Philippe Monnier

Food groups and risk of oral and pharyngeal cancer

The role of specific food groups and diet variety on the risk of oral and pharyngeal cancer has been considered using data from a case‐control study conducted between 1992 and 1997 in the Swiss Canton of Vaud. Cases were 156 patients (126 males, 30 females) aged under 75 (median age 56) years with incident, histologically confirmed cancer of the oral cavity and pharynx, and controls were 284 subjects (246 males, 38 females, median age 57 years), admitted to the same university hospital for a wide spectrum of acute, non‐neoplastic conditions unrelated to tobacco and alcohol consumption or to long‐term modification of diet. After allowance for education, alcohol, tobacco and total energy intake, significant trends of increasing risk with more frequent intake emerged for eggs (OR = 2.3 for the highest tertile), red meat (OR = 2.1) and pork and processed meat (OR = 3.2). Inverse trends in risk were observed for milk (OR = 0.4 for the highest tertile), fish (OR = 0.5), raw vegetables (OR = 0.3), cooked vegetables (OR = 0.1), citrus fruit (OR = 0.4) and other fruits (OR = 0.2). The addition of a serving per day of fruit or vegetables was associated with an about 50% reduction in oral cancer risk. The most favourable diet for oral cancer risk is therefore given by infrequent consumption of red and processed meat and eggs and, most of all, frequent vegetable and fruit intake. Diet diversity was inversely related to oral and pharyngeal cancer: ORs were 0.35 for the highest tertile of total diversity, 0.24 for vegetable and 0.34 for fruit diversity. In terms of attributable risk, high meat intake accounted for 49% of oral and pharyngeal cancers in this population, low vegetable intake for 65% and low fruit intake for 54%. Int. J. Cancer 77:705–709, 1998.

Partial cricoid resection with primary tracheal anastomosis for subglottic stenosis in infants and children

Fifteen infants and children with a severe subglottic stenosis underwent a partial cricoid resection with primary tracheal anastomosis. The etiology of the stenosis was congenital in 3 cases and was acquired after prolonged intubation in 12. Fourteen patients were tracheotomy dependent at the time of surgery, and 13 (87%) of the 15 were classified grade III (7 cases) and IV (6 cases) according to Cotton. The resection included the cricoid only in 5 cases and the cricoid and a segment of trachea (1 to 4 rings) in 10 cases.

Supracricoid Partial Laryngectomy With Cricohyoidoepiglottopexy and Cricohyoidopexy for Glottic and Supraglottic Carcinomas

Objectives To review the patients operated in our department with supracricoid partial laryngectomy with either cricohyoidoepiglottopexy (CHEP) (59 cases) or cricohyoidopexy (CHP) (10 cases) technique, for primary or recurrent glottosupraglottic squamous cell carcinoma and compare the technique with other surgical or conservative approaches for treatment of laryngeal carcinoma.

Complications of different ventilation strategies in endoscopic laryngeal surgery: a 10-year review.

Background:Spontaneous ventilation, mechanical controlled ventilation, apneic intermittent ventilation, and jet ventilation are commonly used during interventional suspension microlaryngoscopy. The aim of this study was to investigate specific complications of each technique, with special emphasis on transtracheal and transglottal jet ventilation. Methods:The authors performed a retrospective single-institution analysis of a case series of 1,093 microlaryngoscopies performed in 661 patients between January 1994 and January 2004. Data were collected from two separate prospective databases. Feasibility and complications encountered with each technique of ventilation were analyzed as main outcome measures. Results:During 1,093 suspension microlaryngoscopies, ventilation was supplied by mechanical controlled ventilation via small endotracheal tubes (n = 200), intermittent apneic ventilation (n = 159), transtracheal jet ventilation (n = 265), or transglottal jet ventilation (n = 469). Twenty-nine minor and 4 major complications occurred. Seventy-five percent of the patients with major events had an American Society of Anesthesiologists physical status classification of III. Five laryngospasms were observed with apneic intermittent ventilation. All other 24 complications (including 7 barotrauma) occurred during jet ventilation. Transtracheal jet ventilation was associated with a significantly higher complication rate than transglottal jet ventilation (P < 0.0001; odds ratio, 4.3 [95% confidence interval, 1.9–10.0]). All severe complications were related to barotraumas resulting from airway outflow obstruction during jet ventilation, most often laryngospasms. Conclusions:The use of a transtracheal cannula was the major independent risk factor for complications during jet ventilation for interventional microlaryngoscopy. The anesthetist’s vigilance in clinically detecting and preventing outflow airway obstruction remains the best prevention of barotrauma during subglottic jet ventilation.

Partial cricotracheal resection for severe pediatric subglottic stenosis : Update of the Lausanne experience

Until recently, severe pediatric subglottic stenosis (SGS) has been treated almost exclusively by laryngotracheoplasty procedures. Even in the most experienced centers, the results of single-stage operations for Cottons grade III and IV stenoses have been disappointing. This paper reports our experience on 31 partial cricotracheal resections for severe SGS in infants and children. The stenosis was congenital in 6 cases and acquired after prolonged intubation in 25 cases. Twenty-seven patients were tracheotomy-dependent at the time of surgery. Twenty-two cases were classified as grade III and 9 cases as grade IV stenoses according to Cotton. The decannulation rate was 97% (30 of 31 cases) after an open procedure. There were no fatalities and no lesions to the recurrent laryngeal nerves, but there was 1 complete restenosis. Twenty-seven patients show no exertional dyspnea, 3 have a slight stridor with some dyspnea while exercising, and 1 patient is not decannulated. The voice is normal in 21 cases, a dysphonia is present in 9 cases, and the patient with complete restenosis acquired an esophageal voice. Postoperative follow-up is longer than 10 years in 8 cases and longer than 5 years in an additional 6 cases. All patients who reached adulthood show normal growth of the larynx and trachea. Considering the excellent results obtained in this consecutive series of 31 cases, partial cricoid resection with primary thyrotracheal anastomosis should be considered an important treatment option for severe SGS in infants and children.

Spectroscopic studies of photobleaching and photoproduct formation of meta(tetrahydroxyphenyl)chlorin (m-THPC) used in photodynamic therapy. The production of singlet oxygen by m-THPC

Meta(tetrahydroxyphenyl)chlorin (m-THPC) is a new photosensitizer currently undergoing clin. trials at Lausannes CHUV hospital for photodynamic therapy (PDT) of early cancer in the upper aerodigestive tract. The illumination of m-THPC with light at 650 nm in aq. soln. contg. 10% fetal calf serum (FCS) causes two simultaneously occurring processes: its photodegrdn. and the formation of a more stable photoproduct absorbing at 320 nm. The photodegrdn. quantum yield (FPb) of m-THPC is found to be of the order of 1.5*10-5 in 10% FCS. A strong dependence on oxygen concn. of the photodegrdn. and the formation of photoproducts has been obsd. Indeed, the m-THPC presents rather low FPb under N2-satd. conditions: 6.9*10-6. In aerobic conditions, the photodegrdn. as well as the formation of photoproducts, have been competitively inhibited by known singlet oxygen (1O2) quenchers. The addn. of superoxide dismutase (SOD), catalase or desferal, known quenching agents of type I mechanisms, has little or no effect on the rate of photobleaching and photoproduct formation of m-THPC. m-THPC generates 1O2 with a quantum yield of 0.3 in ethanol soln. as detd. by photo-oxidn. expts. using 1,3-diphenylisobenzofuran (DPBF) as substrate. The rate and quantum yield of DPBF photo-oxidn. are found to increase with increasing substrate concn. and decrease in phosphate buffer soln. (FD=0.01), due to the partially hydrophilic character of m-THPC. In addn., the reaction of 1O2 with TEMP (2,2,6,6-tetramethyl-4-piperidone) in combination with ESR (EPR) detection has been used to det. the formation of 1O2 by m-THPC in ethanol soln.

Clinical determination of tissue optical properties by endoscopic spatially resolved reflectometry

A noninvasive method to measure the optical properties of a diffusing and absorbing medium is described. Based on the spatially resolved measurement of diffuse reflectance at the sample surface, this method is particularly suitable for investigating the in vivo optical properties of biological tissues endoscopically in a clinical context. The sensitivity of the measurement is discussed, and two optical probes for two different clinical applications are presented. Preliminary measurements are performed on a nonbiological medium, which illustrate the possibilities of the proposed method. Finally, we report on in vivo measurements of the optical properties of the human esophageal wall at 630 nm.

The role of the CO2 laser in the management of laryngotracheal stenosis: a survey of 100 cases

Over the last decade, improvement of CO2 lasers with the microspot and ultrapulse technologies has broadened the indications for endoscopic CO2-laser resection of benign laryngotracheal stenosis (LTS). This article reviews 100 patients treated solely by endoscopic means for a LTS. There were 47 grade III, 41 grade II and 12 grade I stenoses according to the Myer-Cotton classification. The postoperative results show that the improvement to a nearly normal (>80% luminal size) airway declines from 92% (11/12 patients) for grade I to 46% (19/41 patients) for grade II and 13% (6/47 patients) for grade III stenoses. When compared to open surgery for more severe grades of stenosis (31 grade IV, 66 grade III and 3 grade II stenoses), the results of the endoscopy group is much less favorable: 36% of patients in the endoscopy group versus 76% of patients in the open surgery group were rehabilitated to a normal respiration without exertional dyspnea and 38% versus 5% patients remained tracheotomy dependent. However, if strict selection and therapeutic criteria are respected, a significant number of grade I and II stenoses, and to a lesser degree of grade III stenoses, can be improved to a nearly normal airway by endoscopic means only. The endoscopic treatment is potentially less invasive and risky and only needs a short hospital stay. To try this as a first treatment modality in a selected group of patients is worthwhile, provided that this endoscopic treatment is not repeated a second time, if the stenosis recurs to its initial grade after a primary CO2-laser treatment. Some guidelines for safe endoscopic treatment modalities with of the CO2 laser, dilatation and/or stenting are proposed.

Partial cricotracheal resection for pediatric subglottic stenosis: a single institution's experience in 60 cases.

Abstract. In our study, 60 infants and children, each with a severe subglottic stenosis (SGS), underwent partial cricotracheal resection (PCTR) with primary thyrotracheal anastomosis. According to the Myer-Cotton classification, two were grade II, 41 were grade III and 17 were grade IV stenoses. Of the 60 patients, 57 (95%) are presently decannulated, and one patient sustained a complete restenosis. Two patients with better than 80% subglottic airways still are waiting for decannulation: one because of bilateral cricoarytenoid joint fixation and the second because of temporary stenting of the subglottis with a Montgomery T-tube. The rate of decannulation is 97% (36 of 37 cases) in primary PCTRs, 100% (13 of 13 cases) in salvage PCTRs for failed laryngotracheal reconstructions (LTR) and 70% (7 of 10 cases) in extended PCTRs (i.e., PCTR associated with an additional open-airway procedure).

Long circulating half-life and high tumor selectivity of the photosensitizer meta-tetrahydroxyphenylchlorin conjugated to polyethylene glycol in nude mice grafted with a human colon carcinoma

In a model of nude mice bearing a human colon carcinoma xenograft, the biodistribution and tumor localization of meta‐tetrahydroxyphenylchlorin (m‐THPC) coupled to polyethylene glycol (PEG) were compared with those of the free form of this photosensitizer used in photodynamic therapy (PDT). At different times after i.v. injection of both forms of 125I‐labeled photosensitizer, m‐THPC‐PEG gave on average a 2‐fold higher tumor uptake than free m‐THPC. In addition, at early times after injection, m‐THPC‐PEG showed a 2‐fold longer blood circulating half‐life and a 4‐fold lower liver uptake than free m‐THPC. The tumor to normal tissue ratios of radioactivity concentrations were always higher for m‐THPC‐PEG than for free m‐THPC at any time point studied from 2 to 96 hr post‐injection. Significant coefficients of correlation between direct fluorescence measurements and radioactivity counting were obtained within each organ tested. Fluorescence microscopy studies showed that m‐THPC‐PEG was preferentially localized near the tumor vessels, whereas m‐THPC was more diffusely distributed inside the tumor tissue. To verify whether m‐THPC‐PEG conjugate remained phototoxic in vivo, PDT experiments were performed 72 hr after injection and showed that m‐THPC‐PEG was as potent as free m‐THPC in the induction of tumor regression provided that the irradiation dose for m‐THPC‐PEG conjugate was adapted to a well‐tolerated 2‐fold higher level. The overall results demonstrate first the possibility of improving the in vivo tumor localization of a hydrophobic dye used for PDT by coupling it to PEG and second that a photosensitizer conjugated to a macromolecule can remain phototoxic in vivo. Int. J. Cancer 76:842–850, 1998.© 1998 Wiley‐Liss, Inc.