Analysis of Circulating Immune Subsets in Primary Colorectal Cancer.

The development and progression of colorectal cancer (CRC) are known to be affected by the interplay between tumor and immune cells. However, the impact of CRC cells on the systemic immunity has yet to be elucidated. We aimed to comprehensively evaluate the circulating immune subsets and transcriptional profiles of CRC patients. In contrast to healthy controls (HCs), CRC patients had a lower percentage of B and T lymphocytes, T helper (Th) cells, non-classical monocytes, dendritic cells, and a higher proportion of polymorphonuclear myeloid-derived suppressor cells, as well as a reduced expression of CD69 on NK cells. Therefore, CRC patients exhibit a more evident systemic immune suppression than HCs. A diagnostic model integrating seven immune subsets was constructed to distinguish CRC patients from HCs with an AUC of 1.000. Moreover, NR3C2, CAMK4, and TRAT1 were identified as candidate genes regulating the number of Th cells in CRC patients. The altered composition of circulating immune cells in CRC could complement the regional immune status of the tumor microenvironment and contribute to the discovery of immune-related biomarkers for the diagnosis of CRC.

First-line fluoropyrimidine plus bevacizumab followed by irinotecan-escalation versus initial fluoropyrimidine, irinotecan and bevacizumab in patients with metastatic colorectal cancer - Final survival and per-protocol analysis of the randomised XELAVIRI trial (AIO KRK 0110).

BACKGROUND: The randomised open-label phase III XELAVIRI trial failed to demonstrate non-inferiority of the sequential application of fluoropyrimidine plus bevacizumab followed by additional irinotecan at first progression (Arm A) versus initial combination of all agents (Arm B) for untreated metastatic colorectal cancer in the initial analysis of time-to-failure-of-strategy (TFS, 90% confidence boundary of 0.8). Here, we evaluate efficacy in the full analysis set (FAS), the per-protocol set, in addition to age-related and molecular subgroups. METHODS: Median TFS, overall survival (OS) and progression-free survival (PFS) were estimated by Kaplan-Meier method and log-rank test. Cox regression models assessed hazard ratios (HRs) and confidence intervals (CIs) (TFS: 90%; OS, PFS: 95%). RESULTS: Of 421 patients, 390 (92.6%), 391 (92.9%) and 357 (84.8%) events for TFS, OS and PFS were observed in the FAS with a median follow-up of 54.2 months (Arm A) versus 52.9 months (Arm B). Non-inferiority of sequential treatment for TFS was missed in the FAS (HR 0.93; 90% CI, 0.79-1.10; P = 0.482) and not shown in the per-protocol set (HR 0.93; 90% CI, 0.75-1.13, P = 0.433). Formal non-inferiority for TFS was observed for patients older than 70 years (HR 1.06; 90% CI, 0.80-1.41; P = 0.670) and patients with RAS mutant tumours (HR 1.12; 90% CI, 0.87-1.43; P = 0.465). In RAS/BRAF wild-type tumours, combination treatment was significantly superior to sequential therapy in all end-points. CONCLUSIONS: In the overall population, XELAVIRI just missed to demonstrate the non-inferiority of sequential compared to combination therapy for TFS. However, the non-inferiority of sequential treatment was observed in elderly patients and RAS mutant tumours. TRIAL REGISTRATION: Trial registration ID (clinicaltrials.gov) NCT01249638.

Consensus molecular subtypes in metastatic colorectal cancer treated with sequential versus combined fluoropyrimidine, bevacizumab and irinotecan (XELAVIRI trial).

BACKGROUND: The XELAVIRI trial compared sequential (fluoropyrimidine and bevacizumab; irinotecan (Iri) at progression) versus initial combination therapy (fluoropyrimidine, bevacizumab, Iri) of treatment-naïve metastatic colorectal cancer (mCRC). In the confirmatory analysis, the primary end-point (non-inferiority of sequential therapy regarding time to failure of strategy, TFS) was not met. Nevertheless, significant differences regarding treatment efficacy were observed according to RAS status. Here, we evaluate the consensus molecular subtypes (CMS) as additional biomarkers for sequential versus combination therapy. MATERIAL AND METHODS: Gene expression was measured using NanoString after mRNA extraction from formalin-fixed paraffin-embedded tumour specimens. CMS were predicted using multinomial regression and correlated with updated data for TFS, overall (OS) and progression-free survival. RESULTS: CMS were predicted in 337 of 421 (80.0%) patients (CMS1: 18.4%; CMS2: 51.6%; CMS3: 2.7%; CMS4: 27.3%). CMS2 together with RAS/BRAF wild-type status was identified as potential predictive marker of benefit from initial combination therapy for OS (HR 0.56, 95% CI 0.33-0.96, p = 0.036) and progression-free survival (HR 0.28, 95% CI 0.29-0.79, p = 0.004) and also trending in TFS (HR 0.63, 90% CI 0.41-0.95, p = 0.066). In patients with RAS-mutated mCRC, CMS1 was associated with longer OS after initial combination therapy (HR 0.43, 95% CI 0.20-0.95, p = 0.038). Interaction testing (two-sided) of CMS and RAS/BRAF status in favour of the combination treatment strategy was significant for OS (p = 0.012) CONCLUSIONS: In patients with RAS/BRAF wild-type mCRC, CMS2 may serve as an additional biomarker of benefit from the initial combination therapy, including Iri. TRIAL REGISTRATION: Trial registration ID (clinicaltrials.gov) NCT01249638.

Coincidental SARS-CoV-2 infection and mRNA vaccination: a case report addressing the most important clinical questions.

The case describes the coincidental mRNA vaccination and SARS-CoV-2 infection of a 31-year-old physician addressing the theoretical considerations and recommendations for further actions in such a particular constellation that we will expect more often in the near future.

[Acute Facial Swelling Following Dental Procedure - an Allergic Reaction?] / Akute Gesichtsschwellung nach Zahnbehandlung: eine allergische Reaktion?

The most common cause of facial edema after dental or medical treatment is an allergic reaction. At our emergency department, a 58-year old female patient presenting with swollen right face after dental crown preparation, was initially treated with antiallergic medication. After three hours the patient was stable, swelling was still present and then crepitus could be observed on second palpation. Cervicofacial subcutaneous emphysema was confirmed with an unenhanced CT of the head and paranasal sinus; it is a rare complication after dental treatment and within the last years only few cases have been reported. Reported complications are pneumothorax and -pericardium, mediastinitis or air embolism, so early recognition is important. Our case report depicts diagnostic and therapeutic steps of this uncommon differential diagnosis.

[Peripheral neuropathy as a side effect of chemotherapy and targeted therapy]. / Chemotherapie-induzierte periphere Neuropathie.

Chemotherapy-induced peripheral neuropathy (CIPN) is a severe and common side effect induced by a variety of anticancer drugs. CIPN presents as a sensory, motor, and sometimes autonomic dysfunction with a large variability, from a mild tingling sensation and hyperesthesia, to severe neuropathic pain. Up to 40 % of patients will develop CIPN which may lead to dose-reduction or discontinuation of their current treatment and largely affects their quality of life (QoL). This review presents specific clinical features and pathomechanisms and discusses current preventive strategies and therapeutic options.

Assessing novel prognostic serum biomarkers in advanced pancreatic cancer: the role of CYFRA 21-1, serum amyloid A, haptoglobin, and 25-OH vitamin D3.

The present prospective single-center study investigated the prognostic role of novel serum biomarkers in advanced pancreatic cancer (PC). Patients (pts) with locally advanced or metastatic PC treated with first-line palliative chemotherapy were included. Among others, the serum markers CYFRA 21-1, haptoglobin, serum-amyloid A (SAA), and 25-OH vitamin D3 were determined at baseline and categorized by pre-defined cut-offs [median values (MV), upper limits of normal (ULN), lower limits of normal (LLN), or the natural logarithm (ln)] and correlated with overall survival (OS). Among the 59 pts included, pre-treatment CYFRA 21-1 levels showed a strong correlation with OS independent of the applied cut-off (MV 4.9 ng/ml-14.2 vs. 4.2 months, HR 0.18, p = 0.001; ULN 3.3 ng/ml-14.2 vs. 4.4 months, HR 0.28, p = 0.003; [ln] CYFRA 21-1-HR 0.77, p = 0.013). Lower values of haptoglobin were additionally associated with an improvement in OS (categorized by LLN of 2.05 g/l-10.4 vs. 5.5 months, HR 0.46, p = 0.023; [ln] haptoglobin-HR 0.51, p = 0.036). Pts with baseline SAA values below the MV of 22 mg/l also had a prolonged OS (10.4 vs. 5.0 months, HR 0.47, p = 0.036). For 25-OH vitamin D3 levels, no significant correlation with OS was found. In multivariate analyses, pre-treatment CYFRA 21-1 levels (categorized by MV-HR 0.15, p = 0.032) as well as [ln] haptoglobin (HR 0.30, p = 0.006) retained their independent prognostic significance for OS. CYFRA 21-1, haptoglobin, and SAA might provide useful prognostic information in advanced PC. An external multicenter validation of these results is necessary.

Effect of KRAS exon 2 mutations on antitumor activity of afatinib and gefitinib.

The aim of this study was to investigate the impact of different KRAS mutations on the inhibitory potential of afatinib and gefitinib in SW48 colorectal cancer cells. The influence of afatinib/gefitinib on cell viability and cell cycle was evaluated in isogenic SW48 KRAS wild-type/mutant cells. Protein levels of phosphorylated/total EGFR, HER-2, HER-3, ERK, and AKT were compared between treated/untreated samples using western blotting. The activity of both afatinib and gefitinib was the lowest in KRAS G12C/G12S/G12D and the highest in G13D/G12A mutant subtypes. A 50% decrease in cell viability was achieved at concentrations of 3.0-7.7 µmol/l for afatinib and 5.4-19.5 µmol/l for gefitinib. The effect of both drugs on apoptosis appeared to be stronger than their influence on proliferation and was generally less pronounced in mutant cells than in wild-type cells. The average number of apoptotic cells after treatment with afatinib was 2.6 times as high as the corresponding value following treatment with gefitinib (P<0.01). Levels of pEGFR, pHER-2, pERK, and pAKT were reduced more extensively by afatinib than by gefitinib (P<0.001). Some KRAS mutations (G12C/G12S/G12D) appear to weaken the activity of afatinib and gefitinib whereas others seem to increase sensitivity to treatment (G13D/G12A) compared with the parental clone (KRAS wild-type). In SW48 colorectal cancer cells, afatinib seems to be more potent than gefitinib because of its superior efficacy in inhibiting both EGFR and HER-2, suppressing signaling along both MEK/ERK and PI3K/AKT pathways to a greater extent.

NeoFLOT: Multicenter phase II study of perioperative chemotherapy in resectable adenocarcinoma of the gastroesophageal junction or gastric adenocarcinoma-Very good response predominantly in patients with intestinal type tumors.

Perioperative treatment is a standard of care in locally advanced gastroesophageal cancer (GEC) (gastric adenocarcinoma and gastroesophageal junction (GEJ) adenocarcinoma). While preoperative treatment can be applied to the majority of patients, postoperative chemotherapy can be given only to a fraction. The NeoFLOT-study therefore investigates the application of prolonged neoadjuvant chemotherapy (NACT). Patients with T3, T4, and/or node-positive adenocarcinoma (GEC) were eligible for this multicenter phase II trial. NACT consisted of 6 cycles of oxaliplatin 85 mg/m(2) , leucovorin 200 mg/m(2) , 5-fluorouracil 2600 mg/m(2) and docetaxel 50 mg/m(2) (FLOT) applied q 2 wks. Application of adjuvant chemotherapy was explicitly not part of the protocol. R0-resection rate was evaluated as a primary endpoint. Of 59 enrolled patients, 50 patients underwent surgery and were assessable for the primary endpoint. R0-resection rate was 86.0% (43/50). Pathologic complete response (pCR) was 20.0% (10/50) and a further 20% (10/50) of patients achieved near complete histological remission (<10% residual tumor). Among these very good responders, 85% (17/20) had intestinal type tumors, 10% (2/20) had diffuse and 5% (1/20) had mixed type tumors. After 3 cycles of NACT, 6.9% (4/58) of patients developed progressive disease. Median disease-free survival was 32.9 months. The 1-year survival-rate was 79.3%. Grade 3-4 toxicities included neutropenia 29.3%, febrile neutropenia 1.7%, diarrhea 12.1% and mucositis 6.9%. This study indicates that intensified NACT with 6 cycles of FLOT is highly effective and tolerable in resectable GEC. Very good response (pCR and <10% residual tumor) was predominantly observed in patients with intestinal type tumors.

Surrogate endpoints in second-line treatment for mCRC: a systematic literature-based analysis from 23 randomised trials.

PURPOSE: To evaluate progression-free survival (PFS), overall response rate (ORR) and disease control rate (DCR) as potential surrogate endpoints (SEP) for overall survival (OS) in second-line treatment for metastatic colorectal cancer (mCRC). METHODS: A systematic literature search of randomised trials of second-line chemotherapy for mCRC reported from January 2000 to July 2013 was performed. Correlation coefficients weighted by number of patients in the treatment arms between median PFS, ORR and DCR with median OS were estimated. RESULTS: Twenty-three trials reflecting 10 800 patients met the inclusion criteria. Median PFS and OS across all trials were 4.5 months and 11.5 months and median ORR and DCR were 11.4% and 65%, respectively. PFS showed moderate correlation with OS [RPFS = 0.73; 95% confidence interval (CI) 0.61-0.82]. In contrast, ORR only weakly correlated with OS (RORR = 0.58; 95% CI 0.38-0.72, n = 22). Despite a small number of studies (n = 10) reporting on DCR, moderate correlation with OS was observed (RDCR = 0.74; 95% CI 0.56-0.86). CONCLUSION: Based on the available trial-level data, PFS may serve as an appropriate SEP in second-line chemotherapy for mCRC. A small number of studies revealed moderate correlation of DCR with OS that justifies further investigation.

Trip to immunity: resistant cytomegalovirus infection in a lung transplant recipient.

We report the case of a young female lung transplant recipient with difficult-to-treat cytomegalovirus (CMV) disease. While treatment with intravenous (IV) ganciclovir failed due to antiviral drug resistance, a trial with foscarnet resulted in severe side effects. In addition, the patient received IV CMV-specific immune globulins as adjunctive therapy and leflunomide as experimental therapy. In this context, CMV-specific immune monitoring was performed and was successfully implemented in management decisions. The patient was screened for acquisition of an adaptive immune response, and antiviral prophylaxis and therapy was tailored according to results. This report highlights the impact of CMV-specific immune monitoring on individualized therapy for appropriate prophylaxis and management of CMV infection and diseases.

Evaluation of preoperative serum markers for individual patient prognosis in stage I-III rectal cancer.

Several independent serum biomarkers have been proposed as prognostic and/or predictive markers for colorectal cancer (CRC). To this date, carcinoembryonic antigen (CEA) remains the only recommended serological CRC biomarker. The present retrospective analysis investigates the prognostic value of several serum markers. A total of 256 patients with rectal cancer underwent surgery for curative intent in a university cancer center between January 1988 and June 2007. Preoperative serum was retrospectively analyzed for albumin, alkaline phosphatase (aP), beta-human chorionic gonadotropin, bilirubin, CA 125, cancer antigen 19-9, cancer antigen 72-4 (CA 72-4), CEA, CRP, CYFRA 21-1, ferritin, gamma-glutamyl transpeptidase, glutamate oxaloacetate transanunase, glutamate pyruvate transaminase, hemoglobin, haptoglobin, interleukin-6, interleukin-8, creatinine, lactate-dehydrogenase, serum amyloid A (SAA), and 25-hydroxyvitamin D. Cancer-specific survival (CSS) and disease-free survival (DFS) were estimated. Median follow-up time was 8.4 years. Overall 3- and 5-year CSS was 88.6 and 78.9 %, respectively. DFS rates were 72.8 % (3 years) and 67.5 % (5 years). Univariate analysis of CSS indicated aP, CA 72-4, CEA, and SAA as prognostic factors, while aP, CEA, and SAA were also prognostic with regard to DFS. Multivariate analysis confirmed SAA together with T and N stage as prognostic factors. According to UICC stage, CEA and SAA add prognostic value in stages II and III with regard to DFS and CSS, respectively. The combined use of CEA and SAA is able to identify patients with favorable and poor prognosis. In addition to tumor baseline parameters, routine analysis of SAA together with CEA provided markedly improved prognostic value on CSS and DFS in resected rectal cancer.

Outcome of patients with metastatic colorectal cancer depends on the primary tumor site (midgut vs. hindgut): analysis of the FIRE1-trial (FuFIRI or mIROX as first-line treatment).

The aim of this study was to investigate the impact of midgut versus hindgut as the primary tumor site in patients with metastatic colorectal cancer (mCRC) receiving chemotherapy with FuFIRI or mIROX. We analyzed 423 patients from a phase III trial that randomized patients in a 1 : 1 fashion to either FuFIRI or mIROX. The cohort was grouped into midgut (n=82) and hindgut (n=341) primary tumors. The primary tumor site (midgut vs. hindgut) was correlated with parameters of treatment efficacy and survival. Our cohort comprised 82 patients presenting with primary midgut tumors and 341 with primary hindgut tumors. Tumors of midgut origin compared with hindgut origin were associated with inferior outcome. Objective response rate was 37 versus 43% (P=0.34), median progression-free survival was 6.0 versus 8.2 months (P=0.024, hazard ratio: 0.75), and median overall survival was 13.6 versus 21.8 months (P=0.001, hazard ratio: 0.65). Patients with midgut mCRC showed a clear trend toward inferior outcome in both study arms. However, the effect appeared less pronounced in the mIROX arm. Further datasets from large trials with various regimens are required as confirmation.

Clinical relevance and utility of cetuximab-related changes in magnesium and calcium serum levels.

Hypomagnesemia and hypocalcemia are common adverse events during cetuximab treatment. The influence of the chemotherapeutic combination on serum levels is unknown and the predictive value is currently under discussion. This analysis investigated 79 patients who had received cetuximab for at least 6 weeks in the day clinic of the Comprehensive Cancer Center, University of Munich. Calcium and magnesium serum levels were analyzed weekly; tumor response and adverse events were followed. Thirty-eight patients had metastatic colorectal cancer (mCRC) and the predictive value of hypomagnesemia was tested in these patients. During therapy, calcium serum levels decreased to about 97% of the baseline levels and were maintained for the duration of treatment. Magnesium levels showed a significant time-dependent decrease. Serum levels of magnesium were lower when cetuximab was combined with a platinum derivative. After a treatment duration of 12 weeks, magnesium levels decreased to 70% in platinum-treated patients, whereas they decreased to only 90% of baseline in patients who did not receive platinum therapy. In patients treated for mCRC, a decrease of serum magnesium below 95% of the baseline levels 14 days after initiating treatment separated patients significantly in terms of survival times. Magnesium levels decrease in a time-dependent manner during cetuximab therapy. As hypomagnesemia was more prominent in patients receiving platinum agents, magnesium measurements may be advised in these patients. In mCRC patients treated with cetuximab, day-14 magnesium serum levels correlated with treatment efficacy.

Early tumor shrinkage in metastatic colorectal cancer: retrospective analysis from an irinotecan-based randomized first-line trial.

Early tumor shrinkage (ETS) has been highlighted as a favorable prognostic factor related to progression-free survival (PFS) and overall survival (OS) in cytotoxic treatment of metastatic colorectal cancer. Data from a randomized phase III study comparing infusional 5-fluorouracil plus irinotecan (FUFIRI) versus irinotecan plus oxaliplatin (mIROX) were evaluated. Patient groups were analyzed according to the relative change in maximum tumor diameter between baseline and after 7 weeks of treatment. The ETS cohort was defined as a decrease of ≥20%. Additionally, the non-ETS cohort was subdivided into "minor shrinkage" (0-19%), "tumor progression" (any increase) and development of "new metastatic lesions". Progression-free survival and OS were estimated in all patient subgroups. Assessment of ETS was possible in 201 patients. Early tumor shrinkage was observed in 47% (94/201) and non-ETS in 53% (107/201) of patients. Patients with ETS had a more favorable outcome with regard to PFS (9.9 months vs 6.1 months, P = 0.029) and OS (27.5 months vs 17.8 months, P = 0.002). In the non-ETS subgroups, patients with "minor shrinkage" (PFS 8.4 months, OS 21.6 months) showed a markedly better outcome than patients with "early tumor progression" (PFS 4.0 months, OS 15.3 months) or with "new metastatic lesions (PFS 2.2 months, OS 7.6 months). In conclusion, ETS assessment offers accelerated response evaluation when compared to RECIST. In patients treated with chemotherapy alone, ETS ≥20% is associated with excellent outcome. Non-ETS is a heterogeneous subgroup where patients with minor shrinkage clearly benefit from treatment, and patients with early progression or development of new lesions have an unfavorable prognosis.

Combined resection of colorectal hepatic-pulmonary metastases shows improved outcome over chemotherapy alone.

BACKGROUND: The objective of this retrospective study was to assess the survival of patients after resection of hepatic and pulmonary colorectal metastases to identify predictors of long-term survival. METHODS: Patients receiving chemotherapy alone were compared to patients receiving surgery and chemotherapy in a matched-pair analysis with the following criteria: UICC stage, grading, and date of initial primary tumor occurrence. RESULTS: A total of 30 patients with liver and lung metastases of colorectal carcinoma underwent resection. In 20 cases, complete resection was achieved (median survival, 67 months). Incomplete resection and preoperatively elevated carcinoembryonic antigen (CEA) levels are independent risk factors for reduced survival. Patients developing pulmonary metastases prior to hepatic metastases had the worst prognosis. Surgical resection significantly increased survival compared to chemotherapy alone in matched-pair analysis (65 vs. 30 months, p = 0.03). CONCLUSIONS: Incomplete resection and elevated CEA levels are predictors of poor outcome. Matched-paired analysis confirmed that surgical resection in combination with chemotherapy appears to be superior to chemotherapy alone.

Prognostic value of cetuximab-related skin toxicity in metastatic colorectal cancer patients and its correlation with parameters of the epidermal growth factor receptor signal transduction pathway: results from a randomized trial of the GERMAN AIO CRC Study Group.

Skin toxicity is a frequent adverse event of epidermal growth factor receptor (EGFR) targeting agents. Occurrence of cetuximab-induced skin toxicity (Cet-ST) correlates with better treatment response and longer survival times. Molecular markers predicting Cet-ST are still missing. This investigation analyzed the value of Cet-ST for treatment efficacy in a randomized trial comparing cetuximab plus capecitabine/irinotecan to cetuximab plus capecitabine/oxaliplatin as first-line treatment of metastatic colorectal cancer. Patient characteristics and molecular parameters (KRAS mutation, EGFR-FISH, EGFR-IHC and EGFR intron-1 polymorphism) of the tumour were correlated with response and Cet-ST. Cet-ST grade 0-1 was observed in 31%, grade 2-3 in 69% of patients. Outcome favoured patients with grade 2-3 Cet-ST with regard to overall response rate (62 vs. 41%), PFS (7.8 vs. 5.2 months) and overall survival (OS) (30.3 vs. 18.0 months). First-cycle rash was observed in 66% of patients and corresponded with longer survival (30.7 vs. 20.2 months, p = 0.007). Patients without Cet-ST had a poor outcome (PFS, 1.9 months; OS, 11 months). The correlation of Cet-ST with survival was specifically evident in patients with KRAS codon-12-mutated tumours assumed to be cetuximab resistant. In multivariate analysis of patient characteristics, male gender and younger age were significantly correlated with Cet-ST. Among molecular parameters, no significant correlation with Cet-ST was found. Cet-ST is an early predictor of treatment efficacy in cetuximab-treated patients. This effect of Cet-ST is independent of the KRAS mutation status, suggesting that Cet-ST rather relates to constitutional factors of the patient than alterations of the EGFR pathway in the tumour.

Progression-free survival as a surrogate endpoint for median overall survival in metastatic colorectal cancer: literature-based analysis from 50 randomized first-line trials.

PURPOSE: To evaluate progression-free survival (PFS) as a potential surrogate endpoint (SEP) for overall survival (OS) in metastatic colorectal cancer (mCRC) with a focus on applicability to trials containing targeted therapy with anti-VEGF- or anti-EGF receptor (EGFR)-directed monoclonal antibodies. EXPERIMENTAL DESIGN: A systematic literature search of randomized trials of first-line chemotherapy for mCRC reported from January 2000 to January 2012 was conducted. Adjusted weighted linear regression was used to calculate correlations within PFS and OS (endpoints; R(EP)) and between treatment effects on PFS and on OS (treatment effects; R(TE)). RESULTS: Fifty trials reflecting 22,736 patients met the inclusion criteria. Correlation between treatment effects on PFS and OS and between the endpoints PFS and OS was high across all studies (R(TE) = 0.87, R(EP) = 0.86). This was also observed in chemotherapy-only trials (R(TE) = 0.93, R(EP) = 0.81) but less so for trials containing monoclonal antibodies (R(TE) = 0.47; R(EP) = 0.52). Limiting the analysis to bevacizumab-based studies (11 trials, 3,310 patients) again yielded high correlations between treatment effects on PFS and on OS (R(TE) = 0.84), whereas correlation within PFS and OS was low (R(EP) = 0.45). In 7 trials (1,335 patients) investigating cetuximab- or panitumumab-based studies, contrasting correlations with very wide confidence intervals were observed (R(TE) = 0.28; R(EP) = 0.96). CONCLUSIONS: PFS showed consistently high correlation with OS of an order that would justify its use as an SEP in chemotherapy regimens. For validation of surrogacy in anti-VEGF and anti-EGFR-directed therapies, further research and a larger set of trials is needed.

Early tumor shrinkage in patients with metastatic colorectal cancer receiving first-line treatment with cetuximab combined with either CAPIRI or CAPOX: an analysis of the German AIO KRK 0104 trial.

PURPOSE: This study investigated the impact of early tumor shrinkage (ETS) on progression-free- (PFS) and overall survival (OS) in patients with metastatic colorectal cancer (mCRC) treated within the AIO KRK 0104 trial as first-line therapy. Moreover, correlations of ETS with clinical characteristics and prognostic markers were evaluated. PATIENTS AND METHODS: In total, 121 patients were included into this analysis. Patients were treated with cetuximab combined with either CAPIRI or CAPOX. ETS at six weeks was defined as a relative change of ≥ 20% in the sum of the longest diameters of target lesions compared to baseline. Survival times were compared between patients with ETS ≥ 20% versus no-ETS. RESULTS: ETS ≥ 20% was observed in 59% of all patients with KRAS wild-type tumors. In these patients ETS ≥ 20% was associated with higher overall response rate (82% vs. 19%, p < 0.001). Also, PFS (8.9 vs. 4.7 months, p < 0.001) and OS (31.6 vs. 15.8 months, p = 0.005) were significantly superior in ETS ≥ 20% of patients compared to no-ETS. In patients with KRAS mutant mCRC ETS ≥ 20% neither had an effect on PFS nor OS. Cetuximab-induced skin toxicity correlated with the occurrence of ETS ≥ 20% (p = 0.002). CONCLUSION: In patients with KRAS wild-type tumors treated with cetuximab plus capecitabine-based chemotherapy ETS ≥ 20% is an important predictor of favorable outcome.