Total circulating cell-free DNA as a prognostic biomarker in metastatic colorectal cancer before first-line oxaliplatin-based chemotherapy.

BACKGROUND: Metastatic colorectal cancer (mCRC) is a heterogeneous disease where prognosis is dependent both on tumor biology and host factors. Total circulating cell-free DNA (cfDNA) has shown to harbor prognostic information in mCRC, although less is known about the biological correlates of cfDNA levels in this patient group. The primary objective was to evaluate the prognostic value of pretreatment cfDNA in patients receiving the first-line oxaliplatin-based chemotherapy for mCRC, by using a predefined upper limit of normal (ULN) from a cohort of presumed healthy individuals. The secondary objective was to model cfDNA levels as a function of predefined tumor and host factors. PATIENTS AND METHODS: This was a retrospective post hoc study based on a prospective multicenter phase III trial, the NORDIC-VII study. DNA was purified from 547 plasma samples and cfDNA quantified by a droplet digital PCR assay (B2M, PPIA) with controls for lymphocyte contamination. Main clinical end point was overall survival (OS). RESULTS: cfDNA was quantified in 493 patients, 54 were excluded mainly due to lymphocyte contamination. Median cfDNA level was 7673 alleles/ml (1050-1 645 000) for B2M and 5959 alleles/ml (555-854 167) for PPIA. High cfDNA levels were associated with impaired outcome; median OS of 16.6 months for levels above ULN and 25.9 months for levels below ULN (hazard ratio = 1.83, 95% confidence interval 1.51-2.21, P < 0.001). The result was confirmed in multivariate OS analysis adjusting for established clinicopathological characteristics. A linear regression model predicted cfDNA levels from sum of longest tumor diameters by RECIST, the presence of liver metastases and systemic inflammatory response as measured by interleukin 6 (F(6, 357) = 62.7, P < 0.001). CONCLUSION: cfDNA holds promise as a minimally invasive and clinically relevant prognostic biomarker in mCRC before initiating first-line oxaliplatin-based chemotherapy and may be a complex entity associated with tumor burden, liver metastases and systemic inflammatory response. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00145314.

AGXT and ERCC2 polymorphisms are associated with clinical outcome in metastatic colorectal cancer patients treated with 5-FU/oxaliplatin.

The objective of the study was to investigate whether specific single nucleotide polymorphisms (SNPs) with influence on drug transport, biotransformation and repair mechanisms are associated with treatment outcome and toxicity in metastatic colorectal cancer (mCRC). We genotyped blood samples from 519 mCRC patients treated with first-line 5-fluorouracil and oxaliplatin +/- cetuximab for 17 SNPs in 10 genes involved in membrane transport (ABCC1 and ABCC2), drug biotransformation (GSTP1 and AGXT) and DNA repair (ERCC1, ERCC2, XRCC1, XRCC3, XPG and MSH6). The AGXT-rs34116584 and the ERCC2-rs238406 polymorphisms were significantly associated with progression-free survival (P=0.002 and P=0.001, respectively). Associations between 18 toxicity variables and SNPs were identified, although none were significant after Bonferroni correction for multiple comparisons. The study identified SNPs of potential use as markers of clinical outcome in oxaliplatin-treated mCRC patients. If validated in other studies, they could improve the selection of therapy in mCRC.

Expression of cyclin D1a and D1b as predictive factors for treatment response in colorectal cancer.

BACKGROUND: The aim of this study was to investigate the value of the cyclin D1 isoforms D1a and D1b as prognostic factors and their relevance as predictors of response to adjuvant chemotherapy with 5-fluorouracil and levamisole (5-FU/LEV) in colorectal cancer (CRC). METHODS: Protein expression of nuclear cyclin D1a and D1b was assessed by immunohistochemistry in 335 CRC patients treated with surgery alone or with adjuvant therapy using 5-FU/LEV. The prognostic and predictive value of these two molecular markers and clinicopathological factors were evaluated statistically in univariate and multivariate survival analyses. RESULTS: Neither cyclin D1a nor D1b showed any prognostic value in CRC or colon cancer patients. However, high cyclin D1a predicted benefit from adjuvant therapy measured in 5-year relapse-free survival (RFS) and CRC-specific survival (CSS) compared to surgery alone in colon cancer (P=0.012 and P=0.038, respectively) and especially in colon cancer stage III patients (P=0.005 and P=0.019, respectively) in univariate analyses. An interaction between treatment group and cyclin D1a could be shown for RFS (P=0.004) and CSS (P=0.025) in multivariate analysis. CONCLUSION: Our study identifies high cyclin D1a protein expression as a positive predictive factor for the benefit of adjuvant 5-FU/LEV treatment in colon cancer, particularly in stage III colon cancer.

Expression of EZH2 and Ki-67 in colorectal cancer and associations with treatment response and prognosis.

BACKGROUND: Enhancer of zeste homologue 2 (EZH2) is a member of the Polycomb group of genes that is involved in epigenetic silencing and cell cycle regulation. METHODS: We studied EZH2 expression in 409 patients with colorectal cancer stages II and III. The patients were included in a randomised study, and treated with surgery alone or surgery followed by adjuvant chemotherapy. RESULTS: EZH2 expression was significantly related to increased tumour cell proliferation, as assessed by Ki-67 expression. In colon cancer, strong EZH2 expression (P=0.041) and high proliferation (>or=40%; P=0.001) were both associated with better relapse-free survival (RFS). In contrast, no such associations were found among rectal cancers. High Ki-67 staining was associated with improved RFS in colon cancer patients who received adjuvant chemotherapy (P=0.001), but not among those who were treated by surgery alone (P=0.087). In colon cancers stage III, a significant association between RFS and randomisation group was found in patients with high proliferation (P=0.046), but not in patients with low proliferation (P=0.26). Multivariate analyses of colon cancers showed that stage III (hazard ratio (HR) 4.00) and high histological grade (HR 1.80) were independent predictors of reduced RFS, whereas high proliferation indicated improved RFS (HR 0.55). CONCLUSION: Strong EZH2 expression and high proliferation are associated features and both indicate improved RFS in colon cancer, but not so in rectal cancer.

Human embryonal carcinoma grown in athymic mice and in vitro.

Tissue from 19 human testis tumors was transplanted into athymic mice. One embryonal carcinoma, ECCS, grew rapidly, and this tumor was studied both as a xenograft and an in vitro culture of xenograft-derived tumor cells. Xenografts showed no evidence of differentiation. The embryonal carcinoma cells were heteroploid and showed alkaline phosphatase activity. When tumor cells from the xenografts were grown in vitro, the cells formed aggregates resembling embryoid bodies with epithelium-like cells in the periphery. Regularly, another population of mouse cells which showed several criteria of malignancy overgrew the culture and could be subcultured continuously. These abnormal cells may result from an in vivo or in vitro transformation of mouse stromal cells.

Quality of life and functional outcome following anterior or abdominoperineal resection for rectal cancer.

AIMS: The aims of the study were (1) to evaluate quality of life (QoL) and functional outcome in patients following anterior resection (AR) or abdominoperineal resection (APR) for rectal cancer, and (2) whether these outcomes were dependent on the level of anastomosis. METHODS: Patients who were without recurrent or metastatic disease were identified from the Norwegian Rectal Cancer Registry. QoL was assessed by the EORTC questionnaires QLQ-C30 and QLQ-CR38, and rectal function by a short questionnaire. Of 319 patients studied, 229 had undergone AR and 90 APR. The median age was 73 years, and the median time since surgery was 64 months. RESULTS: Mean QoL scores for body image and male sexual problems were better following AR than APR (P<0.01), also in patients with a low (< or = 3 cm) anastomosis. Patients who had undergone AR had higher mean scores for constipation (P<0.001) and more often used anti-diarrhoeal medication (P=0.005), than patients who had undergone APR. Patients with a low anastomosis (< or = 3 cm) had more incontinence for gas and solid stools (P<0.05), and had more incontinence (P=0.006) compared with patients with higher anastomosis, but there was no difference in QoL. Subgroup analysis showed that irradiated patients (n=34) had worse rectal function in terms of frequency, urgency, and incontinence (P<0.01). CONCLUSIONS: Although rectal function was impaired in patients with low anastomosis, patients who had undergone AR had better QoL than patients who had undergone APR.

Changes in folate status as determined by reduction in total plasma homocysteine levels during leucovorin modulation of 5-fluorouracil therapy in cancer patients.

We measured plasma total homocysteine (tHcy) in 14 patients (13 patients with colorectal cancer and 1 patient with breast cancer) during their first treatment with 5-fluorouracil (5-FU) plus leucovorin [LV (5-FULV)]. Eight of these patients were investigated a second time after 3-10 cycles (median, 4 cycles) with 5-FULV. Each cycle consisted of two administrations of 5-FU (500 mg/m2) and LV (60 mg/m2) given 24 h apart. The first administration of 5-FULV on day 1 of the first cycle induced a rapid reduction of the tHcy level from 12.5 micromol/liter (10.4-15.1 micromol/liter; geometric mean with 95% confidence interval of the mean) to 9.1 micromol/liter (7.5-11.1 micromol/liter) in 24 h. tHcy remained stable at this level after the second administration of 5-FULV. In addition, the 5-FULV regimen caused a concurrent 4-fold increase in both serum and erythrocyte folate. The fifth cycle with 5-FULV had only marginal effects on the tHcy level. 5-FU without LV modulation had no effect on the plasma tHcy or folate status in eight breast cancer patients. Our data establish the reduction of tHcy as a responsive indicator of LV pharmacodynamics.

Intra-operative irradiation (IORT) for primary advanced and recurrent rectal cancer. a need for randomised studies.

The aim of this study was to determine the impact of intra-operative irradiation (IORT) combined with pre-operative external beam irradiation (EBRT) and surgical resection in patients with locally advanced primary or recurrent rectal cancer. 64 patients with locally advanced primary cancer and 104 with recurrence had EBRT (46-50 Gy) before surgery. 80 patients received IORT (median dose 15 Gy energy 12 MeV). 80 patients had R0 resections, 47 R1 and 41 R2 resections. More R1 resections were performed in the IORT group, more R0 and R2 resections in the non-IORT group. Median follow-up was around 22 months. 146 patients were resected, 22 had exploratory laparotomy. The cumulative overall survival was similar for both the IORT and non-IORT groups. 5-year survival for primary cancers was 48% versus 28% for recurrences. No R2 resections survived 3.5 years. 5-year-survival for R0 resections was nearly 60% and around 30% for R1 resections. The survival curves of the patients given and not given IORT treatment was not statistically different when R0, R1 and R2 resections were analysed separately. IORT did not seem to influence the local recurrence rate when R0 and R1 resections were analysed separately or in a multivariate analysis. The IORT and non-IORT groups were not identical with regard to type of cancer and R-stage. Still the lack of an identifiable impact of IORT suggests that there is a need for randomised studies of the IORT effect.

Quality of life during radiotherapy for rectal cancer.

The aim of this study was to assess symptoms and health-related quality of life (HRQL) during (neo)adjuvant radiotherapy for rectal cancer. Patients receiving pelvic radiotherapy 50 Gy for rectal cancer, were studied prospectively (n=42). The European Organization for Research and Treatment of Cancer (EORTC) questionnaires quality of life-core 30 QLQ-C30 and QLQ-CR38 and a 5-day symptom diary were completed at the start and end of radiotherapy and 4-6 weeks later. At the end of radiotherapy, mean scores of diarrhoea, fatigue and appetite loss had significantly increased (P<0.01) compared with pretreatment scores, but this was not observed for scores for nausea or pain. At the end of radiotherapy, diarrhoea, fatigue, appetite loss, physical function, social function and global quality of life (QL) were significantly worse than the population-based norms. 64% of the patients reported an increase in fatigue and 52% an increase in diarrhoea during radiotherapy. HRQL scores had returned to pre-treatment levels 4-6 weeks after radiotherapy. Thus, diarrhoea, fatigue and appetite loss increased transiently during pelvic radiotherapy.

Survival curves after X-ray and heat treatments for melanoma cells derived directly from surgical specimens of tumours in man.

X-ray and heat survival curves were established for melanoma cells derived directly from surgical specimens of tumours in man by using the Courtenay soft agar colony assay. The plating efficiency for 11 of the 14 melanomas studied was sufficiently high (PE = 0.3-58%) to measure cell survival over at least two decades. Experiments repeated with cells stored in liquid nitrogen showed that the survival assay gave highly reproducible results. The melanomas exhibited individual and characteristic survival curves whether exposed to radiation or heat (43.5 degrees C). The Do-values were in the ranges 0.63-1.66 Gy (X-rays) and 33-58 min (heat). The survival curves were similar to those reported previously for human melanoma xenografts. The radiation sensitivity of the cells was not correlated to the heat sensitivity. Since the melanomas appeared to be very heterogeneous in radiation response in vitro as melanomas are known to be clinically, it is suggested that melanomas may be suitable for prospective studies aimed at establishing whether clinical radioresponsiveness somehow is related to in vitro survival curve parameters.

Combined modality treatment including intraoperative radiotherapy in locally advanced and recurrent rectal cancer.

BACKGROUND: Treatment of locally advanced and recurrent rectal cancer usually has a high local recurrence rate and poor survival. Promising results have been reported by combined external radiotherapy, extensive surgery and intraoperative radiotherapy (IORT). METHODS: One hundred fifteen patients with locally advanced rectal cancers fixed to the pelvic wall or locally recurrent rectal cancers underwent preoperative external radiotherapy with 46-50 Gy. Six to 8 weeks later radical pelvic surgery was attempted, and was combined with intraoperative electron beam radiotherapy (15-20 Gy) in 66 patients. The patients were followed closely to evaluate complication rate, local and distant recurrence rate and survival. RESULTS: Surgery with no macroscopic tumour remaining was obtained in 65% of the patients with no postoperative deaths. Pelvic infection was the major complication (21%). Although the observation time is short (3-60 months), the local recurrence rate seems low (22%) and survival seems promising (about 60% at 4 years) in patients with complete tumour resection, in contrast to patients with residual tumour (none living at 4 years). CONCLUSIONS: The combined modality treatment with preoperative external radiotherapy and extensive pelvic surgery with IORT is sufficiently promising to start a randomized trial on the clinical value of IORT as a boost treatment in the multidisciplinary approach to this disease.

An immunocytochemical method for assaying oestrogen receptors in breast cancers. A comparison with the steroid binding assay.

The presence of oestrogen receptors was studied in 105 human breast carcinomas using monoclonal antibodies (Abbott ER-ICA kit). The oestrogen receptors of neoplastic cells were semiquantitatively measured and correlations were made to receptor values determined by a dextran-coated charcoal (DCC) steroid binding assay and to histological grade. Immunoreactive cells were found in about 2/3 of the tumours. Usually only a fraction of the cells within each tumour were immunoreactive, and the staining intensity varied among different cells. In general, well differentiated tumours had a greater proportion of immunoreactive cells than poorly differentiated ones. In most cases (65/98) a good agreement was found between the ER-ICA method and the DCC assay. However, in 33 cases discrepancies were demonstrated.

Location of pelvic recurrence after 'curative' low anterior resection for rectal cancer.

AIMS: It has been emphasized that the mesorectum is the key to local recurrence after resection for rectal cancer. In view of this we studied the location of recurrences, relative to the bed of the primary tumour, the neorectum and the level of anastomoses, in patients referred for recurrences after low anterior resection (LAR) in the <>. METHODS: The relative level above the anal verge of the primary cancer, the anastomosis and the recurrence was registered by proctoscopy in 46 patients operated on for recurrent cancer after low anterior resection. The origin of the recurrence was determined from the operative specimen. RESULTS: The median level of the primary cancers was 10 cm above the anal verge, with the anastomoses 2 cm lower, the majority being within 2 cm. Most recurrences were within 1 cm of the anastomosis. No rectal cancer occurred more than 3 cm distal to the anastomosis. Seventy to 80% of recurrences started peri-rectally, most invading the anastomosis. CONCLUSIONS: The tumour bed is most often the origin of the recurrence. Recurrences were mostly due to inadequate radial, and in a few cases longitudinal, dissection of the mesorectum. Virtually all recurrences were within reach of the examining finger. At follow-up of rectal cancers most local recurrences can therefore be identified earlier by digital examination than by proctoscopy.

Quality of life in patients with urinary diversion after operation for locally advanced rectal cancer.

AIMS: When locally advanced or recurrent rectal cancer involves the bladder or prostate, curative treatment often requires pelvic exenteration. The aim was to assess the quality of life (QoL) in disease-free patients with urinary diversion after extensive surgery for advanced rectal cancer. METHODS: Twelve patients with urinary diversion (cases) were compared with 25 randomly selected patients given the same treatment, but without urinary diversion (controls). An age- and gender-adjusted general population was identified (reference). QoL was assessed with the EORTC questionnaires QLQ-C30, QLQ-CR38, and parts of the QLQ-BLM30. RESULTS: The cases did not report significantly worse overall QoL than the controls or the reference population. Both cases and controls had low mean scores of sexual function, and high mean scores of male sexual problems. In the nine cases that had two stomas, overall QoL was not worse than in the control or reference groups. CONCLUSIONS: Tumour-free patients did not report worse QoL scores than the controls or the general population, despite most having two stomas and low sexual function. Fear of reducing the patient's QoL should not be a major contraindication when surgery with urinary diversion is warranted to obtain curative resection.

Colony formation in urinary bladder carcinoma. Relationship to DNA flow cytometry, stage and histopathology.

Tumour cells from 74 biopsies from human urinary bladder carcinomas were cultivated in a semisolid system (Courtenay and Mills method). In 51 cases DNA flow cytometry (FCM) was performed. Significant growth was obtained in 53 of 74 cases (71.6%), and good quality DNA histograms from FCM were obtained in all 51 attempts. No correlations between clinical or histopathological data and plating efficiency (PE) were found, nor between ploidy and PE. However, a very high S-phase (greater than 15%) correlated with a low PE. This work shows that bladder carcinoma cells can be studied in a semisolid agar system. It also suggests that there exists no correlation between PE and DNA FCM data or clinical or histopathological data.

Colony-forming ability of human ovarian carcinomas in the Courtenay soft agar assay.

One hundred and twenty-one ovarian carcinomas were cultivated in soft agar according to the Courtenay & Mills (C-M) soft agar method. 71% of the tumours formed colonies, and 54% formed more than 30 colonies. Tumour cells from malignant fluids grew more frequently than did solid tumours, whereas the plating efficiencies (PEs) were higher in the case of solid tumours. In general, the PEs were higher and more tumours formed colonies in the C-M method compared to the Hamburger-Salmon (H-S) method. The colony-forming ability did not show statistically significant correlation to histopathological type and grade, previous treatment and S-phase fraction, but was related to DNA ploidy. In poorly differentiated tumours a high colony-forming ability was associated with a poor prognosis, whereas the opposite was found in well and moderately differentiated tumours. Differential dose-response relationships were obtained after in vitro treatment with anticancer agents.

Benzylidene-glucose: no effect after all?

Several promising reports on the treatment of human cancer with various benzaldehyde derivatives have been published during the last decade. The present phase II study was performed to investigate whether the rather sensational results of one such derivative, benzylidene-D-glucose (BG), could be confirmed. The study included 14 patients with metastases from adenocarcinomas of the colon and rectum. The patients were treated with BG according to the recommended regimen for 8 weeks, after which tumor response was evaluated. Neither clinical tumor regression nor side effects were observed. The present study does not confirm the extremely good results previously reported by others. We conclude that BG is not an active agent in colorectal cancer.

Flow cytometric DNA analysis as prognostic factor in human breast carcinoma.

Fresh tumour tissue from 198 primary invasive breast carcinomas was analysed by DNA flow cytometry. 108 tumours were non-diploid. A significantly higher proportion of non-diploid tumours was found among node-positive patients, patients with oestrogen receptor negative tumours and among patients with ductal carcinomas. The survival of patients with diploid and non-diploid tumours was not significantly different (p = 0.1). Totally, 145 tumours were analyzed with respect to S-phase fraction (SPF). The distribution of SPF was different in diploid and non-diploid tumours. A low SPF group, defined as the lower SPF quartile (< or = 4.6% in diploid and < or = 8.5% in non-diploid tumours), was associated with highly differentiated tumours and oestrogen receptor positive tumours. Histological grading revealed a highly significant correlation to SPF. 57% of ductal carcinomas grade I (8 out of 14), 30% of ductal carcinomas grade II (20 out of 67) and 5% of ductal carcinomas grade III (2 out of 37) had a low SPF. Patients within the low SPF group had a significantly longer survival than had patients within the high SPF group (p = 0.006). In a multivariate analysis the SPF was found to be an additional prognostic factor next to node status and ER status.

Field homogeneity of bevelled intraoperative electron beam cones: the influence of virtual focus surface distance.

Field flatness of bevelled intraoperative electron therapy cones were evaluated from dose profiles, taken at dmax, both in the longitudinal plane (long axis direction) and the transversal plane (short axis direction), and were found to depend strongly on the setting of the x-ray collimators. Dose gradients in the longitudinal plane of 10-12% were found for collimator settings of 5 mm larger than the cone diameter for low energies, while the dose gradient were smaller for higher energies, both decreasing with larger collimator setting. The dose increase, relative to the central dose, of the hot spots observed in the profile of the transversal plane were in the range of 5-10% for high energies and large collimator settings, decreasing to less than 3% for low electron beam energies and smaller collimator setting. A decrease in virtual focus to surface distance (VFSD) was found to accompany the increasing dose gradient in the longitudinal plane with decreasing collimator setting, this due to increased scatter of electrons at collimator level. Increasing scatter with smaller collimator setting is also indicated by the increase in photon contamination ranging from 1-2.5% for low energies and 3.5-5% for high energies.

Plasma microRNAs predicting clinical outcome in metastatic colorectal cancer patients receiving first-line oxaliplatin-based treatment.

The conventional first-line chemotherapy for metastatic colorectal cancer (mCRC) consists of fluorouracil (5-FU) in combination with either oxaliplatin or irinotecan. We have explored microRNAs (miRNAs) in plasma as potential predictive markers to oxaliplatin-based chemotherapy. The expression of 742 miRNAs was examined in plasma samples from 24 mCRC patients (12 responders and 12 non-responders) before onset and after four cycles of 5-FU/oxaliplatin. The top differentially expressed miRNAs between responders and non-responders were selected for further analysis in a validation cohort of 150 patients. In the validation cohort, there was a significant overrepresentation of miRNAs with higher mean expression in the non-responder group than in the responder group before treatment (p < 0.002). Moreover, we found three miRNAs (miR-106a, miR-484, and miR-130b) to be significantly differentially expressed before treatment (p = 0.008, 0.008, and 0.008, respectively). All three miRNAs were upregulated in non-responders. High expression of miR-27b, miR-148a, and miR-326 were associated with decreased progression-free survival (Hazard ratios (HR) of 1.4 (95% CI 1.1-1.8, p = 0.004), 1.3 (95% CI 1.1-1.6, p = 0.007), and 1.4 (95% CI 1.1-1.8, p = 0.008), respectively). miR-326 was also associated with decreased overall survival (HR 1.5 (95% CI 1.1-2.0, p = 0.003)). There were no significantly differentially expressed miRNAs in association with clinical outcome after four cycles of chemotherapy. The present study demonstrates that plasma miRNAs analyzed before treatment may serve as non-invasive markers predicting outcome in mCRC patients treated with 5-FU and oxaliplatin-based chemotherapy.