[Free-flap head and neck reconstruction failures: predictive factors and management]. / Les échecs de la chirurgie reconstructrice cervicofaciale par lambeaux libres : facteurs favorisants et prise en charge.

BACKGROUND: Failure after head and neck reconstruction using free flap are rare but their management remains a challenging problem. The purpose of this study was to analyze the causes and the subsequent treatment of free-flap failure in head and neck reconstruction. PATIENTS AND METHODS: A retrospective review of patients who had undergone free flap transfer between 2000 and 2007 was performed in our center. Data were collected from computerized medical record to determine patient and tumor characteristics, as well as their treatment. Moreover, a univariate analysis was performed to determine factors associated with free flap failure. RESULTS: Three hundred and twelve patients had a free flap transfer after head and neck cancer resection. A total of 22 failures (7%) were encountered. Previous surgery for head and neck cancer (p=0.02), surgery after cancer recurrence (p=0.02) and reconstructions after circular pharyngolaryngectomy (p=0.008) were significantly associated with free-flap failure. A second free-flap was performed in 12 patients and the overall success rate of the repeated free flap was 92 percent (11 of 12 patients). CONCLUSION: After a free flap failure, surgeons should determine subsequent treatments after a reconsideration of the need of a second free flap, an analysis of the cause of the first flap failure and an evaluation of local and general conditions. In selected patients, second free flap has a high success rate.

[Total pharyngolaryngectomy in the 21st century: indications, oncologic and functional outcomes]. / Les pharyngo-laryngectomies totales au 21ème siècle : indications, résultats carcinologiques et fonctionnels.

INTRODUCTION: The development of laryngeal preservation protocols has considerably modified the indications for total (pharyngo-)laryngectomy (TPL). The objectives of our study are to analyze the current indications for TPL and to evaluate the oncologic and functional outcomes after TPL and their predictive factors. METHODS: All patients who underwent TPL for squamous cell carcinoma of the larynx or hypopharynx, at our institution, between 2000 and 2009, were included in this retrospective study. Predictive factors of oncologic and functional outcomes were assessed in univariate and multivariate analyzes. RESULTS: A total of 130 patients were enrolled in our study including 119 men and 11 women, with a mean age of 65.9 years. TPL was realized for salvage in 65 patients. Extra-laryngeal tumor extension (n = 42) was the main indication for TPL in the 65 remaining patients. Overall survival was 49 and 41% at 3 and 5 years respectively. In multivariate analysis, primary tumor site (hypopharynx in comparison to larynx; p = 0.04) has a significant pejorative impact on overall survival. Oral alimentation (no enteral nutrition) was recovered successfully by 94% of the patients. In multivariate analysis, primary tumor site (hypopharynx) has a significant pejorative impact on functional results (deglutition: p < 0.0001; phonation: p = 0.03). CONCLUSION: Primary tumor site is one of the main predictive factor of oncologic and functional outcomes after TPL.

[Transoral and cervical approach without mandibulotomy for oropharynx cancer with fasciocutaneous radial forearm free flap reconstruction]. / Voie d'abord transorale et cervicale sans mandibulotomie dans les cancers de l'oropharynx avec réparation par lambeau libre fasciocutané antébrachial.

OBJECTIVE: To evaluate the role of a combined transoral and cervical approach without mandibulotomy for surgery of oropharyngeal cancer with fasciocutaneous radial forearm free flap reconstruction. MATERIAL AND METHODS: All patients who underwent this type of surgery between 2003 and 2007 were included in this retrospective study. We analyzed postoperative outcomes, surgical margins (histological study) and the oncological and functional results. RESULTS: A total of 24 patients were included in this study. There was no free flap failure. Surgical margins were negative for 23 of the 24 patients. At 3 years, overall, cause-specific, and disease-free survival rates were 73, 76 and 68%, respectively. A good functional result (normal or slightly impaired function) was obtained for oral diet, speech, mouth opening and esthetic outcome in 78, 82, 92 and 86% of the patients, respectively. CONCLUSION: This double surgical approach without mandibulotomy in selective cases can replace the transmandibular approach in locally advanced oropharyngeal cancer surgery.

[Papillary thyroid microcarcinomas: review of 230 cases]. / Les microcarcinomes papillaires de la glande tyroïde: à propos de 230 cas.

OBJECTIVES: Papillary microcarcinoma (PMC) is one of the most frequent pathological forms of thyroid cancer Here, we describe the circumstances of diagnosis and the clinical and pathological characteristics of this tumour We also analyze the therapeutic management and compare it with the recent published guidelines. METHODS: Between 2000 and 2006, a total of 230 patients with a PMC of the thyroid gland were included in this retrospective study. We have investigated the correlations between some pathological parameters (plurifocality, lymph node invasion...) and several factors (age, gender, tumour size...). RESULTS: The diagnosis of PMC was suspected in the preoperative period in 15% of the patients, and was confirmed intraoperatively by the pathologist in 42% of the cases. Plurifocal or bilateral PMC were discovered in respectively 30 and 17% of the patients. The rate of lymph node invasion in the central neck (level VI) was 26%. An elevated tumor size was correlated with a higher rate of plurifocal or bilateral PMC and of lymph node metastasis (p < 0.05). The indications for postoperative radioiodine therapy were reduced by approxiately 50% in the second part of our study. There were no case of thyroid PMC-related death. CONCLUSIONS: Even for these small tumours, tumour size remains correlated with the tumour aggressiveness. The place of radioiodine therapy in the management of thyroid PMC was progressively reduced because of the good prognosis of this tumour.

[Ameloblastomas]. / Les améloblastomes.

OBJECTIVES: The aim of this work was to report on the clinical, radiological and histological characteristics of ameloblastomas concerning bone structures of the face, rare but not exceptional tumours, and to communicate our experience of their treatment. MATERIAL AND METHODS: The authors reexamined six recent cases of patients presenting with ameloblastoma at the centre Antoine Lacassagne in Nice. The diagnostic context, the treatment and the development of the disease are given in detail, emphasizing the frequency of local relapse of this histologically benign condition. RESULTS: The study of these cases confirmed the benefit of surgical treatment of ameloblastoma. The frequency of local relapse in the cases of close resection, leaving in place micro-foci, justifies enlarged intervention, which is often bone destructive. CONCLUSION: When the continuity of the bone is interrupted, in particular at the level of the mandible, and if the general condition of the patient permits, repair is preferable. In this situation, the procedure of choice is micro-anastomosis of the fibula.

[Mandibular reconstruction with osseous free flaps: functional results]. / La reconstruction mandibulaire par lambeaux libres osseux: résultats fonctionnels.

OBJECTIVES: The aim of this retrospective study is to evaluate functional results of oromandibular reconstruction with osseous free flaps. MATERIAL AND METHODS: A total of 67 patients who underwent oromandibular reconstruction with fibula (n=60) or scapular (n=7) free flap between 2000 and 2004 were included in this study. We analysed functional results (alimentation, elocution, mouth opening and cosmetic appearance) and researched the potentially predictive factors of these results (age, comorbidity, preoperative irradiation, type of defect...; Chi(2) test). RESULTS: The rate of free flap success was 89.6%. A functional result considered as normal or subnormal was obtained by more than 50% of patients. Oral alimentation (without tube feeding) and intelligible speech were recovered by 92.5% of patients. Through and through defects and free flap failures were determinant predictive factors of worse functional outcomes. CONCLUSION: Fibula free flap is considered as the flap of choice for oromandibular reconstruction and allows excellent functional results.

[Head and neck reconstructive surgery with free flaps and quality of life: a prospective study]. / Chirurgie reconstructive cervico-faciale par lambeaux libres et qualité de vie: étude prospective sur 1 an.

OBJECTIVE: The aim of this prospective study is to evaluate functional results and quality of life after head and neck reconstructive surgery with free flaps. MATERIAL AND METHODS: All patients who have beneficed of head and neck reconstructive procedures with free flaps during the year 2004 were included in this study. EORTC quality of life questionnaire (QLQ-C30/H&N35) was used before and 6 months after surgery. A head and neck functional evaluation was realized 6 months after surgery. RESULTS: Thirty four patients were examinate 6 months after surgery. Global quality of life remained at its preoperative level (61.3% VS 62.8%). Physical, role and social functioning decreased significantly (p = 0.05), but emotional and cognitive functioning remained stable. Pain decreased considerably after treatment in the head and neck area (p = 0.001). Oral (eating: p = 0.05, speaking: p = 0.008) and sensorial functions (p = 0.001) decreased after treatment. All patients except one have recovered sufficient oral intakes, an intelligible speech and a good cosmetic result. CONCLUSION: Functional and cosmetic results after head and neck reconstructive surgery are the key factors of quality of life. Free flaps are considered actually as an indispensable technique to achieve an optimal reconstruction.

[Oropharyngeal reconstruction with radial forearm free flap: functional results]. / Les reconstructions buccopharyngées par lambeau libre antebrachial: résultats fonctionnels.

OBJECTIVE: The aim of this retrospective study is to evaluate functional results of oral and oropharyngeal reconstructions with radial forearm free flap. MATERIAL AND METHODS: We present our experience with radial forearm free flap for reconstructing oral and oropharyngeal defect between 2000 and 2004. A total of 96 patients were included in this study. We analysed functional results (alimentation, elocution, mouth opening and cosmetic appearance) and researched the potentialy predictive factors of these results (age, comorbidity, preoperative irradiation...; Chi 2 test). RESULTS: The rate of free flap success was 97.9%. Good functional results (normal or quasi normal function) were obtained for alimentation, elocution, mouth opening and cosmetic appearance in respectively 92.6%, 64.9%, 81.9% and 84.1% of cases. Age (p = 0.05), preoperative irradiation (p = 0.005) and T stage (p = 0,02) had a negative effect on elocution, free flap failure on mouth opening (p = 0.03), preoperative irradiation (p = 0.05) and free flap failure (p = 0,02) on cosmetic appearance. CONCLUSION: Radial forearm free flap is considered as the flap of choice for oral and oropharyngeal reconstructions and allows excellent functional results.

[Fibula free flap for reconstruction of extensive mandibular osteoradionecrosis]. / Lambeau libre de fibula pour la reconstruction des ostéoradionécroses mandibulaires évoluées.

OBJECTIVE: Treatment of mandibular osteoradionecrosis is always a therapeutic challenge. The aim of this article is to evaluate the interest of fibula free flap for mandible reconstruction after radical excision of osteoradionecrotic lesions. MATERIAL AND METHODS: Six consecutives cases of extensive osteoradionecrosis of the mandible were treated with fibula free flap reconstruction. We report a meticulous analysis of the cosmetic and functional results. RESULTS: All vascularized fibula osteocutaneous flaps transplanted were successful. Median hospital stay was 32 days. At 6 months, functional results (swallowing, mouth opening and speech) were good. All patients had sufficient oral intake and a comprehensible speech with just two patients requiring a soft diet and 1 patient retaining a moderate trismus. DISCUSSION: Extensive mandibular osteoradionecrosis requires a radical surgical treatment. Fibula free flap is the best solution for mandible reconstruction in this situation. This technique allows good functional results. CONCLUSION: Fibula free flap is the method of choice for mandible reconstruction after radical treatment of osteoradionecrosis.

Correlation between dihydropyrimidine dehydrogenase activity in peripheral mononuclear cells and systemic clearance of fluorouracil in cancer patients.

Dihydropyrimidine dehydrogenase (DPD) is the initial key enzyme in the catabolism of 5-fluorouracil (5-FU). We measured DPD activity in lymphocytes from 57 consecutive head and neck cancer patients while simultaneously monitoring 5-FU pharmacokinetics during 5-day, continuous infusion (1000 mg/m2/day) 5-FU therapy (82 cycles in total). The mean value for DPD activity was 0.186 +/- 0.068 (SD) nmol/min/mg of protein (range, 0.058 to 0.357). The mean value for 5-FU clearance was 2522.6 +/- 684.2 ml/min/m2 (range, 1052 to 4029). A significant linear correlation was observed between DPD activity and 5-FU clearance (r = 0.716, P less than 0.0001). DPD activity was poorly correlated to plasma uracil concentrations (r = -0.260, P = 0.0215). Likewise, plasma uracil concentrations were poorly correlated to 5-FU clearance (r = -0.214, P = 0.0595). In patients evaluated for more than one cycle (n = 18), there was large intrapatient variability in both DPD activity and 5-FU clearance. No significant difference was noted between cycles for DPD activity or 5-FU clearance (Kruskal-Wallis test). Monitoring DPD activity in lymphocytes may be useful in identifying patients at risk for altered 5-FU disposition.

Characterization of a new surface epitope specific for human epithelial cells defined by a monoclonal antibody and application to tumor diagnosis.

In an attempt to characterize the antigens attached to cells of a line established from a human squamous cell carcinoma of the tongue (CAL 27), BALB/c mice were immunized with whole CAL 27 cells; hybridomas were then produced using spleen cells of the animals and cells of an NS1 syngeneic myeloma. A hybridoma secreting a monoclonal antibody was obtained (CALAM 27); CALAM 27 was directed against an epitope attached to the CAL 27 cells. CALAM 27, IgG2a, reacted with a membrane antigen specific to all epithelial cells. After immunoprecipitation, this antigen corresponded to two bands (Mr 22,000 and 54,000). Reactivity disappeared when the tissue was embedded in paraffin but was conserved after fixation with acetone or methanol. This antigen was conserved for both benign and malignant epithelial cell pathologies. The action of CALAM 27 was tested on 80 samples of pleural effusions, ascites, and cerebrospinal fluid samples; after conventional cytological examinations, CALAM 27 failed to recognize either reactive mesothelial cells or meningothelial cells. In addition, the cell structure recognized by CALAM 27 is not found on certain lymphoid tissue cells. CALAM 27 also failed to react with small cell carcinoma of the lung. Its strictly epithelial specificity therefore permits its use for the diagnosis of micrometastases of carcinoma in ascites and cerebrospinal fluid, in pleural effusions, and in bone marrow. CALAM 27 may also prove useful in confirming diagnosis of pathologies suspected to be of epithelial origin.

Expression of epidermal growth factor receptor and survival in upper aerodigestive tract cancer.

PURPOSE: To determine the expression of epidermal growth factor receptor (EGFR) in head and neck squamous cell carcinoma and to evaluate its prognostic value. MATERIALS AND METHODS: EGFR was determined in tumor biopsies obtained from 109 consecutive patients with head and neck cancer (100 men, nine women). Control biopsies were obtained from 94 patients in a symetric nontumoral area of the same anatomic site. EGFR was measured by a binding assay using human recombinant iodine 125-EGF. RESULTS: The presence of detectable EGFR levels was found in all explored tumors with highly marked differences between patients (median, 71 fmol/mg protein; range, 2 to 2,302). In 93 of 94 cases, EGFR levels were higher in tumor samples as compared with healthy control zones. There was no significant difference in EGFR expression according to the various anatomic sites explored or tumoral differentiation status. There was a significant difference of distribution for EGFR levels between stages I and II tumors and stages III and IV tumors. The tumor EGFR levels were not linked to the response to first-line chemotherapy by cisplatin (CDDP) and fluorouracil (5FU). Survival was assessable for 103 patients for overall survival and for 81 patients for recurrence. EGFR overexpression was associated with shorter relapse-free (P = .0125) and overall survival (P = .028) rates. By multivariate analysis, the only significant variable was EGFR for relapse-free survival and tumor staging for overall survival. The association of EGFR to tumor staging markedly improves the significance for overall survival predictability (P = .002). CONCLUSION: EGFR determination deserves particular attention in head and neck cancer, since it independently carries a strong prognostic value.

Tumoral-reduced folates and clinical resistance to fluorouracil-based treatment in head and neck cancer patients.

PURPOSE: To describe the distribution of tumoral-reduced folates in cancer patients and to analyze the link between this parameter and antitumor efficacy of fluorouracil (FU)-based induction chemotherapy. PATIENTS AND METHODS: Ninety-five patients with head and neck squamous cell carcinoma were included in the present study and 41 received induction treatment with FU-based chemotherapy (35 men and six women; mean age, 59 years; range, 40 to 76). Thymidylate synthase (TS) activity was measured according to the tritium-release assay. Reduced folates (5-10 methylenetetrahydrofolate [CH2FH4] plus tetrahydrofolate) were measured according to the entrapment assay. RESULTS: Among the whole group of patients, reduced folates ranged from nondetectable (< 0.3) to 17.7 pmol/mg protein; CH2FH4 ranged from nondetectable (< 0.3) to 8.2 pmol/mg protein. There was no significant link between tumoral levels of reduced folates and the severity of disease stage. Among 41 treated patients, there were 12 (29%) complete responses (CRs), 18 (44%) partial responses (PRs), and 11 patients (27%) with no response (NR). No statistically significant relationship was observable between TS activity and response. The distribution of CH2FH4 in tumors was significantly higher for complete responders in comparison to patients with a PR or NR. CONCLUSION: The present clinical data demonstrate the importance of basal tumoral-reduced folates for the achievement of optimal efficacy of FU-based treatment. They may have implications for the identification of patients resistant to FU chemotherapy and for a better understanding and management of FU modulation by folinic acid (FA).

Relationship between fluorouracil systemic exposure and tumor response and patient survival.

PURPOSE: The aim of this study was to analyze the link between fluorouracil (FU) systemic exposure and tumor response and overall survival. PATIENTS AND METHODS: One hundred eighty-six patients (162 men, 24 women) with head and neck cancer were studied. All received cisplatin plus FU for three cycles as first-line chemotherapy. The treatment consisted of cisplatin (100 mg/m2 intravenously [IV]) followed by a 5-day continuous venous infusion of FU (1 g/m2/d). The median follow-up duration for the 104 patients alive was 24 months. For each cycle, we calculated the area under the curve over the duration of pharmacokinetic follow-up (AUC0-105 h) for plasma FU. For each patient, we analyzed the averaged AUC0-105 h and the averaged total dose for the three cycles. RESULTS: The response rate was 30% complete responses (CRs), 22% partial responses (PRs) more than 75%, 25% PRs less than 75%, and 23% no response (NR). Medians for averaged AUC and dose per cycle were 27,906 ng/mL h (first through third quartile, 25,398 to 31,060) and 7,000 mg (first through third quartile, 6,200 to 7,833), respectively. The tumor response was significantly linked to tumor stage (P < .001) and to averaged AUC (P = .05), but not to averaged dose. Analysis of parameters (continuous variable) expressing FU treatment intensity showed that dose did not influence survival contrary to the AUC (P = .001). The AUC remains significant (P = .025) in a multivariate analysis including tumor stage, demonstrating that the greater the FU systemic exposure, the longer the survival. CONCLUSION: These results strengthen the interest of individual FU dose adaptation based on pharmacokinetics.

Phase II trial of cisplatin, fluorouracil, and pure folinic acid for locally advanced head and neck cancer: a pharmacokinetic and clinical survey.

PURPOSE: To analyze clinical and pharmacokinetic data of cisplatin (CP)/fluorouracil (FU)/l folinic acid (l FA) chemotherapy administered as first-line treatment to locally advanced head and neck cancer patients. PATIENTS AND METHODS: Thirty-nine patients (35 men and four women; median age, 60 years; six stage III and 33 stage IV) received CP on day 1 (100 mg/m2) followed by l FA (200 mg/m2/d x 5) plus FU (500 mg/m2/d x 5) administered by continuous venous infusion (three cycles planned). Mean plasma concentrations of FU, l FA, and 5-methyltetrahydrofolate (5MTHF) over the cycle were computed. RESULTS: Clinical response was assessable for 33 patients. Response rates on the primary tumor site (n = 33) were 63.7% complete responses (CRs), 24.2% partial responses (PRs), and 12.1% treatment failures. Response rates on lymph nodes (n = 27) were 40.7% CRs, 37.1% PRs, and 22.2% treatment failures. The most frequent toxicity was mucositis (36.2% of cycles grade 3 to 4). Grade 3 to 4 nausea-vomiting, diarrhea, neutropenia, and thrombocytopenia occurred in 6.7%, 1.9%, 13.3%, and 1% of cycles, respectively. Pharmacokinetic analysis showed a wide interpatient variability for both FU (mean, 1.01 mumol/L; range, 0.16 to 2.09), l FA (mean, 1.89, mumol/L; range, 0.52 to 7.88) and 5MTHF plasma concentrations (mean, 3.85 mumol/L; range, 1.30 to 8.11). A significant correlation was demonstrated between FU concentration and hematologic toxicity grade, mucositis grade, and nausea-vomiting/diarrhea grade. Regarding tumor response, patients who failed to respond significantly exhibited lower FU and total folate concentrations than patients with a CR or PR. CONCLUSION: This study highlights the efficacy of CP/FU/l FA in head and neck carcinoma and establishes the clinical importance of coupled FU/FA pharmacokinetics to predict pharmacodynamic variability.

Response to fluorouracil therapy in cancer patients: the role of tumoral dihydropyrimidine dehydrogenase activity.

PURPOSE: The aim of the present study was to analyze the role of thymidylate synthase (TS; main cellular target of fluorouracil [FU]) and dihydropyrimidine dehydrogenase (DPD; rate-limiting enzyme of FU catabolism) in tumoral biopsies with respect to FU responsiveness. PATIENTS AND METHODS: This prospective study was conducted on 62 head and neck cancer patients (six stage II, 16 stage III, and 40 stage IV). All received first-line chemotherapy with biomodulated FU (5-day continuous infusion). Before treatment, a tumor biopsy and control biopsy (symmetrical nontumoral area) were obtained. Cytosolic TS and DPD activities were measured using radioenzymatic assays. RESULTS: DPD activity was detectable in all samples, without a significant difference between tumoral (median, 60 pmol/min/mg protein; range, 13 to 193) and nontumoral samples (median, 68 pmol/min/mg protein; range, 12 to 150). Tumoral TS and tumoral DPD were not significantly influenced by tumor localization or tumor staging. Among 52 tumors assessable for clinical response, we observed 46% complete responses (CRs), 33% partial responses (PRs), and 21% no responses (NRs). No relationship was demonstrated between TS activity and response to FU therapy. The comparison of tumoral DPD between complete responders and partial or nonresponders showed a trend toward significance (P = .06). In an attempt to reduce variability, we analyzed the tumoral/nontumoral DPD activity ratio; complete responders exhibited a significantly lower normalized DPD than partial or nonresponding patients (median, 0.86, 1.18, and 1.42 for CR, PR, and NR, respectively; CR v PR plus NR, P = .03). CONCLUSION: Although resistance to FU is multifactorial, the present clinical study suggests that FU catabolism in target cells is probably a determinant factor for FU responsiveness in cancer patients and justifies the clinical use of specific DPD inhibitors as FU biomodulators.

Influence of sex and age on fluorouracil clearance.

PURPOSE: Currently, fluorouracil (5-FU) is one of the major drugs used in cancer chemotherapy. Several investigators, including ourselves, have demonstrated a link between abnormalities in 5-FU clearance (Cl) and the risk of developing more or less 5-FU-related toxicities. Age and sex are among the host factors that have been implicated in the pharmacokinetic variability of drugs. Presently, no data are available on the possible influence of sex and age on 5-FU Cl. PATIENTS AND METHODS: Three hundred eighty patients (mean age, 61.7 years; range, 25 to 91; 301 men and 79 women) with squamous cell carcinoma (sre) of the head and neck were treated in our institution between 1987 and 1991. 5-FU Cl was determined for a total of 1,092 chemotherapy cycles. Each cycle consisted of cisplatin and 5-day continuous intravenous infusion 5-FU (daily doses ranging between 365 and 1,224 mg/m2). RESULTS: 5-FU Cl values (L/h/m2) showed a wide dispersion for both men (median, 179; range, 29 to 739) and women (median, 155; range, 56 to 466). 5-FU Cl values were lower significantly for women compared with men (P = .0005). When adjusted for age and dose, the influence of sex on log Cl remained significant (P = .013). There was no evidence that age modified 5-FU Cl when adjusted for sex and dose. Interestingly, for both men and women, the oldest patients (greater than 70 years) maintained their ability to clear 5-FU with daily doses that ranged from 500 to 1,000 mg/m2. CONCLUSIONS: These data indicate that the capacities to clear 5-FU are lower in women compared with men and are not influenced by age. It would be of interest to know whether this sex-related difference in 5-FU Cl may be clinically relevant by considering both toxicity and tumor response to 5-FU treatment.

Population study of dihydropyrimidine dehydrogenase in cancer patients.

PURPOSE: We conducted a prospective study on a large set of cancer patients in an attempt to evaluate the incidence of complete or partial dihydropyrimidine dehydrogenase (DPD) deficiency as found in peripheral mononuclear cells (PMNC). PATIENTS AND METHODS: One hundred eighty-five unselected consecutive cancer patients were included. The population consisted of 152 men (mean age, 62.1 years; range, 35 to 90) and 33 women (mean age, 59.2 years; range, 36 to 77). Sixty-eight were head and neck patients treated by a 5-day continuous infusion of fluorouracil (FU; starting dose, 1 g/m2/d, with dose adaptation based on pharmacokinetics) for which DPD activity was measured 2 to 3 days before FU administration (94 cycles analyzed). PMNC-DPD activity was measured by a radio-enzymatic assay using carbon-14-FU. RESULTS: DPD activity in the entire population showed a unimodal distribution, which globally fits a gaussian distribution. Mean and median DPD activity values were 0.222 and 0.211 nmol/min/mg protein, respectively (range, 0.065 to 0.559). No total DPD deficiency was found. Multifactor analysis of variance showed that liver function (biologic evaluation) and age did not influence DPD activity, but that DPD activity was, on average, 15% lower in women (0.194 nmol/min/mg protein) than in men (0.228 nmol/min/mg protein) (P = .03). No difference was demonstrated between premenopausal and postmenopausal women. In patients treated with FU, the risk of developing side effects was not linked to pretreatment DPD activity. FU-related toxicity was linked to FU systemic exposure. The correlation between pretreatment DPD activity and FU systemic clearance (CI) was weak (n = 90, linear regression r = .31, P = .002). Pretreatment DPD activity in patients who required a dose reduction was not significantly different from DPD activity in patients who did not require dose modification. CONCLUSION: From the present study, it appears that total DPD deficiency is a rare event. Although pretreatment DPD activity cannot be a useful indicator for improving FU dose adaptation strategy, the identification of severe DPD deficiency (< 0.100 nmol/min/mg protein) could lead to starting the treatment with a markedly reduced FU dose or even to using an alternative chemotherapy regimen.

Analysis of retinoic acid receptor beta expression in normal and malignant laryngeal mucosa by a sensitive and routine applicable reverse transcription-polymerase chain reaction enzyme-linked immunosorbent assay method.

Retinoic acid receptor beta (RAR-beta) seems to be a useful intermediate marker in trials of retinoids, and the aim of this work was to describe a fast, sensitive, and routine applicable method to measure RAR-beta expression in tumor biopsies. We developed a new technique combining reverse transcription-PCR with a colorimetric ELISA detection of amplification products. The principle of this nonradioactive method is based on digoxigenin labeling of PCR products during amplification. Amplified DNA is hybridized with a biotinylated capture probe. The generated hybrid is immobilized on a streptavidin-coated microtiter plate, and detection is performed with the use of an antidigoxigenin peroxidase conjugate. We applied this method to quantify the expression of RAR-beta and an internal control (beta2 microglobulin) in laryngeal tumors. We found a detection threshold at 50 pg of PCR products, which represents a 100-fold improvement when compared to the detection limit of ethidium bromide detection. The method was reproducible (intra- and interassay reproducibilities at 7 and 5%, respectively). We used this technique for determining RAR-beta expression in 20 patients with laryngeal carcinoma and in 20 patients without cancer. The data show that the value of the RAR-beta:beta2 microglobulin ratio is decreased in tumoral versus nontumoral specimens (P = 0.0012), which is consistent with previously published results.

Dihydropyrimidine dehydrogenase activity in cancer patients.

Dihydropyrimidine dehydrogenase (DPD) is the major catabolic enzyme of pyrimidines and fluoropyrimidines. The clinical course of 2 patients with suspected DPD deficiency is described. Both patients had significantly delayed clearance of fluorouracil (5-FU), elevated plasma uracil concentrations, and subsequent lethal toxicity. The prevalence of DPD deficiency in the general population is unknown, but given the large number of cancer patients treated with 5-FU, it may be of great clinical significance. Lymphocytes have been previously shown to be a useful marker of systemic DPD activity. Because DPD activity has not been previously reported in a large population of cancer patients using 5-FU as the substrate, we determined DPD activity in lymphocytes from 66 patients with cancer. DPD activity was determined by a sensitive high performance liquid chromatography method. The mean DPD activity (S.D.) in 66 patients with head and neck cancer was 0.189 (0.071) nomol/min/mg protein with wide interpatient variability (range 0.058-0.357). DPD activity was not correlated to age (r = -0.164, P = 0.188). The mean DPD activity in men [0.192 (0.074)] was not significantly different from that in women [0.172 (0.057); t-test P = 0.418]. Likewise, there was no statistical difference in DPD activity in patients who had not received prior chemotherapy [0.195 (0.066)] to patients receiving one or more cycles of chemotherapy [0.186 (0.074); t-test P = 0.638].