There is a pending need for prognostic and predictive biomarkers in the treatment of patients with colorectal cancer.This thesis describes the prognostic and predictive application of the tumor... Show moreThere is a pending need for prognostic and predictive biomarkers in the treatment of patients with colorectal cancer.This thesis describes the prognostic and predictive application of the tumor-stroma ratio (TSR) in colorectal cancer, focusing on expanding current clinical-pathological standards and combining TSR with other diagnostic parameters. The TSR is a microscopy scoring method performed on hematoxylin-eosin stained tissue slides used for routine pathology assessment, and has proven to be a robust prognostic maker. Here, we investigate whether the TSR also exhibits predictive value with regard to adjuvant targeted therapy in stage II and III colon cancer. Moreover, exploring the value of collagen fiber organization in the intratumoral stroma, as well as combining this parameter with the TSR. Finally, expanding the application of the TSR with radiological diagnostics in rectal cancer. Assessing is there is a correlation between TSR and apparent diffusion coefficient values obtained from diagnostically performed MRI-DWI scans, in order to determine if there is potential with regards to neoadjuvant treatment choices or patient follow-up. Show less
Objective: This study evaluated the correlation between intratumoural stmma proportion, expressed as tumour-stroma ratio (TSR), and apparent diffusion coefficient (ADC) values in patients with... Show moreObjective: This study evaluated the correlation between intratumoural stmma proportion, expressed as tumour-stroma ratio (TSR), and apparent diffusion coefficient (ADC) values in patients with rectal cancer.Methods: This multicentre retrospective study included all consecutive patients with rectal cancer, diagnostically confirmed by biopsy and MRI. The training cohort (LUMC, Netherlands) included 33 patients and the validation cohort (VHIO, Spain) 69 patients. Two observers measured the mean and minimum ADCs based on single-slice and whole-volume segmentations. The TSR was determined on diagnostic haematoxylin & eosin stained slides of rectal tumour biopsies. The correlation between TSR and ADC was assessed by Spearman correlation (r(s)).Results: The ADC values between stroma-low and stroma-high tumours were not significantly different. Intraclass correlation (ICC) demonstrated a good level of agreement for the ADC measurements, ranging from 0.84-0.86 for single slice and 0.86-0.90 for the whole-volume protocol. No correlation was observed between the TSR and ADC values, with ADC(mean), r(s) = -0.162 (p= 0.38) and ADC(m)(in), r(s) = 0.041 (p= 0.82) for the single-slice and r(s) = -0.108 (p= 0.55) and r(s) = 0.019 (p= 0.92) for the whole-volume measurements in the training cohort, respectively. Results from the validation cohort were consistent; ADC(mean )r(s) = -0.022 (p= 0.86) and ADC(min), r(s) = 0.049 (p= 0.69) for the single-slice and r(s) = -0.064 (p= 0.59) and r(s) = -0.063 (p= 0.61) for the whole-volume measurements.Conclusions: Reproducibility of ADC values is good. Despite positive reports on the correlation between TSR and ADC values in other tumours, this could not be confirmed for rectal cancer. Show less
It has become clear that carcinogenesis goes beyond tumor cell biology. Cancer research has acknowledged the importance of biological functions of the tumor-microenvironment, wherein not only... Show moreIt has become clear that carcinogenesis goes beyond tumor cell biology. Cancer research has acknowledged the importance of biological functions of the tumor-microenvironment, wherein not only cellular components seem to hold valuable information but also structural components like collagen fibers. Several studies have focused on the significance of stromal collagen fiber organization and reported on its role in cancer progression, invasiveness and treatment response. In this review, we discuss the different imaging methods for stromal collagen organization, followed by an in-depth discussion of current literature on in-vitro and animal experiments and human studies, highlighting its importance with respect to cancer progression, prognosis and prediction. We can conclude that collagen organization contains valuable information with regard to metastatic potential and clinical outcomes in cancer. However, the significance of an aligned versus disorganized collagen morphology differs between cancer types, implying more research is necessary before steps towards clinical implementation can be made. Show less
Background: Tumor-stroma ratio (TSR) is an independent prognosticator in colon cancer.Objective: We set out to investigate the predictive power, as well as to validate the prognostic power of TSR... Show moreBackground: Tumor-stroma ratio (TSR) is an independent prognosticator in colon cancer.Objective: We set out to investigate the predictive power, as well as to validate the prognostic power of TSR in stage II colon cancer patients. Better identification of patients who could benefit from adjuvant chemotherapy remains an important issue in stage II disease.Methods: TSR was microscopically determined on haematoxylin and eosin-stained primary tumor tissue slides of 212 patients who received either adjuvant chemotherapy or surveillance after curative resection in a prospective randomized clinical trial (ABCSG-91).Results: Stroma-high tumors were associated with significantly more cancer-related death ((CaDeath) HR 2.30, 95% CI 1.05−5.03; p=0.037) and significantly shorter distant recurrence-free survival ((DRFS) HR 2.32, 95% CI 1.10−4.87; p=0.027) compared to stroma-low tumors. Backward multivariate Cox-regression analysis demonstrated TSR as an independent prognosticator for DRFS (p=0.027) and CaDeath (p=0.031). TSR did not validate as a predictive biomarker; CaDeath (HR 0.87, 95% CI 0.18−4.17; p=0.87), DRFS (HR 0.76, 95% CI 0.17−3.36; p=0.71) and OS (HR 0.96, 95% CI 0.29−3.21; p=0.95) for the type of chemotherapy given in ABCSG-91.Conclusions: TSR, an easily applicable and inexpensive observer-based method, is an independent predictor of poor prognosis in stage II colon cancer. Predictive value for adjuvant 5-FU/leucovorin could not be demonstrated. Show less
It has become clear that carcinogenesis goes beyond tumor cell biology. Cancer research has acknowledged the importance of biological functions of the tumor-microenvironment, wherein not only... Show moreIt has become clear that carcinogenesis goes beyond tumor cell biology. Cancer research has acknowledged the importance of biological functions of the tumor-microenvironment, wherein not only cellular components seem to hold valuable information but also structural components like collagen fibers. Several studies have focused on the significance of stromal collagen fiber organization and reported on its role in cancer progression, invasiveness and treatment response. In this review, we discuss the different imaging methods for stromal collagen organization, followed by an in-depth discussion of current literature on in-vitro and animal experiments and human studies, highlighting its importance with respect to cancer progression, prognosis and prediction. We can conclude that collagen organization contains valuable information with regard to metastatic potential and clinical outcomes in cancer. However, the significance of an aligned versus disorganized collagen morphology differs between cancer types, implying more research is necessary before steps towards clinical implementation can be made. Show less
