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J L Pujol

Publications and source records attributed to J L Pujol.

At least 55 records · Page 3Linked to original sources
PubMed1996

r-metHuG-CSF support to ifosfamide, cisplatin, etoposide chemotherapy in non-small cell lung cancer.

Twenty patients with locally advanced or metastatic non-small cell lung cancer entered a study of recombinant human methionyl G-CSF (r-metHuG-CSF) as an adjunct to ifosfamide, cisplatin and etoposide (IPE) regimen. Chemotherapy consisted of three courses of cisplatin 25 mg/m2, ifosfamide 1.5 g/m2 (with uroprotection) and etoposide 100 mg/m2 given on days 1-4 of a 21-day cycle. r-metHuG-CSF, 5 micrograms/kg, was administered subcutaneously from day 5 to day 14. Eighteen out of 20 patients completed the three courses (57 evaluable cycles). Grade 3-4 neutropenia affected 50, 42 and 22% of the patients during cycles 1, 2 and 3, respectively, whereas thrombocytopenia was observed in 25% of the patients throughout the chemotherapy protocol. Haematological toxic events requiring transfusions and/or antibiotics were responsible for 11 unplanned hospitalizations. Among these only three were exclusively devoted to febrile neutropenia care, the remaining eight being mainly required for blood transfusions. There were no deaths during the study duration. Dose reductions were needed in 65% of the patients and chemotherapy was delayed by thrombocytopenia in five patients. The total relative dose intensity was 84%. Eleven (55%) patients responded (one complete and 10 partial responses). Median survival was 9.5 months. We concluded that IPE combination chemotherapy can be administered safely with the support of r-metHuG-CSF inasmuch as neutropenia appears as mild to moderate and manageable. Optimal delivery of chemotherapy is still limited by other toxicities, mainly thrombocytopenia, but the successful relative dose intensity observed herein deserves further studies designed to analyze a dose intensity-survival relationship in non-small cell lung cancer.

Aged↗
PubMed1996

Hypodiploidy, Ki-67 growth fraction and prognosis of surgically resected lung cancers.

One hundred and thirty-seven lung cancer patients (123 non-small-cell lung cancers (NSCLC), 10 small-cell lung cancers (SCLC) and four carcinoid tumours) who underwent surgery in an attempt at complete resection were prospectively entered in a study whose aim was to determine the prognostic significance of a hypodiploidy or a multiploidy pattern of tumour cell DNA content and a high immunohistochemical reactivity of Ki-67, a nuclear antigen related to the cell cycle. Indirect immunoperoxidase reactivity of Ki-67 on frozen tumour tissue sections was evaluated both visually, using a classical semiquantitative scale, and by means of a computer-assisted image processor. Cell DNA content analysis was done using static computer-assisted cytometry on tumour cytological prints stained by the pararosaline Feulgen-Schiff technique. The ploidy was characterised for each tumour by DNA index (DI), percentage of hypodiploid cells and type of DNA content histogram (near diploid, hyperdiploid, hypodiploid and multiploid). Ki-67 immunostaining was negative in 64 tumours (48%) and positive in 69 (52%). DNA histogram classification disclosed 57 (42%) near diploid tumours. Among the 80 (58%) aneuploid tumours, 16 were hypodiploid, 44 hyperdiploid and 20 multiploid. The prevalence of both a positive Ki-67 immunostaining and an aneuploid DNA histogram differed according to histology as SCLC demonstrated a higher frequency of both features when compared with NSCLC and carcinoid tumours. On the other hand, Ki-67 immunostaining and ploidy did not significantly differ according to degree of differentiation, nodal status and Mountain's stage grouping. The percentage of cells in the hypodiploid modal DNA was significantly higher for tumours which demonstrated a high Ki-67 immunostaining, suggesting a link between growth fraction and DNA content abnormalities. In univariate analysis, survival did not differ significantly according to either the Ki-67 immunohistochemical reactivity or the DNA index. Patients with a hypodiploid tumour had a shorter survival than patients with other DNA histogram patterns but, owing to the low frequency of hypodiploidy, this difference did not reach statistical significance. In Cox's proportional hazard model, an SCLC histology, an advanced tumour status, a positive nodal status and a hypodiploid tumour (hazard ratio: 2.070; 95% confidence interval 1.041-4.116) were significant determinants of survival. We conclude that hypodiploidy in lung cancer is a distinct DNA content abnormality as it contributes significantly to prognosis. Neither visually assessed nor computer-generated Ki-67 immunostaining measurements significantly determine prognosis.

Adult↗
PubMed1996

Lung cancer chemotherapy. Response-survival relationship depends on the method of chest tumor response evaluation.

In a previous study we found that tumor responses as assessed by CT scan and fiberoptic bronchoscopy are sometimes discordant. We hypothesize that the response-survival relationship might vary according to the method of tumor response assessment. In a multivariate analysis of survival using the landmark method, we evaluated the prognostic significance of tumor response assessed by CT scan or fiberoptic bronchoscopy together with bronchial tumor location and histology of bronchial biopsies at restaging. A total of 133 lung cancer patients (50 small cell lung cancers and 83 non-small cell lung cancers) were entered in controlled chemotherapy trials and prospectively evaluated for chest tumor response by CT scan and fiberoptic bronchoscopy (FOB). Only 106 patients were fully evaluable for response by both methods. For these patients, a statistical concordance was observed between the two tests (kappa = 0.271; p < 0.001). There was a significant correlation between response and survival whatever the test used. However, only CT scan evaluation resulted in a classification showing that the more unfavorable the response stage was, the worse the survival became with no intersection between survival curves. Cox's hazard model demonstrated that CT-evaluated progression, proximal bronchial location at second FOB (intermediate, main bronchus or trachea) and positive histologic status at restaging were all prognostic determinants of poor survival. In conclusion, CT-evaluated response led to the best response-survival relationship as this method classified patients into four groups with different outcomes. Fiberoptic bronchoscopy should be avoided in patients who were found to have no endobronchial lesion during the pretreatment staging. For patients with pretreatment assessable endobronchial lesions, the decision of a second FOB depends on the results of CT restaging: FOB is probably unnecessary in patients for whom progression is disclosed by CT scan. In patients for whom CT scan discloses tumor response or stabilization, bronchial tumor location and histology of bronchial biopsies at second FOB are independent prognostic factors.

Adenocarcinoma↗
PubMed1996

Cytokeratins as serum markers in lung cancer: a comparison of CYFRA 21-1 and TPS.

We examined two recently described cytokeratin markers, CYFRA 21-1 (cytokeratin fragment recognized by KS 19-1 and BM 19-21 antibodies) and TPS (specific M3 epitope of the tissue polypeptide antigen), in 405 lung cancer patients (91 small-cell and 314 non-small-cell lung cancers) and 59 patients presenting with nonmalignant pulmonary disease. Sensitivity-specificity relationship, as analyzed by receiver operating characteristic curves, demonstrated a higher accuracy of CYFRA 21-1 in comparison with TPS in both small-cell and non-small-cell lung cancers. Thresholds of 3.6 ng/ml and 140 U/L for CYFRA 21-1 and TPS respectively gave a 90% to 95% specificity. Sensitivity of CYFRA 21-1 was the highest in squamous-cell carcinomas (0.61) and the lowest in small-cell lung cancers (0.36), whereas sensitivity of TPS did not vary significantly according to histology (overall sensitivity, 0.40). In non-small-cell lung cancers, both serum CYFRA 21-1 and serum TPS distributions varied significantly according to Mountain's stage of the disease, nodal status, tumor status, and performance status, inasmuch as the worse each above-mentioned variable became, the higher the median and interquartile serum marker level was. Neither CYFRA 21-1 nor TPS was able to accurately discriminate between stage IIIa (marginally resectable) and stage IIIb (unresectable) non-small-cell lung cancers, however. In both small-cell and non-small-cell lung cancers, univariate survival analyses demonstrated that either a CYFRA 21-1 level over 3.6 ng/ml or a TPS level over 140 U/L significantly indicated a poor survival rate. In the whole population, taking into account other significant variables, Cox's model analysis demonstrated that a poor performance index, an advanced stage of the disease, the presence of metastases, elevated serum lactate dehydrogenase, and high serum CYFRA 21-1 (odds ratio, 1.74; 95% confidence interval, [1.33-2.27] were independent prognostic variables. We concluded that CYFRA 21-1 is a significant determinant of survival. Other applications of cytokeratin markers in lung cancer are still limited.

Adult↗
PubMed1996

Comparison of an expert system with other clinical scores for the evaluation of severity of asthma.

"Asthmaexpert" was produced at the special request of several clinicians in order to obtain a better understanding of the medical decisions taken by clinical experts in the management of asthmatic patients. In order to assess the severity of asthma, a new score called Artificial Intelligence score (AI score), produced by Asthmaexpert, was compared with three other scores (Aas, Hargreave and Brooks). One hundred patients were enrolled prospectively in the study during their first consultation in the out-patient clinic. Distribution of severity level according to the different scores was studied, and the reliability between AI and other scores was evaluated by Kappa and MacNemar tests. Correlations with functional parameters were performed. The AI score assessed higher levels of severity than the other scores (Kappa = 18, 28 and 10% for Aas, Hargreave and Brooks, respectively) with significant MacNemar test in all cases. There was a significant correlation between AI score and forced expiratory volume in one second (FEV1) (r = 0.73). These data indicate that the AI score is a severity score which defines higher levels of severity than the chosen scores. Correlations for functional parameters are good. This score appears easy to use for the first consultation of an asthmatic patient.

Adult↗
PubMed1996

[Results of a randomized study comparing combination of navelbine-cisplatin to combination of vindesine-cisplatin and to navelbine alone in 612 patients with inoperable non-small cell lung cancer].

The combination of vindesine and cisplatin is considered a reference regimen in advanced NSCLC which has yielded a significant improvement in the duration of survival. A phase II study of a new semi-synthetic vinca alkaloid, Navelbine, reported an unusually high 29% response rate in stage III-IV NSCLC and a phase I-II study established the feasibility of the combination of Navelbine and cisplatin. We, therefore, designed a prospective randomized trial to compare Navelbine and cisplatin (NVB-P) to vindesine and cisplatin (VDS-P) and to evaluate whether the best of these regimens affords a survival benefit compared to Navelbine alone (NVB), an outpatient regimen. Forty-five centers included 612 patients in this study: 206 in NVB-P, 200 in VDS-P and 206 in NVB. Navelbine was given at a dose of 30 mg/m2 weekly, cisplatin at 120 mg/m2 on day 1, day 29 and then every 6 weeks and vindesine at 3 mg/m2 weekly for 6 weeks and then every other week. Treatment was continued until progression or toxicity. Patients' characteristics were similar in the three groups with 59% of patients presenting with metastatic disease. An objective response rate was observed in 30% of patients in NVB-P versus 19% in VDS-P (P = .02) and 14% in NVB (P < .001). The median duration of survival was 40 weeks in NVB-P compared to 32 weeks in VDS-P and 31 weeks in NVB. The comparison of survival between the three groups demonstrated an advantage for NVB-P compared to VDS-P (P = .04) and NVB (P = .02). Neutropenia was significantly higher in the NVB-P group (P < .001) and neurotoxicity more frequent with VDS-P (P < .004). Since our results have demonstrated that NVB-P yields a longer survival duration and a higher response rate than VDS-P or NVB alone, with acceptable toxicity, this combination should be considered a reference regimen in advanced NSCLC.

Adult↗
PubMed1996

[Vectors of gene transfer. Applications in pneumology].

Human gene therapy in 1996 is a reality with almost 100 trials world-wide involving nearly 450 patients. The stakes are enormous. To assure the efficacy and safety of such a regime is mainly a problem of vector to carry the chosen nucleotide sequences. The ideal vector should have as a unique function that of the transport of the gene of therapeutic interest to the desired area at the proper quantity. The ideal vector does not currently exist and each system, viral or non-viral has both advantages and inconveniences.

Base Sequence↗
PubMed1996

[Bronchial cancer: from epidemiology to treatment].

The quest for an effective treatment for lung cancer is a major preoccupation for the medical community as it is now the leading cause of cancer mortality worldwide and its incidence continues to increase particularly in developing countries, in women and in patients under the age of 45 due to the high incidence of tobacco smoking. The major form of treatment for lung cancer is surgery whenever possible followed by chemotherapy either alone or in association with radiotherapy. The treatment of non-operable tumours can today be justified both by the slight but undeniable amelioration of survival rates and more importantly by an increase in the quality of life. Our experience, based on the treatment of 640 patients, suggests that the use of chemotherapy, which is legitimized by the high incidence of metastatic spread associated with the disease, leads to chemoresistant relapses in the case of small cell cancers and primary resistances in non-small cell cancer. Recent advances in the treatment of bronchial cancers are worth underlining as they have led to radical changes in daily practice. The efficacity of chemotherapy in the treatment of small cell cancers is based on a dose-effect relationship which justifies the use of induction therapy which, even if not particularly intensive, should be given at an optimal level. Moreover, thoracic radiotherapy is beneficial in the early stages of the disease. Chemotherapy increases the survival rates for patients with non small cell cancers and although this was difficult to demonstrate the effect is, today, widely accepted. Certain types of chemotherapy are oriented towards the optimisation of initial treatment with the aim of eradicating the microscopic metastatic disease (this is the case for chemotherapy intensification for small cell cancers and neo-adjuvant chemotherapy for non small cell cancers). Other strategies are aimed at maintaining a chemotherapy-induced tumoral response: possibly involving the use of interferons. Whilst thoracic oncology cannot promise exciting breakthroughs in the short-term, present phase III trials with new cytostatic drugs and new therapies give rise to real hopes for the future.

Bronchial Neoplasms↗
PubMed1995

Phase I study of percutaneous 4-hydroxy-tamoxifen with analyses of 4-hydroxy-tamoxifen concentrations in breast cancer and normal breast tissue.

4-OH-tamoxifen is an active metabolite of tamoxifen that is detectable in the serum and tumour tissue of patients treated by oral tamoxifen. As this metabolite penetrates through the skin, it is possible to compare percutaneous 4-OH-tamoxifen (4-OH-TAM) and oral tamoxifen treatments. We report herein a randomized study of percutaneous 4-OH-TAM versus oral tamoxifen in women with breast cancer. This pharmacology study was designed to compare the 4-OH-TAM concentration in breast cancer and normal breast tissue according to the route and dose used for administration of tamoxifen after a 3-week period prior to surgery and tissue sampling. Women were randomized into one of the five following groups: group I, oral tamoxifen given at 10 mg twice a day; group II, 4-OH-TAM delivered percutaneously at 0.5 mg day to both breast areas; group III, 4-OH-TAM applied percutaneously at 1 mg/day to both breast areas; group IV, 4-OH-TAM delivered percutaneously at 1 mg/day to a large cutaneous area excluding the breasts; and group V, 4-OH-TAM applied percutaneously at 2 mg/day to a large skin area excluding the breasts. 4-OH-TAM plasma and tissue concentrations were significantly higher in the oral tamoxifen group as compared with either the high- or the low-dose percutaneous 4-OH-TAM group. In group II, percutaneous 4-OH-TAM treatment resulted in tissue concentrations of 1,446 and 352 pg/g in tumour tissue and normal breast tissue, respectively. In group I these concentrations were as follows: tumour tissue, 12, 453 pg/g; and normal tissue, 10,214 pg/g. 4-OH-TAM concentrations in tumour tissue and normal breast tissue did not significantly differ in any group. In the oral group we observed classic effects on coagulation and lipid metabolism when pre- and post-treatment values of these biological variables were compared, whereas no difference was observed in the percutaneous group. Although percutaneous administration of 4-OH-TAM led to a low plasmatic concentration of this active metabolite, the breast tissue concentration remained lower than those observed after oral tamoxifen treatment. Therefore, at the doses described in this study, percutaneous 4-OH-TAM cannot be proposed as an alternative tamoxifen treatment.

Administration, Cutaneous↗
PubMed1995

Carcinoid tumors of the lung: do atypical features require aggressive management?

Atypical carcinoids are an intermediate form of tumor between low-grade malignant typical carcinoid and high-grade malignant small cell carcinoma, which represent the two ends of the spectrum of neuroendocrine bronchopulmonary tumors. Between 1983 and 1993, 27 patients with atypical carcinoids underwent surgical treatment. The histologic diagnosis of an atypical carcinoid was established if the criteria proposed by Arrigoni and associates were fulfilled. Seven pneumonectomies, 16 lobectomies, 2 segmentectomies, and 2 wedge resections were performed. Thirteen patients (48.1%) had regional nodal metastases and 6 patients (22%) had N2 disease at the time of surgical therapy. Distant metastases developed in 5 patients (18.5%) after initial treatment. The 10-year survival in patients with an atypical carcinoid was 49%, versus the 84% 10-year survival rate observed in patients with a typical carcinoid. We conclude that the aggressive behavior of atypical carcinoids precludes the use of limited surgical resection and requires a more aggressive approach, with lobectomy and mediastinal lymph node dissection constituting a minimal procedure. The same criteria used for well-differentiated lung carcinoma should apply to this form of neuroendocrine lung tumor. Adjuvant chemotherapy is recommended for patients with stage III or distant metastases.

Adult↗
PubMed1995

Typical and atypical bronchopulmonary carcinoid tumors: a clinicopathologic and KI-67-labeling study.

Expression of a proliferating antigen by KI-67 immunohistochemistry was analyzed with a SAMBA 2005 computer-assisted image processor (Traitement de l'Information for des Techniques Nouvelles, Grenoble, France) in 47 surgically resected bronchopulmonary carcinoids embedded in paraffin. The clinicopathologic characteristics and KI-67 labeling, expressed in percentage of stained nuclear surface relative to the total nuclear surface, of 31 typical carcinoids and 16 atypical carcinoids were compared and assessed with respect to patient survival. The proliferation status was significantly higher in histologically atypical than in typical carcinoids. Moreover, using a 4% cutoff, we observed a significant difference for the 4-year overall survival rate. Semiquantitative analysis of the proliferation index by KI-67 immunostaining seemed to be an effective means of identifying high risk subsets among patients with histologically atypical carcinoids and for whom adjuvant chemotherapy could be proposed.

Biomarkers, Tumor↗
PubMed1995

Neoadjuvant chemotherapy of locally advanced non-small cell lung cancer.

Neoadjuvant chemotherapy was tested in non-small cell lung cancer in an attempt to increase the resectability of the tumor and to treat the microscopic metastatic disease known to be responsible for the majority of failures in surgically treated patients. This review deals with published trials. Most of them are feasibility studies in Stage III NSCLC. Obviously, the heterogeneity of eligibility criteria from one study to another prevents general conclusions on the usefulness of neoadjuvant chemotherapy. However, it is possible to conclude that neoadjuvant chemotherapy has an antitumor activity; the majority of the studies report a 60% objective response rate including a significant number of complete responses and a 50% complete resection rate. Neoadjuvant chemotherapy does not increase morbidity after surgery except when it is combined with preoperative radiation therapy. At the time of writing, one Phase III randomized study comparing neoadjuvant chemotherapy followed by surgery with surgery alone has been published. This study concludes that the combined modality treatment improves the survival of patients with locally advanced non-small cell lung cancer. Taken as a whole, the literature deserves further studies to determine the place of neoadjuvant chemotherapy in lung cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1995

Interleukin-1 alpha and soluble interleukin-2 receptor during small cell lung cancer chemotherapy: comparison of high chemotherapy dose with rhGM-CSF and standard chemotherapy dose without rhGM-CSF.

This study was designed to analyze the possible immunomodulation induced in vivo by haematopoietic growth factors following anti-cancer chemotherapy. Haematologic and cytokine kinetics (IL-1, IL-6, TNF alpha and soluble interleukin-2 receptor (sIL-2R)) were studied in patients with SCLC receiving high dose regimens of chemotherapy and recombinant human GM-CSF (group A), or standard doses of chemotherapy without rhGM-CSF (group B). Six patients were prospectively enrolled and randomized in each group. The kinetics of haematopoiesis following chemotherapy did not significantly differ between the two groups. In group A, the plasma sIL-2R level increased regularly during rhGM-CSF treatment reaching a 2.5-fold elevation at day 12 whereas it remained stable in group B. Conversely, IL-1 alpha decreased to an undetectable level in group A whereas it increased slightly from day 14 to day 18 in group B. As sIL-2R could compete with lymphocyte surface receptors and as IL-I is an important cytokine involved in acute phase response, our results might be regarded as reflecting a transient decrease in the cell-mediated immune response in small cell lung cancer patients receiving high dose chemotherapy combined with rhGM-CSF.

Adult↗
PubMed1995

[Evaluation of tumor response during chemotherapy of bronchial cancer].

Chemotherapy of lung cancer is still an experimental approach requiring careful evaluation. Tumour response (marker of anticancer activity) is not perfectly correlated to survival (marker of chemotherapy efficacy), but its evaluation remains a milestone inasmuch as reporting a wrong tumour response rate might lead to the rejection of active new treatments. This review deals with the method of tumour response measurements and its use during a chemotherapy protocol. Recommendations drawn from the analysis of the literature are: 1) to assess and classify all lesions which can be identified at the beginning of the treatment; 2) to define the target lesions, mainly the ones which can be bidimensionally measured; 3) to use the World Health Organization recommendations for reporting the overall response; 4) to confirm complete response by negative rebiopsies; 5) to avoid second fiberoptic bronchoscopy to patients with stable or progressive disease on CT-scan, and finally; 6) to assess response quality by evaluating response duration and improvement of quality of life.

Antineoplastic Agents↗
PubMed1995

Fos immunoreactivity assessment on human normal and pathological bronchial biopsies.

The transcription factor Fos is involved in cell proliferation and differentiation. Its expression in normal and pathological adult human tissues and cells has rarely been studied. We therefore studied bronchial biopsies obtained from 14 normal subjects (NS), 18 non-steroid-treated asthmatics, 10 corticosteroid-treated asthmatics and 10 patients with chronic bronchitis (CB), in addition to 34 patients with lung cancer (LC), by immunofluorescence for Fos immunoreactivity, using a highly specific polyclonal antibody. Bronchial tissue of 0/10 NS, 11/18 non-steroid-treated asthmatics, 1/10 steroid-treated asthmatics, 0/10 CB and 1/34 LC expressed Fos. In asthmatic patients, the expression was heterogeneous, localized to epithelial cells and correlated with the epithelium shedding (tau = 0.45, P = 0.0001). Corticosteroid-treated patients rarely expressed Fos, suggesting a role for this proto-oncogene in asthmatic bronchial inflammation. Fos was rarely expressed in the normal and pathological (CB, LC) proliferative compartment of the human bronchi, suggesting its low role in cell proliferation of the large airways.

Adenocarcinoma↗
PubMed1995

[CYFRA 21-1 and bronchial cancer].

CYFRA is a new marker which measures a fragment of cytokeratin 19 in the serum by an immune radiometric method. The test is based on the preservation of the cytokeratin expression on the epithelial cells during the course of malignant transformation. In immuno-histochemistry the antibodies which selectively recognise cytokeratin react with all histological types of bronchial cancer. The presence of cytokeratin in the serum of patients suffering from cancer would be linked to their liberation during the course of cellular death. The threshold of specificity for CYFRA 21-1 is 3.3.3.6 ng/ml in a population suffering from benign respiratory diseases. The study performed in bronchial cancer produced the following conclusions: the marker is, above all, useful for epidermoid cancer; it is more discriminating than other markers to separate bronchial cancers and non-malignant respiratory disease. An elevated level of CYFRA 21-1 is predictive of advanced disease but does not permit any prediction as to inoperability. In 65% of cases, variations of CYFRA 21-1 are concordant with the stage of the disease during chemotherapy. Finally, elevated levels of CYFRA 21-1 predict a poor prognosis independent of the state of the disease.

Biomarkers, Tumor↗
PubMed1994

[Oncogenes and anti-oncogenes in lung cancer].

In all normal cells, two type of genes, oncogenes and anti-oncogenes, are expressed and control cell proliferation and differentiation. Cell growth is stimulated by oncogenes and inhibited by anti-oncogenes. Cancerization involves loss of control due to defective gene expression either by overexpression of a normal protein (loss of quantitative control) or expression of an abnormal protein (loss of qualitative control). Several oncogenes have been identified. They include three oncogenes, c-myc, N-myc and L-myc, known to be overexpressed in small-cell carcinomas of the lung. Point mutations of the oncogene K-ras is found in 15 to 30% of adenoma carcinomas, especially in smokers. Loss of anti-oncogene function has also been described in processes leading to lung cancer. Chromosome abnormalities, for example the 3p14-23 deletion described in 1982, are found in 100% of small-cell carcinomas and in 50% of non-small-cell carcinomas. This deletion is never found in normal tissue. The gene involved has not yet been cloned. Other mutations or deletions include the RB gene, necessary for neuroendocrine differentiation, and the p53 gene which has undergone mutation in 50% of the non-small-cell carcinomas and 70% of the small-cell carcinomas. These acquired mutations are strongly associated with tobacco smoking. Oncogenes and anti-oncogenes play an important role in the complex step-wise process leading to cancerization. As tumour characterization becomes more precise and precancerous states better controlled, future treatments may relief on inhibiting tumoural growth by using drugs which would substitute for the lost effect of anti-oncogenes or inhibit activation of an oncogene. But at the present time, it is still difficult to define criteria predicting high risk of postoperative relapse or resistance and further studies investigating the correlation between genetic abnormalities and clinical staging and survival curves are required.

Cell Transformation, Neoplastic↗