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Conrad Timon

Publications and source records attributed to Conrad Timon.

13 recordsLinked to original sources
PubMed2007

Low-level genomic instability is a feature of papillary thyroid carcinoma: an array comparative genomic hybridization study of laser capture microdissected papillary thyroid carcinoma tumors and clonal cell lines.

CONTEXT: Previous chromosomal comparative genomic hybridization (CGH) studies of papillary thyroid carcinoma (PTC) have demonstrated a low prevalence of aberrations, with the majority of tumors showing no evidence of chromosomal instability. The technique of CGH can be optimized, however, using array CGH and laser capture microdissection to ensure pure cell populations for analysis. OBJECTIVE: To assess PTC using array CGH applied to laser capture microdissected tumor cells and pure cell cultures. DESIGN: Well-characterized PTC (known ret/PTC and BRAF mutation status), including samples from 5 tumors with classic morphology, 3 follicular variant tumors, and 3 clonal PTC cell lines, were analyzed. RESULTS: Copy gain and loss occurred in all of the tumor cases and cell lines examined. The most common recurrent aberrations involved gains on chromosomes 1, 5, 7, 11, 15, 17, and 22, with recurrent deletions occurring on chromosomes 4, 18, and 19. Analysis of the data from the 8 tumor samples showed that amplifications of TP73 (1p36.33), SNRPN (15q12), and PDGFB (22q13.1) occurred exclusively in tumors with a wild type BRAF. CONCLUSIONS: This study shows a higher prevalence of aberrations detected using array CGH allied to laser capture microdissection than previously described in the literature, and it appears that the combination of laser capture microdissection and arrayed clones optimizes studies utilizing CGH. Copy gain of PDGFB occurs in a subset of tumors showing no evidence of mutated BRAF or rearranged ret, suggesting that copy gain of PDGFB may underlie the increased expression of platelet-derived growth factor described recently in the literature.

Adult↗
PubMed2006

Distinct array comparative genomic hybridization profiles in oral squamous cell carcinoma occurring in young patients.

BACKGROUND: Oral cancer typically affects smokers older than 50 years of age. Recently, however, a marked increase in the number of patients 40 years old and younger, many with no history of tobacco smoking, has been noted. Studies in this age group have so far been restricted to genomic areas well recognized as abnormal in typical patients with oral cancer. The aim of this study was to assess genomic aberrations in oral cancer, using comparative genomic hybridization (CGH) microarray technology, and to compare the genomic aberration profile of patients older than 40 years old with those 40 years old and younger. METHODS: Tumor samples from 20 patients with oral cancer (age range, 21-78; 10 smokers and 10 nonsmokers) were laser microdissected, and array CGH was used to identify genomic imbalances in these two cohorts. RESULTS: The older cohort showed high numbers of gains and losses in contrast to very few copy number changes in the younger nonsmoker cohort. In concurrence with the literature, tumors from the older cohort manifested deletions involving 3p and 9p21 and gains involving 3q, 5q, 7p, 8q, 11q, and 20q. The younger group, particularly the nonsmokers, showed very few changes overall, and the aberrations were not in the sites classically associated with oral cancer. Deletion of CDKN2A (p16) was completely absent in the younger group but was present in 50% of the older cohort. CONCLUSIONS: We have demonstrated that there is far less genomic instability in young nonsmokers with oral cancer than found in typical patients with oral cancer. These observations indicate that oral cancer presenting at a younger age, particularly in nonsmokers, has a genomic profile different from the classically described oral cancer.

Adult↗
PubMed2006

Minimal incision for open thyroidectomy.

OBJECTIVES: To establish the incision length for thyroid surgery that optimizes access and cosmesis. STUDY DESIGN AND SETTING: Prospective study from January 2003 to June 2004. All thyroidectomies were included. Exclusion criteria were concomitant neck dissections, previous surgery, and those performed endoscopically. The first 40 cases were attempted through a 5 cm incision and the second 40 through a 4 cm incision. METHODS: In both groups, the size of the incision was compared with the thyroid's weight and histology. RESULTS: Two subtotal, 22 total, and 56 hemithyroidectomies were performed. In the first group, median gland weight was 39.5 gm and 62.5% of these were removed through a 5 cm incision. In the second group, median gland weight was 34 gm and 75% were removed through a 4 cm incision. CONCLUSION: A 4 cm incision provides adequate access for the majority of thyroidectomies in our cohort. SIGNIFICANCE: The minimal incision thyroidectomy is a useful addition to the thyroid surgeon's armamentarium. EBM RATING: B-3b.

Adult↗
PubMed2005

Use of an intra-operative nerve stimulator in identifying the hypoglossal nerve.

Previously, the hypoglossal nerve has not undergone intra-operative monitoring during neck operations in which the nerve is at risk. As society becomes increasingly litigious, this may change. This study describes the technique and the microvoltages used in 10 patients for intra-operative stimulation of the hypoglossal nerve with the Magstim nerve stimulator. We confirm that the technique is possible, simple and safe, with minimal disturbance to the patient, anaesthetist and surgeon.

Electric Stimulation↗
PubMed2005

Unexpected findings in neck dissection for squamous cell carcinoma: incidence and implications.

BACKGROUND: During the pathologic examination of neck dissections, unexpected pathologic findings may occasionally be encountered. These pathologic findings may simulate malignant disease and/or have implications on the already complicated management of patients with head and neck cancer. METHODS: We retrospectively reviewed 202 consecutive patients with a preoperative diagnosis of squamous cell carcinoma (SCC), who underwent 307 neck dissections performed by a single surgeon and examined by a single pathologist. RESULTS: Ten patients had an unexpected finding. These included metastatic papillary thyroid carcinoma, leukemia, lymphoma, Warthin's tumor, and tuberculosis. Two of three patients with benign-appearing thyroid tissue within lymph nodes received no further treatment, and both remained well beyond 6 years. Four patients succumbed to SCC; none died from the incidentally discovered pathologic findings. CONCLUSIONS: Unexpected pathologic findings may be present in more than 3% of neck dissections. Although this is usually indolent, with the underlying SCC remaining the main prognostic determinate, it may significantly complicate postoperative management.

Adenolymphoma↗
PubMed2005

Informed consent: a patients' perspective.

The medico-legal issues surrounding informed consent are highly topical and contentious. Current attitudes to consent emphasize the high level of 'good medical practice' expected by a 'reasonable patient/parent'. The authors' objectives were to assess the levels of knowledge and information expected by patients and parents, prior to signing consent forms for a surgical procedure. Each patient or parent was asked a series of questions prior to signing a consent form. Answers were recorded on a standard questionnaire. More than 80 per cent of respondents were happy with the information provided in out-patients, however, over half of these could not list even one complication of their operation. Two-thirds of those surveyed sought information elsewhere, while over half expected to be informed of all known complications, even if the rate of complications was less than one per cent. In conclusion, the information provided by surgeons might not meet the expectations of today's informed patients.

Attitude to Health↗
PubMed2004

Linear IgA disease presenting as desquamative gingivitis: a pattern poorly recognized in medicine.

Linear IgA disease is a subepidermal blistering disorder of unknown cause. Along with dermatologic blistering, other manifestations include oral ulceration and desquamative gingivitis. We present a case of linear IgA disease that manifested simply as oropharyngeal ulceration and desquamative gingivitis, resulting in considerable delay in diagnosis and treatment. This article (1) highlights the difficulties of diagnosing linear IgA disease when the predominant presenting features are mucosal and (2) reviews the current literature regarding linear IgA disease.

Autoimmune Diseases↗
PubMed2004

Role of CO2 laser in the management of obstructive ectopic lingual thyroids.

Ectopic lingual thyroid glands may occasionally undergo massive hypertrophy and be a source of airway obstruction. Securing the airway prior to surgery in such cases may be difficult. In the present paper, we report on two cases of obstructive ectopic lingual thyroids which were successfully managed endoscopically using CO(2) laser. The use of CO(2) laser for removal of ectopic lingual thyroid tissue offers advantages over traditional surgical techniques. In our opinion, removal of an appropriate amount of gland to secure an adequate airway is all that is required in most cases.

Adult↗
PubMed2002

The node-negative neck: accuracy of clinical intraoperative lymph node assessment for metastatic disease in head and neck cancer.

OBJECTIVES/HYPOTHESIS: Often, the type of neck dissection performed in patients with head and neck malignancy is finally determined by intraoperative assessment of clinically suspect lymph nodes by frozen section. This prospective study aimed to assess the accuracy of clinical intraoperative lymph node assessment and therefore to examine validity of the underlying assumption that the surgeon can consistently identify nodes that contain metastatic tumor. We also aimed to assess whether gross morphological characteristics of the lymph nodes examined could be correlated with nodal status and therefore used to predict those nodes containing metastatic disease. STUDY DESIGN: A prospective study assessing the accuracy of clinical intraoperative lymph node assessment in the node-negative neck. METHODS: Forty-six neck dissections from 34 patients with head and neck cancer were prospectively examined intraoperatively by a single surgeon. All obvious nodes were clinically assessed, morphologically described, and subsequently correlated with pathological findings. RESULTS: Sixty palpable nodes were identified in 32 neck dissections. They were clinically categorized as malignant or suspect (22) or benign (38). Pathological examination revealed a false-positive rate of 30% and a false-negative rate of 44%. The sensitivity of intraoperative lymph node assessment was 56%, and the specificity was 70%. Apart from "infiltration," morphological characteristics could not be correlated with nodal status. In the 14 neck dissections with no obviously palpable lymph nodes, 4 (29%) were positive for metastatic disease. CONCLUSIONS: In the node-negative neck, intraoperative assessment does not seem to improve the accuracy of staging. The only parameter of benefit and correlating with metastatic disease is clinical evidence of infiltration. The assumption that frozen section is a good determinate for selection of type of neck dissection is questionable. If selective neck dissection is not found to be therapeutic, its use leads to over-reliance on other therapeutic treatment such as postoperative radiotherapy, depriving the patient of a potential useful treatment modality in cases of locoregional recurrence.

Carcinoma, Squamous Cell↗
PubMed2002

Sleep apnoea of unusual origin.

A 72-year-old man presented with a history of progressive sleep apnoea. The cause was a large superior laryngeal nerve schwannoma arising in the left parapharyngeal space. This had a ball-valve effect on the laryngeal inlet. Superior laryngeal nerve schwannomas are very rare. No documented case has presented with obstructive sleep apnoea before.

Aged↗