Impact of KRAS, BRAF and microsatellite instability status after cytoreductive surgery and HIPEC in a national cohort of colorectal peritoneal metastasis patients

BACKGROUND

Patients with metastatic colorectal cancer (mCRC) carrying BRAF (mutBRAF) or KRAS mutation (mutKRAS) have an inferior prognosis after liver or lung surgery, whereas the prognostic role in the context of peritoneal metastasis (PM) after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has been less investigated.

METHODS

In total, 257 patients with non-appendiceal PM-CRC were included from the Norwegian National Unit for CRS-HIPEC.

RESULTS

In total, 180 patients received CRS-HIPEC with Mitomycin C, 77 patients received palliative surgery only. In the CRS-HIPEC group, mutBRAF was found in 24.7%, mutKRAS 33.9% and double wild-type 41.4% without differences in survival. MSI was found in 29.3% of mutBRAF cases. Patients with mutBRAF/MSI had superior 5-year survival compared to mutBRAF with MSS (58.3% vs 25.2%, P = 0.022), and better 3-year disease-free survival (DFS) compared to mutKRAS (48.6% vs 17.2%, P = 0.049). Peritoneal Cancer Index and the number of lymph node metastasis were prognostic for OS, and the same two, location and gender prognostic for DFS in multivariate analysis.

CONCLUSIONS

PM-CRC with CRS-HIPEC patients has a surprisingly high proportion of mutBRAF (24.7%). Survival was similar comparing mutBRAF, mutKRAS and double wild-type cases, whereas a small subgroup with mutBRAF and MSI had better survival. Patients with mutBRAF tumours and limited PM should be considered for CRS-HIPEC.

ENETS standardized (synoptic) reporting for molecular imaging studies in neuroendocrine tumours

The European Neuroendocrine Tumor Society (ENETS) promotes practices and procedures that aim to improve the standard of care delivered to patients diagnosed with or suspected of having neuroendocrine neoplasia (NEN). At its annual Scientific Advisory Board Meeting in 2018, experts in imaging, pathology and clinical care of patients with NEN drafted guidance for the standardised reporting of diagnostic studies critical to the diagnosis, grading, staging and treatment of NEN. These included pathology, radiology, endoscopy and molecular imaging procedures. In an iterative process, a synoptic reporting template for molecular imaging procedures was developed to guide personalised therapies. Following pilot implementation and refinement within the ENETS Center of Excellence network, harmonisation with specialist imaging societies including the Society of Nuclear Medicine, European Association of Nuclear Medicine and the International Cancer Imaging Society will be pursued.

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.

Population-based study on resection rates and survival in patients with colorectal liver metastasis in Norway

Background

Detailed knowledge about the proportion of patients with colorectal liver metastases (CLM) undergoing resection is sparse. The aim of this study was to analyse cumulative resection rates and survival in patients with CLM.

Methods

For this population-based study of patients developing CLM during 2011–2013, data were extracted from the Norwegian Patient Registry and the Cancer Registry of Norway.

Results

A total of 2960 patients had CLM; their median overall survival was 10·9 months. Liver resection was performed in 538 patients. The cumulative resection rate was 20·0 per cent. The cumulative resection rate was 23·3 per cent in patients aged less than 40 years, 31·1 per cent in patients aged 40–59 years, 24·7 per cent in those aged 60–74 years, 17·9 per cent in those aged 75–79 years and 4·7 per cent in patients aged 80 years or more (P &lt; 0·001). In multivariable analysis, resection rate was associated with age, extrahepatic metastases, disease-free interval and geographical region. Overall survival after diagnosis of CLM was affected by liver resection (hazard ratio (HR) 0·54, 95 per cent c.i. 0·34 to 0·86), rectal cancer (HR 0·82, 0·74 to 0·90), metachronous disease (HR 0·66, 0·60 to 0·74), increasing age (HR 1·32, 1·28 to 1·37), region, and extrahepatic metastases (HR 1·90, 1·74 to 2·07). Three- and 4-year overall survival rates after hepatectomy were 73·2 and 54·8 per cent respectively.

Conclusion

The cumulative resection rate in patients with CLM in Norway between 2011 and 2013 was 20 per cent. Resection rates varied across geographical regions, and with patient and disease characteristics.

Local recurrence rates after radiofrequency ablation or resection of colorectal liver metastases. Analysis of the European Organisation for Research and Treatment of Cancer #40004 and #40983

AIM

The aim of this study is to describe local tumour control after radiofrequency ablation (RFA) and surgical resection (RES) of colorectal liver metastases (CLM) in two independent European Organisations for Research and Treatment of Cancer (EORTC) studies.

BACKGROUND

Only 10-20% of patients with newly diagnosed CLM are eligible for curative RES. RFA has found a place in daily practice for unresectable CLM. There are no prospective trials comparing RFA to RES for resectable CLM.

METHODS

The CLOCC trial randomised 119 patients with unresectable CLM between RFA (±RES)+adjuvant FOLFOX (±bevacizumab) versus FOLFOX (±bevacizumab) alone. The EPOC trial randomised 364 patients with resectable CLM between RES±perioperative FOLFOX. We describe the local control of resected patients with lesions ≤4 cm in the perioperative chemotherapy arm of the EPOC trial (N=81) and the RFA arm of the CLOCC trial (N=55).

RESULTS

Local recurrence (LR) rate for RES was 7.4% per patient and 5.5% per lesion. LR rate for RFA was 14.5% per patient and 6.0% per lesion. When lesion size was limited to 30 mm, LR rate for RFA lesions was 2.9% per lesion. Non-local hepatic recurrences were more often observed in RFA patients than in RES patients, 30.9% and 22.3% respectively. Patients receiving RFA had a more advanced disease.

CONCLUSIONS

LR rate after RFA for lesions with a limited size is low. The local control per lesion does not appear to differ greatly between RFA and surgical resection. This study supports the local control of RFA in patients with limited liver metastases. Future studies should evaluate in which patients RFA could be an equal alternative to liver resection.

Age-dependent improvement in median and long-term survival in unselected population-based Nordic registries of patients with synchronous metastatic colorectal cancer

BACKGROUND

In metastatic colorectal cancer (mCRC) trials, median survival has increased from 6 months to above 20 months during the previous decades. Uncertainty exists in how this survival improvement has translated to the general mCRC population.

PATIENTS AND METHODS

Survival data from patients with synchronous mCRC were collected from the Norwegian (1980-2008), Swedish (1996-2008) and Danish (2001-09) cancer registries.

RESULTS

A total of 29 628 patients were identified. From 1980-1985 to 2006-2008, median survival increased from 5 to 10 months for Norwegian patients. Three-year survival increased from 7% to 21% and 5-year survival from 4% to 9%. For patients <60 years, median survival was doubled to 16 months, 3-year survival increased fourfold up to 28% and 5-year survival threefold up to 14%. Similar improvements were seen in Sweden and Denmark. In all countries, the improved outcome was seen especially for younger patients and much less for patients >75 years of age.

CONCLUSION

An increase in median and long-term survival over time was found in unselected population-based registries of patients with synchronous mCRC. The improved outcome in survival was especially seen in younger patients, raising concerns over our ability to adapt available treatment options for elderly patients.

Predictive and prognostic factors for treatment and survival in 305 patients with advanced gastrointestinal neuroendocrine carcinoma (WHO G3): the NORDIC NEC study

BACKGROUND

As studies on gastrointestinal neuroendocrine carcinoma (WHO G3) (GI-NEC) are limited, we reviewed clinical data to identify predictive and prognostic markers for advanced GI-NEC patients.

PATIENTS AND METHODS

Data from advanced GI-NEC patients diagnosed 2000-2009 were retrospectively registered at 12 Nordic hospitals.

RESULTS

The median survival was 11 months in 252 patients given palliative chemotherapy and 1 month in 53 patients receiving best supportive care (BSC) only. The response rate to first-line chemotherapy was 31% and 33% had stable disease. Ki-67<55% was by receiver operating characteristic analysis the best cut-off value concerning correlation to the response rate. Patients with Ki-67<55% had a lower response rate (15% versus 42%, P<0.001), but better survival than patients with Ki-67≥55% (14 versus 10 months, P<0.001). Platinum schedule did not affect the response rate or survival. The most important negative prognostic factors for survival were poor performance status (PS), primary colorectal tumors and elevated platelets or lactate dehydrogenase (LDH) levels.

CONCLUSIONS

Advanced GI-NEC patients should be considered for chemotherapy treatment without delay.PS, colorectal primary and elevated platelets and LDH levels were prognostic factors for survival. Patients with Ki-67<55% were less responsive to platinum-based chemotherapy, but had a longer survival. Our data indicate that it may not be correct to consider all GI-NEC as one single disease entity.

Randomized phase III study of 5-fluorouracil/folinate/oxaliplatin given continuously or intermittently with or without cetuximab, as first-line treatment of metastatic colorectal cancer: The NORDIC VII study (NCT00145314), by the Nordic Colorectal Cancer Biomodulation Group

365

Background: The role of anti-EGFR therapy in first-line treatment of metastatic colorectal cancer (mCRC) is not established. In the present study pts were randomized to FLOX or FLOX + cetuximab until progression or FLOX intermittently + cetuximab continuously.

Methods: Treatment arm A: Nordic FLOX (q2w): oxaliplatin 85 mg/m2day 1, 5-FU bolus 500 mg/m2 and FA 60 mg/m2 day 1-2; B: FLOX + cetuximab, initial dose 400 mg/m2, then 250 mg/m2/week; C: FLOX for 16 weeks + cetuximab continuously, with FLOX added at progression. Primary endpoint was progression-free survival (PFS).

Results: Between May 05-Oct 07, 571 pts were randomized, 566 pts evaluable in intention to treat (ITT) analyses. Median age was 61 (24-74). ECOG status: 0=67%, 1=29%, 2=4%. KRAS and BRAF mutation (mut) analyses were obtained in 498 (87%) and 457 pts (81%), respectively. 40% of tumors had KRAS mut, 12% had BRAF mut. Cetuximab combined with Nordic FLOX did not significantly improve RR, PFS or OS compared to FLOX. KRAS mutation was not predictive for cetuximab effect. OS was similar for patients treated with FLOX intermittently and cetuximab continuously as for patients treated until progression. BRAF mutation was a strong negative prognostic factor (median OS 7.6 vs. 20.4 mo).

Conclusions: Cetuximab did not add significant benefit to the Nordic FLOX regimen in first-line treatment of mCRC, irrespective of KRAS-mut.

[Table: see text]

[Table: see text]

Patient characteristics and stratification in medical treatment studies for metastatic colorectal cancer: A proposal for standardization of patient characteristic reporting and stratification

BACKGROUND

Prognostic factors have the potential to determine the survival of patients to a greater extent than current antineoplastic agents. Despite this knowledge, there is no consensus on, first, what patient characteristics to report and, second, what stratification factors to use in metastatic colorectal cancer trials.

PATIENTS AND METHODS

Seven leading oncology and medical journals were reviewed for phase II and III publications reporting on medical treatment of metastatic colorectal cancer patients during 2001-2005. One hundred and forty-three studies with 21 214 patients were identified. The reporting of patient characteristics and use of stratification was noted.

RESULTS

Age, gender, performance status, metastases location, sites and adjuvant chemotherapy were often reported (99-63%). Laboratory values as alkaline phosphatase, lactate dehydrogenase and white blood cell count, repeatedly found to be of prognostic relevance, were rarely reported (5-9%). Stratification was used in all phase III trials; however, only study centre was used with any consistency.

CONCLUSION

There is considerable inconsistency in the reporting of patient characteristics and use of stratification factors in metastatic colorectal cancer trials. We propose a standardization of patient characteristics reporting and stratification factors. A common set of characteristics and strata will aid in trial reporting, interpretation and future meta-analyses.

Final results of the EORTC Intergroup randomized phase III study 40983 [EPOC] evaluating the benefit of peri-operative FOLFOX4 chemotherapy for patients with potentially resectable colorectal cancer liver metastases

LBA5

Background: The 5-year survival after resection of colorectal cancer liver metastases is 30% but recurrence is common. This study evaluates the benefit of combining peri-operative chemotherapy and surgery for patients with initially resectable liver only metastases from colorectal cancer (LM). Methods: Between September 2000 and July 2004, 364 pts with up to 4 LM were randomized between peri-operative FOLFOX4 (oxaliplatin 85mg/m2 and LV5FU2), 6 cycles before and 6 cycles after surgery, (CT), and surgery alone (S). The primary endpoint was progression free survival (PFS) with the goal to increase median PFS by 40% (HR=0.71). Safety was a secondary endpoint (already reported at ASCO 2005). PFS results are reported at the 2-sided 0.0434 significance level (adjusting for one interim analysis). Results: Baseline characteristics were similar in both arms. Eleven of 182 pts were ineligible in each arm, mostly for more advanced disease. In the CT arm, a median of 6 pre-op cycles were delivered and 151 patients were resected. 115 pts (63%) received post-op CT, with a median number of 6 cycles and a relative dose intensity of 79% to 86%. In the S arm, 152 pts were resected. Due to the nature of the trial, evaluation of resectability (relevant for eligibility) was based on pre-op imaging, but 31/182 pts (CT arm) and 30/182 pt (S arm) could not undergo resection. There were 2 (S arm) and 1 (CT arm) deaths after surgery. At a median follow-up of 3.9 years, 254 PFS events were reported (240 in eligible pts) and the results are as shown in the table . Conclusions: Peri-operative FOLFOX4 chemotherapy improved PFS over surgery alone in patients whose metastases were actually resected. The benefit was slightly diluted when also pts considered resectable on imaging but eventually not resected were taken into account. FOLFOX4 given peri-operatively is safe and does not prevent the pts from undergoing surgery. [Table: see text]

[Table: see text]

Tumor response to pre-operative chemotherapy (CT) with FOLFOX-4 for resectable colorectal cancer liver metastases (LM). Interim results of EORTC Intergroup randomized phase III study 40983

3500

Background: After resection of LM, 5y survival is 30%, but cancer recurrence is frequent. The benefit of combining surgery and CT has not yet formally been proven. Methods: This study evaluates the value of pre- and postoperative CT in patients with potentially resectable liver metastases from colorectal cancer. Between September 2000 and July 2004, 364 patients were randomized between peri-operative FOLFOX4 (oxaliplatin 85mg/m2 and LV5FU2), 6 cycles before and 6 cycles after surgery (182 patients), and surgery alone (182 patients). The primary endpoint was progression free survival. The purpose of this analysis was to evaluate tumor response to pre-operative treatment and determine if CT induces a tumor size reduction. Results: Baseline characteristics were similar in both arms: median age: 62.5 yrs, prior adjuvant CT: 41.8%, 1 to 3 metastases: 92.3%, T3 or T4: 80.8%. In the CT arm, 97.7% of the patients were documented to have completed pre-operative CT (81.5% received 6 preoperative cycles). 28.9% of the patients who started pre-operative CT required a dose reduction. Of all patients entered in the trial, 88.3% and 94.9% underwent surgery in the CT and surgery arms, respectively. Resection was achieved in 95.6% of the patients operated (84.4% of all patients) in the CT arm, and 89.2% of the patients operated (84.7% of all patients) in the surgery arm. As previously reported, preoperative chemotherapy was safely administered. From imaging data (CT scan), median sum of largest diameters of lesions was 45 mm [Q1-Q3:28.0–70.0] (both arms) before treatment and decreased to 30 mm [Q1-Q3: 15.0–55.0] after CT (median relative difference of 29.7%). At pathological examination, median sum of largest diameters of lesions was 34.5 mm [Q1-Q3:20.0–53.0] in the CT arm and 45 mm [Q1-Q3: 29.0–69.0] in the surgery arm. Conclusions: CT scan measurements were consistent with those performed at pathological examination. Pre-operative CT with 6 cycles of FOLFOX4 resulted in a decrease in diameter of lesions. Since size of metastases at time of surgery is known to have an impact on survival, it is possible that preoperative chemotherapy will improve survival. Survival data should be available at the end of 2006.

No significant financial relationships to disclose.