RAS testing of liquid biopsy correlates with the outcome of metastatic colorectal cancer patients treated with first-line FOLFIRI plus cetuximab in the CAPRI-GOIM trial

Background

Liquid biopsy is an alternative to tissue for RAS testing in metastatic colorectal carcinoma (mCRC) patients. Little information is available on the predictive role of liquid biopsy RAS testing in patients treated with first-line anti-EGFR monoclonal antibody-based therapy.

Patients and methods

In the CAPRI-GOIM trial, 340 KRAS exon-2 wild-type mCRC patients received first-line cetuximab plus FOLFIRI. Tumor samples were retrospectively assessed by next generation sequencing (NGS). Baseline plasma samples were analyzed for KRAS and NRAS mutations using beads, emulsion, amplification, and magnetics digital PCR (BEAMing). Discordant cases were solved by droplet digital PCR (ddPCR) or deep-sequencing.

Results

A subgroup of 92 patients with available both NGS data on tumor samples and baseline plasma samples were included in this study. Both NGS analysis of tumor tissue and plasma testing with BEAMing identified RAS mutations in 33/92 patients (35.9%). However, 10 cases were RAS tissue mutant and plasma wild-type, and additional 10 cases were tissue wild-type and plasma mutant, resulting in a concordance rate of 78.3%. Analysis of plasma samples with ddPCR detected RAS mutations in 2/10 tissue mutant, plasma wild-type patients. In contrast, in all tissue wild-type and plasma mutant cases, ddPCR or deep-sequencing analysis of tumor tissue confirmed the presence of RAS mutations at allelic frequencies ranging between 0.15% and 1.15%. The median progression-free survival of RAS mutant and wild-type patients according to tissue (7.9 versus 12.6 months; P = 0.004) and liquid biopsy testing (7.8 versus 13.8 moths; P < 0.001) were comparable. Similar findings were observed for the median overall survival of RAS mutant and wild-type patients based on tissue (22.1 versus 35.8 months; P = 0.016) and plasma (19.9 versus 35.8 months; P = 0.013) analysis.

Conclusion

This study indicates that RAS testing of liquid biopsy results in a similar outcome when compared with tissue testing in mCRC patients receiving first-line anti-EGFR monoclonal antibodies.

A child cohort study from southern Italy enlarges the genetic spectrum of hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is the most frequent genetic cardiovascular disorder worldwide. It is the leading cause of sudden cardiac-related death in young people and a major cause of cardiac failure and death in elderly people. However, HCM frequently goes undiagnosed until the appearance of overt signs and symptoms, thereby delaying prophylactic and therapeutic measures. We screened patients for sarcomeric genes associated with HCM to obtain information that could be useful for an early diagnosis and so limit the severe consequences of silent HCM. We recruited 39 families with HCM from southern Italy and found mutations in 41% of families (12 with familial HCM and 4 with sporadic HCM). The remaining 23 families (59%) were negative for myofilament gene mutations. Of the 12 mutations identified, 8 were novel. Screening of the other family members available revealed that 27 had mutations; 11 of these individuals had no signs or symptoms suggestive of HCM. This study, besides characterizing the spectrum of mutations in another childhood population, and revealing an even greater genetic heterogeneity than formerly recognized, may increase genotype-phenotype correlations, and thus may help to identify asymptomatic candidates for early preventive or therapeutic measures.

Twenty-four-hour blood pressure monitoring during treatment with extended-release felodipine versus slow-release nifedipine in elderly patients with mild to moderate hypertension: a randomized, double-blind, cross-over study

OBJECTIVE

This double-blind, placebo-controlled randomized study was designed to compare the antihypertensive effect and tolerability of extended-release felodipine and slow-release nifedipine retard in elderly hypertensive patients.

METHODS

Thirty patients of both sexes (mean age 71 years) with mild to moderate essential hypertension were recruited from our hypertension outpatient clinic. After a 2-week placebo period, felodipine extended-release (felodipine ER), 10 mg once daily, nifedipine slow-release retard (nifedipine SR), 20 mg twice daily or placebo were administered to each patient for 2 weeks according to a 3 x 3 latin-square design. At the end of each treatment period, the patients underwent 24-h noninvasive blood pressure monitoring.

RESULTS

All of the patients completed the trial and no serious adverse experience was reported. In comparison with placebo, felodipine and nifedipine decreased mean 24-h diastolic blood pressure by 6.7 and 4.3 mmHg, respectively, with no significant difference between the two drugs. Mean 24-h systolic blood pressure also decreased after felodipine and nifedipine, with no difference between the two drugs. Both drugs reduced blood pressure variability, lowering the 24-h mean standard deviation of mean hourly blood pressure values. The trough:peak ratio for felodipine was 80% for systolic and 75% for diastolic blood pressure.

CONCLUSION

Felodipine ER once daily lowers blood pressure in elderly hypertensives and is as effective as nifedipine SR twice daily. The high trough:peak ratio suggests that the dose and the between-dose interval of felodipine provides adequate therapeutic coverage.

The efficacy of controlled antibiotic release for prevention of polyethyleneterephthalate- (Dacron-) related infection in cardiovascular surgery

Infection of prostheses containing polyethyleneterephthalate (Dacron) remains a dreaded complication in cardiovascular surgery despite perioperative antibiotic (AB) prophylaxis. Dacron, which is widely applied as a fabric for manufacturing vascular prostheses and also the sewing rings of artificial heart valves, remains a source for infection once implanted in the body. In order to increase the AB concentration in Dacron, an experimental study including topical application of the gentamicin derivative EMD 46/217 and fibrin sealant (F) as AB carrier was initiated. In-vitro pretreatment of Dacron with the gentamicin derivative and F was followed by constant AB release for three weeks. In a subsequent animal study, four Dacron rings with different pretreatments were implanted in the descending aorta of ten pigs after direct contamination with 10 8 Staph. aureus solution. One ring was pretreated with the AB/F compound, a second ring with the AB alone. Ring 3 (no pretreatment) and ring 4 (F alone) served as controls. After one week, the Dacron rings and their corresponding implantation sites were asserved for measurement of AB content and for culture. The AB content of AB/F rings was 24.99 +/- 7.16 mug/g wet weight, while Dacron rings pretreated with the AB alone contained no measurable drug amounts, with the exception of one specimen (0.5 mug/g)(AB/F versus AB rings: P less than 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)

[Efficacy and tolerance of aniracetam in elderly patients with primary or secondary mental deterioration]

The study was carried out on 60 patients (mean age 69.9 +/- 10.3 years) suffering from slight-moderate brain pathology primary or secondary to vascular forms. Patients were treated with 1500 mg/day per os of Aniracetam or placebo. Drug efficiency evaluation was performed utilizing the following psychometric tests: Blessed Scale, figures repetition test, Benton test, Corsi test, Rey test, Pieron test, phrases construction test, verbal fluency test. They were carried out during basal visit after two and four month treatment. In Aniracetam treated group the score showed a significant improving during the first and second control. In placebo treated group no change statistically considerable happened in any test. Aniracetam has proved to be a useful drug in slight-moderate brain decay treatment of the elderly.

[The clinico-instrumental evaluation of the efficacy of picotamide in treating chronic obstructive arteriopathies of the lower extremities]

In 25 patients (19 males and 6 females) suffering from chronic arteriopathy of lower extremities at Fontaine stage II, the clinical efficacy of picotamide was investigated in double blind, cross over placebo-controlled study. Patients were assigned randomly to the treatment with placebo or picotamide (900 mg/die) for three months and, after 15 days of wash-out, to the treatment with picotamide or placebo for the same period. Painfree walking distance and ankle/arm systolic pressure ratio improved significantly only during picotamide treatment. Laboratory monitoring revealed a significant decrease in platelet aggregation and an increase of fibrinogen degradation products only during picotamide treatment. Three patients during picotamide treatment referred transient gastrointestinal discomfort (nausea, vomiting and diarrhoea); however in no case the treatment was suspended because of the appearance of these symptoms. These results indicate that picotamide is an effective drug in the management of chronic arteriopathy of lower extremities.

[The effects of slow-release verapamil in relation to plasma concentration in aged hypertensives. A study with continuous monitoring of arterial pressure and electrocardiogram]

Twenty-four hour ambulatory blood pressure and electrocardiographic monitoring (Oxford method) was carried out in baseline conditions and after 15 days of therapy with a once a day administration of 240 mg verapamil slow-release in 11 elderly hypertensive patients. The 24 hour electrocardiographic monitoring (but not the blood pressure monitoring) was also carried out after 30 days of therapy. High-pressure liquid chromatography plasma concentrations of verapamil and its metabolite norverapamil were compared with the blood pressure and electrocardiographic responses. Systolic and diastolic blood pressure were significantly reduced after 15 days of therapy without circadian rhythm modification; mean heart rate was reduced after 15 and 30 days and the P-Q interval prolonged. Peak verapamil and norverapamil plasma concentrations were observed 8 hours after administration; at the 25th hour, the concentrations were respectively 60.9% and 68.3% of peak value (139.5 +/- 95.4 ng/ml and 126.4 +/- 60.9 ng/ml). Plasma levels of verapamil and norverapamil significantly correlated with heart-rate decrease. No correlation was observed between drug concentrations and systolic and diastolic blood pressure. A first-degree atrioventricular block was observed in 3 patients during therapy. Supraventricular premature contractions showed a decrease after 15 and 30 days of therapy. Thus, once a day administration of verapamil slow release is an effective anti-hypertensive medication in elderly hypertensive patients. Caution should be exercised in patients with P-Q interval prolongation and sinus bradycardia.

Differences in blood pressure profile between young and elderly hypertensive patients

We studied 40 subjects, 20 under 60 yrs old (10 normotensive and 10 hypertensive) and 20 over 60 yrs old (10 normotensive and 10 hypertensive). Each patient underwent a 24-hour ambulatory blood pressure monitoring (8:00 a.m. to 8:00 a.m.), by a noninvasive method using an ICR 5300 apparatus. Systolic blood pressure was significantly higher on random measurement and during the daytime in the older patients. Although comparison of the other parameters did not reveal significant differences, we noted a tendency to higher systolic values among the older group, and higher diastolic values in the younger one. The variability of the values was slightly higher, although not significantly, among the older patients. In both groups random systolic measurements, and in the younger group diastolic values as well, were significantly higher than mean 24 hour values. The incidence of abnormal systolic BP values ranged from 18.8% to 100% (mean 60.2% +/- 28.9) in younger hypertensives, and from 54% to 100% (mean 76.5% +/- 14.4) in older patients. The incidence of abnormal diastolic BP values ranged from 64.5% to 100% (mean 80.4% +/- 15.6) in younger patients and from 47.2% to 96% (mean 67.8% +/- 15.8) in older patients. The correlation between mean systolic and diastolic values recorded from 8:00 to 10:00 a.m., and mean 24-hour values was significant in young hypertensives, while in the older group there was a significant correlation only for diastolic BP. The lack of significance for systolic values is probably due to a greater variability in systolic pressure in elderly subjects during the morning.(ABSTRACT TRUNCATED AT 250 WORDS)

[Papillary cystadenoma of the epididymis. Apropos of a rare case in a patient with grade III varicocele]

Primary tumours of the epididymis are rare and one of the rarest is papillary cysto-adenomas. For this reason, a case arising in a patient with Grade III varicocele seemed worth reporting. The report discusses the clinical case and describes the histological characteristics of the tumour.

A new primate model for the study of intravenous thrombotic potential and its modification

Advances in venous reconstruction have been limited by inherent venous thrombogenicity and the absence of a suitable prosthetic material for use in the venous system. We have designed an in vivo experimental model to evaluate early blood-material interactions within the venous system and to quantitate drug efficacy in the alteration of platelet function and fibrin deposition in the baboon. An 8F catheter was placed percutaneously in the femoral vein of an adult male baboon. Indium 111-labeled autogenous platelets or iodine 125-labeled human fibrinogen was infused before the introduction, into the inferior vena cava, of a linear array of 5 x 15 mm alternating Dacron and polytetrafluoroethylene samples attached to a benzalkonium-heparin-treated guide wire. At 60 or 120 minutes the samples were removed and a 1 ml aliquot of blood was drawn. The materials and blood samples were counted in a gamma well counter, and the material counts were normalized to the circulating label present in the 1 ml blood sample. The experiment was repeated after pretreatment with heparin, aspirin, or dextran. Whole blood clotting times and bleeding times were monitored. The results showed decreased platelet and fibrin deposition on polytetrafluoroethylene when compared with Dacron in the venous system. Aspirin, heparin, and dextran were all found to decrease platelet and fibrin deposition onto intravenously placed graft material samples (p less than 0.05, Student's t test). The data confirm the ability of the model to evaluate quantitatively anticoagulants, antiplatelet agents, and prospective graft materials for use in venous reconstructions.