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N F Quenville

Publications and source records attributed to N F Quenville.

At least 19 recordsLinked to original sources
PubMed1995

Detection of squamous neoplasia by fluorescence imaging comparing porfimer sodium fluorescence to tissue autofluorescence in the hamster cheek-pouch model.

BACKGROUND: Early neoplastic changes in the oral cavity may be difficult to detect. Fluorescence imaging using porphyrin-derived drugs has been used to enhance detection of neoplasia. Autofluorescence has also been used for this purpose. This paper compares autofluorescence to porfimer sodium-induced fluorescence in the detection of neoplasia in the hamster cheek-pouch model. MATERIALS AND METHODS: Neoplasia was induced in the hamster cheek pouch by the application of 9,10-dimethyl-1,2-benzanthracene. Animals were imaged either with injection of drug (porfimer sodium) or without drug (autofluorescence). Imaging was carried out using a laser-induced fluorescence detection system. Biopsies were performed on imaged sections and histologic grades were assigned. RESULTS: Porfimer sodium fluorescence provided 100% sensitivity and specificity in detection of neoplasia. The sensitivity and specificity with autofluorescence was 76% and 83%, respectively. CONCLUSIONS: Autofluorescence provides an accurate means of detecting early neoplastic changes in the hamster cheek-pouch model; however, porfimer sodium imaging does improve detection rates.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1993

Photodynamic therapy of squamous cell carcinoma. An evaluation of a new photosensitizing agent, benzoporphyrin derivative and new photoimmunoconjugate.

Photodynamic therapy for cancer depends on the relatively selective distribution of photosensitizing agents to malignant as compared with normal tissues, rendering the malignant cells more susceptible to light-mediated damage. Photodynamic therapy has been used with only moderate success to date. The purpose of this study was to compare a new photosensitizing agent, benzoporphyrin derivative (BPD), to the standard agent presently in use, photofrin II, in a hamster cheek pouch model of squamous cell carcinoma. As well we have investigated the potential of using a tumour-specific monoclonal antibody-BPD conjugate to improve the tumour localizing properties of BPD. Treatment consisted of photodynamic therapy with either photofrin II, BPD, or a tumour-specific anti-epidermal growth factor receptor-BPD conjugate. Control groups of light alone, anti-EGFr, tumour non-specific MoAb, and tumour non-specific MoAb-BPD conjugate were included with the contralateral cheek pouch of each animal acting as a dark control. An assessment of differential delivery of BPD to tumour and to normal mucosa was undertaken using a spectrophotometric assay. Parametric statistical analysis included Student's t-tests and linear regression while non-parametric analysis was undertaken using Fisher's exact test. Animals receiving BPD alone demonstrated tumour-to-tissue levels of approximately 2:1 while animals receiving the tumour-specific anti-EGFr-BPD conjugate had significantly better tumour:tissue ratios of 26:1 (P < 0.005). Animals treated with photofrin II had a 1 month cancer-free survival of 27% while animals treated with BPD had an improved survival of 67% (P = 0.03). The group treated with the tumour-specific anti-EGFr-BPD conjugate at a twentieth the total dose of BPD had an 80% 1 month cancer-free survival which was not statistically different from the group treated with BPD alone. Benzoporphyrin appears to be a more effective photosensitizing agent than Photofrin II and its tumour selectivity can be improved using a tumour specific monoclonal antibody conjugate.

Animals↗
PubMed1992

Prognostic markers of colorectal cancer: an evaluation of DNA content, epidermal growth factor receptor, and Ki-67.

Between January 1989 and August 1991, 62 patients undergoing resection for colorectal adenocarcinoma were assessed in a prospective fashion on the basis of various tumor characteristics that are thought to indicate prognosis. Parameters measured included epidermal growth factor receptor (EGFr) expression, a cell membrane receptor known to be overexpressed in a variety of tumors, Ki-67, a monoclonal antibody marker of cell proliferation, as well as flow cytometry and standard histologic examination. Statistical analysis included chi square with Yates correction when appropriate, Wilcoxon W, and multivariate logistic regression. EGFr positive tumors were associated with worse Dukes' stage (27% of EGFr negative tumors were Dukes' C or D vs. 58% of EGFr positive tumors, P = 0.03), as well as more aneuploid characteristics by flow cytometry (48% EGFr negative = aneuploid vs. 82% EGFr positive = aneuploid, P = 0.01). Lymphatic invasion was more frequent in EGFr positive tumors (P = 0.03). These factors proved to be independent of each other by multivariate analysis. Ki-67 did not correlate with any of the measured parameters and was of extremely limited use in the evaluation of the study population. Multivariate analysis indicated that aneuploid tumors were associated with worse Dukes' stage than diploid tumors. Histologic parameters such as lymphatic and vascular invasion as well as histologic grade are compared to the other parameters involved with prognosis.

Adenocarcinoma↗
PubMed1992

Case report 708: Metastasis of renal cell carcinoma to skeletal muscle (right trapezius).

A patient is described who presented with a painful soft-tissue mass in the region of the right shoulder 10 months following nephrectomy for carcinoma. This mass proved to be a metastasis to skeletal muscle. A full metastatic work-up demonstrated no other detectable lesions. Metastases to skeletal muscle are rare, regardless of the site of origin, and their true incidence is difficult to determine since they rarely present clinically and are not routinely searched for, even on autopsy.

Carcinoma, Renal Cell↗
PubMed1992

Detection of squamous cell cancer and pre-cancerous lesions by imaging of tissue autofluorescence in the hamster cheek pouch model.

Early detection of invasive and pre-invasive neoplasms of the aerodigestive tract will ultimately improve the management of patients with these lesions. This paper describes the use of quantitative fluorescence imaging of early squamous cell carcinomas in an animal model. Dysplasia, carcinoma in situ and invasive cancers were imaged exploiting tumour autofluorescence. Mapped biopsies were obtained from areas imaged determining a sensitivity of 100% and specificity of 80%. Autofluorescence imaging is an excellent method of detecting neoplasms of the aerodigestive tract.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1992

Correlation of epidermal growth factor receptor and c-erbB2 oncogene product to known prognostic indicators of colorectal cancer.

Both epidermal growth factor receptor (EGFr) and the oncogene product of c-erbB2 have been shown to be expressed by human malignancies, and in some cases to relate to clinical outcomes. This study investigates the correlation between the presence of these receptor proteins and known prognostic indicators of colorectal cancer. Indirect immunoperoxidase staining of 32 freshly frozen surgical specimens revealed an overall expression of EGFr and c-erbB2 of 43% and 38%, respectively. A significantly higher rate of EGFr expression was found in tumours of more advanced stage (Dukes C and D), poor differentiation and those exhibiting vascular and lymphatic invasion. The presence of the c-erbB2 protein did not correlate with any of these variables. Expression of these molecules appeared to be independent and positive staining for both receptors occurred in only 19% of cases. EGFr may play a future role as a prognostic tool in colorectal cancer.

Adult↗
PubMed1990

The intercostal pathway for biliary lithotripsy: an evaluation.

Intercostal biliary extracorporeal shock wave lithotripsy (BESWL), an alternative method for targeting retrocostal gallbladders, was evaluated in a three-stage study. First, 10 pigs (three with implanted gallstones) underwent BESWL at different, increasing shock wave pressures. Histologic studies were done in seven animals and showed no macroscopic abnormalities. Microscopically, two pigs had 1-3-mm blood collections in the shock wave path. Next, 11 patients in whom subcostal BESWL was not feasible underwent intercostal BESWL. One patient complained of contact-site tenderness after BESWL, which resolved spontaneously. Transient elevations of aspartate aminotransferase occurred in two asymptomatic patients. Finally, both pathways were evaluated in 22 consecutive patients. Intercostal BESWL was the method of choice in only two patients. In each stage of the study all intercostally targeted gallstones fragmented. It is concluded that the intercostal pathway is a valid alternative whenever subcostal BESWL proves unsatisfactory.

Animals↗
PubMed1989

Gallbladder ablation through radiologic intervention: an experimental alternative to cholecystectomy.

Twenty pigs underwent (a) cystic duct occlusion by means of fluoroscopically guided transcatheter endoluminal bipolar radio-frequency (RF) electrocoagulation and (b) gallbladder sclerotherapy with one of two different regimens of ethanol and sodium tetradecyl-sulfate (STS). Serum ethanol levels and hepatic enzyme tests showed no acute toxicity. Postmortem histologic studies showed that the bile ducts beyond the occlusion site remained entirely unaffected in all animals. In three of four animals followed up for 2 weeks, the sclerosants induced necrosis of the gallbladder mucosa, but the adjacent liver, serosa, and blood vessels remained intact. In 13 of 16 animals followed up for 8 weeks, the gallbladder lumen was obliterated by fibrous scar tissue. In the animals treated with 95% ethanol and 3% STS, the gallbladder mucosa was necrotic in all areas after 2 weeks (two of two animals) and eradicated completely after 8 weeks (six of eight animals); the other regimen (70% ethanol plus 1% STS) was somewhat less effective. In this study, the combination of RF-mediated cystic duct occlusion and gallbladder sclerotherapy with ethanol and STS permitted gallbladder ablation in swine without toxic side effects.

Animals↗
PubMed1989

Soft-tissue effects of biliary extracorporeal shockwave lithotripsy in swine.

This study investigates the soft-tissue effects of biliary extracorporeal shockwave lithotripsy (BESWL) using a recently developed lithotripter, which consists of an electromagnetic shockwave generator and an integrated ultrasonic targeting system. Sixteen swine, evenly divided into four groups, underwent BESWL. One group had one BESWL session targeted on the gallbladder and another group had two BESWL sessions targeted on the gallbladder. The third group had one BESWL session targeted on implanted gallbladder stones and the fourth group had one BESWL session targeted on the region of the common bile duct (CBD). Half of each group were sacrificed on the day of lithotripsy and half 1 week later. Post-mortem examinations were performed. Each implanted gallstone had fragmented. There were no findings attributable to BESWL in 11 animals. Three animals had pulmonary haemorrhagic spots (the largest was 10 mm in diameter) and one had a submucosal CBD petechia; these findings were attributable to BESWL. In two animals, microscopic haemorrhage associated with bronchopneumonia (usually present in our pig population) was more prominent than usual. This was possibly attributable to BESWL. The swine's deep posterior costophrenic sulcus makes it difficult to avoid the lung base during BESWL in swine. We conclude that this BESWL device can fragment gallstones without causing clinically significant soft-tissue damage.

Animals↗
PubMed1989

Aggressive osteoblastoma. A case previously reported as a recurrent osteoid osteoma.

We review the case of a 58-year-old man with a benign osteoblastic lesion. This originated in the base of the right second metacarpal and eventually involved several adjacent bones, persisting for at least 27 years despite 11 operations. It was originally reported in the literature as a recurrent osteoid osteoma, but we believe it is more properly diagnosed as an aggressive osteoblastoma, since the histological pattern did not change over the years. The lesion has remained locally aggressive with no evidence of malignant characteristics.

Adult↗
PubMed1988

Long-term occlusion of the porcine cystic duct by means of endoluminal radio-frequency electrocoagulation.

Recurrent cholelithiasis must be expected after gallstone removal without cholecystectomy. Chemical gallbladder ablation may offer prevention but requires preliminary cystic duct occlusion. Radio-frequency (RF) electrocoagulation of the cystic duct was performed in 15 pigs to induce occlusion by a controlled thermal epithelial injury. A flexible coagulation catheter was placed into the cystic duct lumen under fluoroscopic control by means of either subhepatic cholecystostomy or direct, percutaneous transhepatic gallbladder puncture. Complete cystic duct occlusion was proved in 14 animals. Follow-up ranged from 1 to 17 weeks (mean, 11 weeks). Histologically, the RF technique induced an intense chronic inflammatory and fibroblastic reaction, which eventually obliterated the coagulated cystic duct segments. There was no epithelial regeneration or recanalization of the fibrotic cystic duct segments. The adjacent structures, particularly the cystic artery, were intact in all specimens.

Animals↗
PubMed1988

Dedifferentiated chondrosarcoma of bone with leiomyosarcomatous mesenchymal component: a case report.

Dedifferentiated chondrosarcomas are well-described aggressive tumors arising from low-grade chondrosarcomas and containing high-grade mesenchymal sarcomatous components. These tumors are important to consider in the differential diagnosis of well-defined lytic lesions in the pelvis associated with large soft-tissue components. We present the plain film, computed tomographic, and angiographic findings of the first such reported tumor containing a leiomyosarcomatous component.

Bone Neoplasms↗
PubMed1986

Ruptured adenomyotic cyst of the uterus--a case report.

The clinical and pathological features of an apparently unique case of an adenomyotic cyst of the uterus are reported. The cyst was located within the subserosal myometrium of a 39-year-old woman. Prior to hysterectomy, it had ruptured with bleeding into the peritoneal cavity. The differential diagnosis of myometrial cysts is briefly discussed.

Adult↗
PubMed1986

Signet-ring cell lymphoma in the orbit: a case report and review.

The authors report on the first case of signet-ring cell lymphoma involving the orbit. This variant of non-Hodgkin's lymphoma contains either vacuolated or eosinophilic cytoplasmic inclusions that squeeze the nucleus to one side of the cell. In this case, the inclusions were eosinophilic and stained positively for PAS, immunoglobulin M (IgM) heavy chain and kappa light chain. Electron microscopy showed granular electron-dense material trapped within distended loops of rough endoplasmic reticulum. Twenty-two cases of signet-ring cell lymphoma previously reported elsewhere in the body are reviewed, and their clinical significance is discussed.

Cytoplasm↗
PubMed1984

Prostatic hyperplasia: radiological intervention. Work in progress.

Benign prostatic hypertrophy is the most common cause for urethral obstruction in males over 50 years of age. Interventional radiologic dilatation under fluoroscopic control offers a nonoperative alternative for treatment of prostatic hyperplasia. Cadaver studies with the use of arteriographic balloon catheters indicated that manual injection pressure provides effective dilatation of the prostatic urethra. Evaluation of symptom relief will have to await patient studies.

Cadaver↗
PubMed1983

Fine needle aspiration biopsy of the thyroid gland: a study of 304 cases.

We discuss the interpretation of thyroid aspiration cytology in the light of our experience and review the circumstances in which false positives and false negatives may occur. The technique is reliable but by no means infallible and it should not be regarded as a final diagnostic work-up. Its value lies in selecting patients with thyroid nodules for surgery. In the present series of 304 patients, 79 underwent operation and 37 malignancies were found. The incidence of malignancy among the surgically excised nodules was 47%, in contrast to 14% in the past. We estimated that 268 operations would be required to salvage the same number of malignancies without the use of fine needle aspiration biopsy.

Biopsy, Needle↗
PubMed1982

Widespread marrow necrosis during pregnancy.

Recently, a 22-year-old Caucasian female was referred to our Hospital two days post-partum. She had been feeling unwell during the last few days of her pregnancy and complained of multiple aches and pains, worst in the abdomen and lower back. Her admission platelet count was severely depressed and a bone biopsy showed extensive marrow necrosis with viable bony trabeculae. There was no evidence of vasculitis, vascular thrombosis, or malignancy. Widespread marrow necrosis in pregnancy followed by recovery, to our knowledge, has not been previously reported.

Adult↗