In vitro activity of cadazolid against clinically relevant Clostridium difficile isolates and in an in vitro gut model of C. difficile infection

OBJECTIVES

We investigated the in vitro activity of cadazolid against 100 Clostridium difficile isolates and its efficacy in a simulated human gut model of C. difficile infection (CDI).

METHODS

MICs of cadazolid, metronidazole, vancomycin, moxifloxacin and linezolid were determined using agar incorporation for 100 C. difficile isolates, including 30 epidemic strains (ribotypes 027, 106 and 001) with reduced metronidazole susceptibility, 2 linezolid-resistant isolates and 2 moxifloxacin-resistant isolates. We evaluated the efficacy of two cadazolid dosing regimens (250 versus 750 mg/L twice daily for 7 days) to treat simulated CDI. Microflora populations, C. difficile total viable counts and spores, cytotoxin titres, possible emergence of cadazolid, linezolid or quinolone resistance, and antimicrobial concentrations were monitored throughout.

RESULTS

Cadazolid was active against all (including linezolid- and moxifloxacin-resistant) C. difficile strains (MIC90 0.125, range 0.03-0.25 mg/L). The cadazolid geometric mean MIC was 152-fold, 16-fold, 9-fold and 7-fold lower than those of moxifloxacin, linezolid, metronidazole and vancomycin, respectively. Both cadazolid dosing regimens rapidly reduced C. difficile viable counts and cytotoxin with no evidence of recurrence. Cadazolid levels persisted at 50-100-fold supra-MIC for 14 days post-dosing. Cadazolid inhibition of enumerated gut microflora was limited, with the exception of bifidobacteria; Bacteroides fragilis group and Lactobacillus spp. counts were unaffected. There was no evidence for selection of strains resistant to cadazolid, quinolones or linezolid.

CONCLUSIONS

Cadazolid activity was greater than other tested antimicrobials against 100 C. difficile strains. Cadazolid effectively treated simulated CDI in a gut model, with limited impact on the enumerated gut microflora and no signs of recurrence or emergence of resistance within the experimental timeframe.

ShearWave™ Elastography BE1 multinational breast study: additional SWE™ features support potential to downgrade BI-RADS®-3 lesions

PURPOSE

To determine the benefit of ShearWave™ Elastography (SWE™) in the ultrasound characterization of BI-RADS® 3 breast lesions in a diagnostic population.

MATERIALS AND METHODS

303 BI-RADS® 3 lesions (mean size: 13.2 mm, SD: 7.5 mm) from the multicenter BE1 prospective study population were analyzed: 201 (66%) had cytology or core biopsy, and the remaining 102 had a minimum follow-up of one year; 8 (2.6%) were malignant. 7 SWE features were evaluated with regard to their ability to downgrade benign BI-RADS® 3 masses. The performance of each SWE feature was assessed by evaluating the number of lesions correctly reclassified and the impact on cancer rates within the new BI-RADS® 3' lesion group.

RESULTS

No malignancies were found with an E-color "black to dark blue", which allowed the downgrading of 110/303 benign masses (p < 0.0001), with a non-significant increase in BI-RADS® 3' malignancy rate from 2.6% to 4.1%. E-max ≤ 20 kPa (2.6 m/s) was able to downgrade 48/303 (p < 0.0001) lesions with a lower increase in BI-RADS® 3' malignancy rate (3.1%). No other SWE features were useful for reclassifying benign BI-RADS® 3 lesions.

CONCLUSION

Applying simple reclassification rules, SWE assessment of the maximum stiffness of lesions allowed the downgrading of a sub-group of benign BI-RADS® 3 lesions. This was accompanied by a non-significant increase in the malignancy rate in the new BI-RADS® 3 class.

Erlotinib treatment in pretreated patients with non-small cell lung cancer: A Phase II study

Erlotinib is an oral, small-molecule targeting therapy that inhibits epidermal growth factor tyrosine kinase receptors. Erlotinib has been administered for the treatment of advanced pancreatic cancer and non-small cell lung cancer. In the present trial, erlotinib was administered as second-line monotherapy in pretreated patients with advanced non-small cell lung cancer. Our objectives were to determine response, survival and toxicity. Fifty-four patients pretreated with cisplatin or its analogue-based combinations were evaluated. The disease stage of the patients was IIIB and IV. Thirty-eight patients were male, 16 were female, the median age was 65 years, and the WHO performance status was 0-2. Twenty-five cases were adenocarcinomas, 19 squamous cell carcinomas and 10 were undifferentiated. Erlotinib was administered at a dose of 150 mg daily. In case of intolerable adverse reactions, the dose was either reduced to 100 mg daily or treatment was interrupted for a maximum of two weeks. A partial response was observed in 10 (18.52%) and stable disease in 40 (74.07%) patients. The median time to disease progression was 3 months (95% CI 1.7-10.3), and the median survival was 6 months. Concerning toxicity, 53 patients (98.15%) developed a grade 1-2 skin rash, and 1 (1.85%) grade 3. Diarrhea occurred in 9 (16.67%) patients, nausea and vomiting in 4 (7.41%) and gastritis in 2 (3.70%). The majority of patients tolerated the erlotinib treatment. Of note were the 18.52% response rate and 74.07% stable disease.

Serious hematologic complications following erlotinib treatment

BACKGROUND

Erlotinib is an oral, small-molecule targeting therapy which inhibits epidermal growth factor tyrosine kinase receptors. Erlotinib has been administered for the treatment of advanced pancreatic cancer and non-small cell lung cancer.

PATIENTS AND METHODS

In the present report, unusual hematologic complications were detected after erlotinib was administered as second-line monotherapy in pretreated patients with advanced non-small cell lung cancer. Four patients pre-treated with cisplatin or its analog-based combinations, were evaluated. Erlotinib was given at a dose of 150 mg daily. In cases of intolerable adverse reactions, the dose was either reduced to 100 mg daily or treatment was interrupted for a maximum of two weeks.

RESULTS

Serious hematologic toxicity (or complications) developed in these 4 patients after 4-8.5 months of treatment. Two patients developed leukemias (AML, CML) and two, myelodysplastic syndrome.

CONCLUSION

Whether or not these hematologic complications were related to erlotinib treatment is comprehensively discussed.

Vacuum-assisted biopsies under MR guidance: results of 72 procedures

OBJECTIVE

To investigate the clinical accuracy of magnetic resonance imaging-guided breast vacuum-assisted biopsy (MR-VAB).

METHODS

Of 97 scheduled MR-VAB for single MRI lesions (negative second-look sonography) categorised as BI-RADS 4 or 5, 4 were cancelled (undetected lesion = 2, technical problems = 2). Twenty-one patients lost to follow-up were excluded.

RESULTS

Twenty-three patients (median age 51 years) were at high risk (BRCA1 = 11, BRCA2 = 7, familial risk = 5), 23 had a suspected local recurrence of breast cancer. Seventy-two imaged lesions (focus = 1, mass enhancement = 32, non-mass-like enhancement = 39) were targeted with a 10-gauge VAB probe using MRI guidance, with a median of 18 specimens per lesion (median procedural time 72 min, range 50-131 min) followed by clip placement. In the case of benignity, MRI follow-up was performed (19 patients, median 389 days, range 33-1,592) or mammography (3 patients, median 420 days, range 372-1,354). According to histopathology results, 29 lesions were benign, 10 were high-risk (papillary = 2, radial scar = 1, atypical epithelial hyperplasia = 7) and 33 malignant (ductal carcinoma in situ = 8, invasive cancers = 25). Three false negative results and 3 complications occurred (1 malaise, 1 skin defect, 1 infection).

CONCLUSION

MRI-guided VAB represents an accurate tool for the histological diagnosis of lesions visible only at MRI.

Contribution of BRCA1 germ-line mutations to breast cancer in Greece: a hospital-based study of 987 unselected breast cancer cases

Background:

In most Western populations, 5–10% of all breast cancer cases can be attributed to major genetic factors such as predisposing mutations in BRCA1 and BRCA2, with early-onset cases generally considered as an indicator of genetic susceptibility. Specific BRCA1 and BRCA2 mutations or different mutation frequencies have been identified in specific populations and ethnic groups. Previous studies in Greek breast and/or ovarian cancer patients with family history have shown that four specific BRCA1 mutations, c.5266dupC, G1738R, and two large genomic rearrangements involving deletions of exons 20 and 24, have a prominent function in the population's BRCA1 and BRCA2 mutation spectrum.

Methods:

To estimate the frequency of the above mutations in unselected Greek breast cancer women, we screened 987 unselected cases independently of their family history, collected from major Greek hospitals.

RESULTS: Of the 987 patients, 26 (2.6%) were found to carry one of the above mutations in the BRCA1 gene: 13 carried the c.5266dupC mutation (1.3%), 6 carried the exon 24 deletion (0.6%), 3 carried the exon 20 deletion (0.3%), and 4 carried the G1738R mutation (0.4%). Among 140 patients with early-onset breast cancer (<40 years), 14 carried one of the four mutations (10.0%).

Conclusion:

These results suggest that a low-cost genetic screening for only the four prominent BRCA1 mutations may be advisable to all early-onset breast cancer patients of Greek origin.

Lipoplatin plus gemcitabine versus cisplatin plus gemcitabine in NSCLC: Preliminary results of a phase III trial

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Background: Lipoplatin is a liposomal formulation of cisplatin, designed to reduce its adverse reactions without reducing efficacy. Its nanoparticles evade immune surveillance and extravasate preferentially into tumors inducing tumor cell apoptosis; lipoplatin may also act as antiangiogenesis factor. This is the initial report of a randomized, multicenter, phase III trial comparing the two drugs. Methods: Eligibility criteria included confirmed diagnosis of inoperable/metastatic NSCLC, no previous chemotherapy, WHO PS 0–1, adequate end-organ function. Patients received Lipoplatin 120 mg/m2 D1,8,15 or cisplatin 100 mg/m2 D1, combined with gemcitabine 1,000 mg/m2 D1,8, in 3-week cycles, with disease evaluation after 3 and 6 cycles. Primary endpoints are overall survival and toxicity, with Response Rates, PFS and QOL also being evaluated. Results: 59 patients have been treated, 33 with lipoplatin and 26 with cisplatin; 17 have completed treatment. 2 lipoplatin patients had a hypersensitivity reaction during the first infusion. There were no grade 4 toxicities. Grade 3 toxicities were observed in <5% of the patients and were comparable for the two groups, except neutropenia (3% for lipoplatin, 15% for cisplatin). Main grade 1–2 toxicities were anemia (93% vs 88%), leucopenia (51% vs 38%), neutropenia (45% vs 30%), thrombocytopenia (58% vs 31%), hepatotoxicity (38% vs 46%), nausea/vomiting (13% vs 35%), asthenia (31% vs 30%) and anorexia (32% vs 34%). Concerning nephrotoxicity, grade 2 was reported in only 6% of lipoplatin patients vs 19% in cisplatin, although lipoplatin was administered without pre-hydration as a 6-hour infusion. Neurotoxicity was also markedly less in lipoplatin. So far, 32 patients have been assessed for response, 16 in each group; 4 partial responses have been reported in each group. However, difference has been observed in stable disease (23% in lipoplatin vs 12% in cisplatin) as well as progressive disease (16% vs 35%). Conclusions: Preliminary results show that lipoplatin may have a better safety and therapeutic profile than cisplatin, when combined with gemcitabine, in advanced NSCLC. Particularly important might be its significantly lower neuro- and nephro-toxicity and its administration on an outpatients basis.

No significant financial relationships to disclose.

Breast radiological cases: training with BIRADS® classification

The American College of Radiology has established guidelines for outcomes monitoring known as the Breast Imaging Reporting and Data System. The last edition of the BIRADS classification includes mammography, but also ultrasonography and MRI. Radiologists must be used to the BIRADS lexicon and the BIRADS assessment, in order to clarify mammography reports and to facilitate communication with the other physicians. This work is a training on 20 mammography cases to be familiar with the BIRADS classification.