Exome sequencing in 32 patients with anophthalmia/microphthalmia and developmental eye defects

Anophthalmia/microphthalmia (A/M) is a genetically heterogeneous birth defect for which the etiology is unknown in more than 50% of patients. We used exome sequencing with the ACE Exome(TM) (Personalis, Inc; 18 cases) and UCSF Genomics Core (21 cases) to sequence 28 patients with A/M and four patients with varied developmental eye defects. In the 28 patients with A/M, we identified de novo mutations in three patients (OTX2, p.(Gln91His), RARB, p.Arg387Cys and GDF6, p.Ala249Glu) and inherited mutations in STRA6 in two patients. In patients with developmental eye defects, a female with cataracts and cardiomyopathy had a de novo COL4A1 mutation, p.(Gly773Arg), expanding the phenotype associated with COL4A1 to include cardiomyopathy. A male with a chorioretinal defect, microcephaly, seizures and sensorineural deafness had two PNPT1 mutations, p.(Ala507Ser) and c.401-1G>A, and we describe eye defects associated with this gene for the first time. Exome sequencing was efficient for identifying mutations in pathogenic genes for which there is no clinical testing available and for identifying cases that expand phenotypic spectra, such as the PNPT1 and COL4A1-associated disorders described here.

Oral mucositis is associated with increased resource use among patients receiving treatment for cancers of the head and neck

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Background: Oral mucositis (OM) is the oral manifestation of mucosal injury (MUI), and is a common, bothersome, and treatment-interrupting toxicity of chemoradiation therapy for squamous cell cancers (SCC) of the head and neck. Retrospective studies have reported that OM increases healthcare resource use. We present interim results of an international, multicenter, prospective study undertaken to characterize the clinical and economic burden of OM in patients with cancers of the oral cavity (OC), oropharynx (OP), larynx (L) and hypopharynx (HP). Methods: Patients (pts) with histologically proven SCC of the designated anatomical sites, whose planned treatment included full-cycle conventional or intensity modulated (IM) radiation therapy (RT) with or without chemotherapy, were enrolled at least one week prior to the start of treatment. Pts completed the Oral Mucositis Daily Questionnaire (OMDQ), a validated questionnaire developed to document patient-reported symptoms of OM and MUI including mouth and throat soreness (MTS), at baseline and daily throughout RT. MTS was assessed using a 5-point numeric rating scale, ranging from 0 (“no soreness”) to 4 (“extreme soreness”). Results: Of the first 61 pts to complete RT, 72% had cancers of the OC or OP, 49% received IMRT with concomitant chemotherapy, and 68% were male. 95% of pts reported OM symptoms (MTS>0); 80% had one or more scores =2. Pts with OC or OP cancers reported more symptoms than those with L or HP tumors (mean maximum score: 3.3 vs 2.8; p= 0.12). MTS scores were positively related to levels of resource use. Conclusions: Symptoms of radiation-induced OM are positively correlated with levels of resource utilization in patients with head and neck cancers.

No significant financial relationships to disclose.

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Sequence analysis of the mismatch repair gene hMSH6 in the germline of patients with familial and sporadic colorectal cancer

To evaluate the involvement of hMSH6 in colorectal cancer, the complete coding sequence and flanking intron regions of the gene were analyzed by DNA sequencing in 10 patients fulfilling Bethesda Guidelines for colorectal tumors and 10 patients with sporadic colorectal carcinoma. In addition, 10 mono- and 10 dinucleotide repeat markers were analyzed for microsatellite instability. A protein-truncating T insertion at codon 218 was identified in the index person of a hereditary non-polyposis colorectal cancer (HNPCC)-like kindred and was accompanied by a somatic T deletion in the tumor. The tumor of this patient was positive for mono- but negative for dinucleotide repeat instability and lacked allelic losses at loci frequently affected in colorectal carcinomas. A novel amino acid change, F340S, was found in a patient with sporadic colon and breast cancer and leukemia but was not detected in 246 chromosomes from healthy anonymous blood donors. In addition, we describe 2 silent and 15 intronic sequence variants not previously reported. Although the frequency is low, we present further evidence for hMSH6 germline mutations that predispose patients to HNPCC-like phenotypes and suggest that mono- and dinucleotide repeat instability testing may be useful for distinguishing between individuals harboring an hMSH2 or hMLH1 mutation and a mutation of the hMSH6 gene.

Sequence analysis of the mismatch repair gene hMSH6 in the germline of patients with familial and sporadic colorectal cancer

To evaluate the involvement of hMSH6 in colorectal cancer, the complete coding sequence and flanking intron regions of the gene were analyzed by DNA sequencing in 10 patients fulfilling Bethesda Guidelines for colorectal tumors and 10 patients with sporadic colorectal carcinoma. In addition, 10 mono- and 10 dinucleotide repeat markers were analyzed for microsatellite instability. A protein-truncating T insertion at codon 218 was identified in the index person of a hereditary non-polyposis colorectal cancer (HNPCC)-like kindred and was accompanied by a somatic T deletion in the tumor. The tumor of this patient was positive for mono- but negative for dinucleotide repeat instability and lacked allelic losses at loci frequently affected in colorectal carcinomas. A novel amino acid change, F340S, was found in a patient with sporadic colon and breast cancer and leukemia but was not detected in 246 chromosomes from healthy anonymous blood donors. In addition, we describe 2 silent and 15 intronic sequence variants not previously reported. Although the frequency is low, we present further evidence for hMSH6 germline mutations that predispose patients to HNPCC-like phenotypes and suggest that mono- and dinucleotide repeat instability testing may be useful for distinguishing between individuals harboring an hMSH2 or hMLH1 mutation and a mutation of the hMSH6 gene.

Thrombolytic treatment and balloon angioplasty in chronic occlusion of the aortic bifurcation

OBJECTIVE

To evaluate nonsurgical alternatives in reopening chronically occluded aortic bifurcation.

DESIGN

Uncontrolled randomized study.

SETTING

University-affiliated referral center for vascular diseases.

PATIENTS

Twenty-five of 39 consecutive patients with chronic aortoiliac disease including a totally occluded aortic bifurcation were found to be acceptable candidates for an aortobifemoral prosthetic graft.

INTERVENTION

Patients were randomly assigned to receive either streptokinase or urokinase or recombinant tissue-type plasminogen activator (rt-PA). In cases of successful thrombolysis and residual obstructions, subsequent balloon angioplasty was attempted. Prosthetic bypass grafting was done if thrombolytic treatment and balloon angioplasty failed.

RESULTS

Complete lysis was achieved in 5 of 25 patients (20%). In 10 (40%) patients, lysis showed residual obstructions, which were reopened mechanically in 8 patients; 2 patients had extra-anatomical bypass grafts. Ten patients (40%) without thrombolysis had surgical aortobifemoral bypass grafts. Overall, recanalization and clinical improvement were achieved in 13 of 25 patients (52%) by thrombolytic therapy and subsequent balloon angioplasty. The recanalization rate did not differ among the different thrombolytic drugs. However, rt-PA therapy resulted in reopening after 4 days of treatment; streptokinase, after 6 days; and urokinase, after 9 days (P < 0.005). No major complications or deaths occurred.

CONCLUSION

Thrombolytic treatment followed by balloon angioplasty may help avoid the need for aorto-bifemoral prosthetic bypass grafting in more than 50% of patients with chronic aortoiliac disease.

Surface coil proton MR imaging at 2 T

We describe the design and application of surface coils for magnetic resonance (MR) imaging at high resonance frequencies (85 MHz). Circular, rectangular-frame, and reflector-type surface coils were used in the transmit-and-receive mode. With these coils, the required radio frequency power is reduced by factors of two up to 100 with respect to head and body coils. With the small, circular coils, high-resolution images of a small region of interest can be obtained that are free of foldback and motion artifacts originating outside the field of interest. With the rectangular-frame and reflector coils, large fields of view are also accessible. As examples of applications, single- and multiple-section images of the eye, knee, head and shoulder, and spinal cord are provided.

MR imaging using stimulated echoes (STEAM)

The introduction of STEAM (stimulated echo acquisition mode) magnetic resonance (MR) sequences provides access to a variety of MR parameters. T1-weighted and calculated T1 proton MR images of the head of healthy volunteers and a patient with an astrocytoma are presented. MR examinations were performed with a 2.0-T whole-body system. The STEAM T1 method can be used to characterize multiexponential relaxation behavior, to evaluate T1 relaxation times, and to improve the T1 contrast within MR images. Both the measuring time and the spatial resolution are the same as for a conventional image.

Dual-energy Compton scatter tomography

A dual-energy Compton scatter imaging technique, analogous to that used in computed tomography and conventional radiography, has been explored. It is shown that this technique allows the photoelectric component of the attenuation factors for the primary and scattered radiations to be derived. Compton scatter images of the ear, corrected for photo-attenuation using dual energy, have been obtained with a novel Compton scatter scanner (Comscan) and are presented here. In addition, dual-energy Compton scatter imaging allows photo-effect slice images to be obtained which are a useful extension to the customary Compton images. The application of dual-energy Compton scatter to imaging bony structures and densitometry is illustrated.