexpression, including the significance of tumour heterogeneity, remains unclear.

Expression and Prognostic Significance of Human Epidermal Growth Factor Receptors 1 and 3 in Gastric and Esophageal Adenocarcinoma

Background Gastric and esophageal adenocarcinomas are major global cancer burdens. These cancer forms are characterized by a poor prognosis and a modest response to chemo- radio- and targeted treatment. Hence there is an obvious need for further enhanced diagnostic and treatment strategies. The aim of this study was to examine the expression and prognostic impact of human epidermal growth factor receptor 1 (HER1/EGFR) and 3 (HER3), as well as the occurrence of EGFR and KRAS mutations in gastric and esophageal adenocarcinoma. Methods Immunohistochemical expression of EGFR and HER3 was analysed in all primary tumours and a subset of lymph node metastases in a consecutive cohort of 174 patients with adenocarcinoma of the stomach, cardia and esophagus. The anti-HER3 antibody used was validated by siRNA-mediated knockdown, immunohistochemistry and quantitative real-time PCR. EGFR and KRAS mutation status was analysed by pyrosequencing tecchnology. Results and Discussion High EGFR expression was an independent risk factor for shorter overall survival (OS), whereas high HER3 expression was associated with a borderline significant trend towards a longer OS. KRAS mutations were present in only 4% of the tumours and had no prognostic impact. All tumours were EGFR wild-type. These findings contribute to the ongoing efforts to decide on the potential clinical value of different HERs and druggable mutations in gastric and esophageal adenocarcinomas, and attention is drawn to the need for more standardised investigational methods.

Prognostic impact of tumour-associated B cells and plasma cells in oesophageal and gastric adenocarcinoma

BACKGROUND While it is well established that the cell-mediated immune response plays an important role in cancer progression and spread, the role of the humoral immune response in this regard has been less studied. According to the existing literature, dense infiltration of B cells or plasma cells appears to correlate mainly with an improved prognosis in several types of cancer, but their prognostic impact in oesophageal and gastric cancer has not yet been described. METHODS Immunohistochemistry was applied on tissue microarrays (TMA) to assess the stromal density of B cells (CD20+) and plasma cells [CD138+ or immunoglobulin kappa C (IGKC+)] in chemo-/radiotherapy-naive tumours from a consecutive cohort of 174 patients with resected oesophageal or gastric adenocarcinoma. Cox proportional hazards modelling was applied to examine the impact of the investigated markers on overall survival (OS) and time to recurrence (TTR). RESULTS In curatively treated patients with oesophageal adenocarcinoma, high expression of IGKC was an independent predictor of a prolonged OS [hazard ratio (HR) 0.10; 95% confidence interval (CI), 0.02-0.57], and TTR (HR 0.15; 95% CI, 0.03-0.71). In curatively treated patients with gastric adenocarcinoma, high expression of IGKC independently predicted a prolonged OS (HR 0.46; 95% CI, 0.24-0.87) and TTR (HR 0.46; 95% CI, 0.21-0.98). Expression of CD20 was not prognostic, and CD138 expression was only prognostic in unadjusted analysis of TTR in gastric cancer. CONCLUSIONS These results demonstrate, for the first time, that abundant infiltration of IGKC+ plasma cells independently predicts a prolonged survival in both oesophageal and gastric cancer.

The integrative clinical impact of tumor-infiltrating T lymphocytes and NK cells in relation to B lymphocyte and plasma cell density in esophageal and gastric adenocarcinoma

Background Several studies have demonstrated a prognostic impact of tumor-infiltrating T lymphocytes and natural killer (NK) cells in esophageal and gastric adenocarcinoma, but whether these associations differ by the density of tumor-infiltrating immune cells of the B cell lineage remains largely unknown. Results High infiltration of any T and NK lymphocytes investigated was in general associated with a favorable prognosis, but the strongest beneficial prognostic impact was seen in combination with high B lymphocyte infiltration. These findings were most evident in gastric cancer, where significant interactions in relation to OS were observed for CD3+, CD8+ and FoxP3+ with CD20+ cells (pinteraction =0.012, 0.009 and 0.007, respectively) and for FoxP3+ with IGKC+ cells (pinteraction =0.034). In esophageal tumors, there was only a significant interaction for CD3+ and CD20 + cells (pinteraction =0.028). Methods Immunohistochemistry and automated image analysis was applied to assess the density of T lymphocytes (CD3+, CD8+, FoxP3+) and NK cells (NKp46+) in chemoradiotherapy-naïve tumors from a consecutive cohort of 174 patients with resected esophageal or gastric adenocarcinoma. The density of B lymphocytes (CD20+) and plasma cells (IGKC+) had been assessed previously. Kaplan-Meier analysis and Cox proportional hazards modelling was applied to examine the impact of the investigated markers on time to recurrence (TTR) and overall survival (OS). Conclusions These data support that the antitumoral effects of tumor-infiltrating T lymphocytes in esophageal and gastric adenocarcinoma may be largely dependent on a functional interplay between T and B lymphocytes or plasma cells.BACKGROUND Several studies have demonstrated a prognostic impact of tumor-infiltrating T lymphocytes and natural killer (NK) cells in esophageal and gastric adenocarcinoma, but whether these associations differ by the density of tumor-infiltrating immune cells of the B cell lineage remains largely unknown. RESULTS High infiltration of any T and NK lymphocytes investigated was in general associated with a favorable prognosis, but the strongest beneficial prognostic impact was seen in combination with high B lymphocyte infiltration. These findings were most evident in gastric cancer, where significant interactions in relation to OS were observed for CD3+, CD8+ and FoxP3+ with CD20+ cells (pinteraction =0.012, 0.009 and 0.007, respectively) and for FoxP3+ with IGKC+ cells (pinteraction =0.034). In esophageal tumors, there was only a significant interaction for CD3+ and CD20 + cells (pinteraction =0.028). METHODS Immunohistochemistry and automated image analysis was applied to assess the density of T lymphocytes (CD3+, CD8+, FoxP3+) and NK cells (NKp46+) in chemoradiotherapy-naïve tumors from a consecutive cohort of 174 patients with resected esophageal or gastric adenocarcinoma. The density of B lymphocytes (CD20+) and plasma cells (IGKC+) had been assessed previously. Kaplan-Meier analysis and Cox proportional hazards modelling was applied to examine the impact of the investigated markers on time to recurrence (TTR) and overall survival (OS). CONCLUSIONS These data support that the antitumoral effects of tumor-infiltrating T lymphocytes in esophageal and gastric adenocarcinoma may be largely dependent on a functional interplay between T and B lymphocytes or plasma cells.

Expression and prognostic significance of human epidermal growth factor receptors 1, 2 and 3 in oesophageal and gastric adenocarcinomas preneoadjuvant and postneoadjuvant treatment

Aims Neoadjuvant treatment has now become the standard of care for oesophageal and gastric cancer. The aim of this study was to investigate the influence of neoadjuvant therapy on the expression of human epidermal growth factor receptor 1 (HER1/EGFR), HER2 and HER3, in oesophageal and gastric adenocarcinoma. Methods Immunohistochemical expression of EGFR, HER2 and HER3 was examined and compared in pretreatment biopsies, post-treatment surgical resection specimens and metastases in a retrospective cohort of 166 patients with adenocarcinoma of the oesophagus or stomach. The relationship between expression of the investigative markers and histopathological response to neoadjuvant treatment, overall survival (OS) and recurrence free survival (RFS) was analysed. Results Conversion of protein expression between pretreatment biopsy and post-treatment surgical resection was seen in 4.6% of the cases for EGFR, 5.9% for HER2% and 19.4% for HER3. Histopathological response to neoadjuvant treatment was significantly and stepwise associated with OS and RFS . High HER3 protein expression in post-treatment surgical resection specimens was significantly associated with a prolonged OS in univariable analysis (HR=0.39; 95% CI 0.17 to 0.93), but did not remain significant in multivariable analysis. Expression of EGFR and HER2 in post-treatment surgical resection specimens was not prognostic. No correlation between pretreatment HER-protein expression and histopathological response was seen. Conclusions The results from this study underscore the need for further studies on the influence of neoadjuvant treatment on biomarker expression, as this may influence treatment strategy as well as prognosis. Histopathological response is validated as a useful prognostic factor.