Biomedical subjects

L P Kowalski

Publications and source records attributed to L P Kowalski.

At least 19 recordsLinked to original sources

PubMed2006

Reconstruction of large defects postmandibulectomy for oral cancer using plates and myocutaneous flaps: a long-term follow-up.

A series of 28 consecutive cases of mandibular reconstruction by means of reconstructive plates and myocutaneous flaps were reviewed. In all cases mandibular resection was indicated for treatment of squamous cell carcinoma of the oral cavity: 25 pelviglossomandibulectomies (resulting in large defects from the angle of the mandible), 2 Commando operations (resulting in lateral defects) and 1 anterior sectional mandibulectomy (resulting in an anterior defect). Tumour stages were T1-T2 (4 cases) and T3-T4 (24 cases). Success was defined as plate maintenance 6 months' postoperatively/postradiotherapy. The overall success rate was 32.2%. Lateral-centre-lateral (L-C-L) defects had 32% success, L (lateral) defects had 50% success and in the single case of a C (centre) defect, the plate was not maintained. Stainless steel reconstruction plates showed a similar success rate as titanium plates (30% versus 34%). In cases not submitted to radiotherapy there were more maintained plates than in cases that received radiotherapy (45.5% versus 23.6%). Reconstruction plates are not effective in bridging large defects of the resected mandible. Only in selected cases that are not eligible for microvascular free flaps should plates and myocutaneous flaps be considered as an option for mandibular reconstruction.

Adolescent↗

PubMed2005

Primary intraosseous fibrosarcoma of jaw.

This paper reports one case of primary fibrosarcoma affecting the mandible in a 41-year-old woman. Microscopically, the tumor was cellularized with an intense mitotic activity, and areas of necrosis and hemorrhage, and the cells showed immunoreactivity only for vimentin, establishing the diagnosis of primary intraosseous fibrosarcoma. The patient underwent tumor surgical resection, supraomohyoid neck dissection and mandible reconstruction with fibula flap and titanium bar. She also received post-surgical radiotherapy and is in follow up for 36 months without signs of recurrence or metastases.

Adult↗

PubMed2004

PCNA, Ki-67 and p53 expressions in submandibular salivary gland tumours.

Salivary gland tumours are uncommon with a broad heterogeneity. The most common benign tumour is the pleomorphic adenoma, whereas mucoepidermoid carcinoma and adenoid cystic carcinoma predominate among the malignancies. Most salivary gland tumours occur in the parotid, and consequently clinical and biological data are normally derived from this site. This work describes the expressions of PCNA, Ki-67 and p53 in 15 pleomorphic adenomas, 15 mucoepidermoid carcinomas and 15 adenoid cystic carcinomas of the submandibular gland. Our results showed that all pleomorphic adenomas were negative for p53 and Ki-67 with 66.6% being positive for PCNA. Conversely, p53 was positive in 53% of the mucoepidermoid carcinomas and in 20% of the adenoid cystic carcinomas. Ki-67 was expressed in 47.7% of the mucoepidermoid carcinomas and 40% of the adenoid cystic carcinomas. All malignant tumours were positive for PCNA. These results indicate that the proliferative rate analysed with PCNA and Ki-67 and the expression of p53 in pleomorphic adenoma and adenoid cystic carcinoma of the submandibular gland were similar to those described in the parotid and minor salivary glands. However, mucoepidermoid carcinomas showed higher expression of these markers than those of other salivary glands. This work is the first describing the expression of these immunohistochemical markers exclusively in submandibular salivary gland tumours.

Adenoma, Pleomorphic↗

PubMed2004

The CAG repeat polymorphism in the androgen receptor gene (AR) and its relationship to head and neck cancer.

Sex hormones may play an important role in the tumorigenic process of the head and neck. The aim of our work was to investigate whether the androgen receptor (AR) CAG repeat polymorphism is associated with an increased relative risk for head and neck cancer. Genomic DNA from 103 male patients with head and neck carcinomas and 100 male controls were analyzed for the AR CAG polymorphism by PCR amplification and direct sequencing or denaturing polyacrilamide gel electrophoresis. Logistic regression analysis showed a significant association between CAG repeat length and risk of head and neck cancer in individuals with more than 20 CAG repeats [OR=2.54 (95% CI, 1.3-4.8)]. For the group of individuals with oral and laryngeal cancer the estimated relative risk was increased to 2.79 (95% CI, 1.2-6.3) and 3.06 (95% CI, 1.0-9.6), respectively, in men with CAG repeat length >20. These results suggest, for the first time, that shorter AR CAG repeat alleles have a protective effect for head and neck cancer development.

Adult↗

PubMed2003

Oral metastasis of telangiectatic osteosarcoma.

Metastases of osteosarcoma in the mouth are rare, and only few cases have been described. We present a case of telangiectatic osteosarcoma of the femur in a 15-year-old girl, who developed metastases in the humerus, lungs and retromolar area 4 years after initial diagnosis and treatment. The girl died 2 months after the diagnosis of metastases despite treatment with chemotherapy. This report emphasizes that telangiectatic osteosarcoma has a very poor prognosis, particularly when multiple metastases develop.

Adolescent↗

PubMed2003

Eotaxin expression in oral squamous cell carcinomas with and without tumour associated tissue eosinophilia.

AIM: Eotaxin is a powerful and selective eosinophil chemoattractant. The purpose of this study was to compare the expression of eotaxin in oral squamous cell carcinomas with and without tumour associated tissue eosinophilia (TATE). The mechanisms that control the recruitment of eosinophils to these tumours are not clearly established. METHODS: A total of 60 patients with oral squamous cell carcinomas (OSCC) with TNM stages II and III, located in the tongue, oral floor, retromolar area and inferior gingiva were divided in two groups: 1--OSCC with intense eosinophilic inflammatory infiltrate and 2--OSCC with absent/low eosinophilic inflammatory infiltrate. The eotaxin expression was analyzed by immunohistochemistry using standard streptavidin-biotin-peroxidase complex technique with monoclonal (mouse anti-human eotaxin) and polyclonal (rabbit anti-human eotaxin) antibodies. RESULTS: The eotaxin expression was identified in normal oral mucosa as well as in both OSCC groups including malignant epithelial cells, eosinophils, neutrophils, plasma cells and fibroblasts. The eosinophils showed intense immunopositivity for eotaxin. CONCLUSION: These results suggest that the eotaxin expressed in oral squamous cell carcinomas, mainly derived from eosinophils, is probably involved in the mechanisms of eosinophils chemotaxis to the tumour and in the maintenance of TATE in these malignant tumours.

Adult↗

PubMed2003

Sites of recurrence in oral and oropharyngeal cancers according to the treatment approach.

OBJECTIVE: The purpose of this study is to evaluate the rates and the sites of tumour recurrence in patients with oral and oropharyngeal carcinomas. DESIGN: This is a retrospective study of a series of cases treated in a single institution. PATIENTS AND METHODS: A series of 2067 patients with oral and oropharyngeal squamous carcinoma, treated from 1954 to 1998 were analysed. The treatment approach was: surgery, 624 cases (30.2%); radiotherapy alone, 729 cases (35.3%); radiotherapy and surgery, 552 cases (26.7%) and radiotherapy and chemotherapy, 162 cases (7.8%). MAIN OUTCOME MEASURES: Tumour recurrence was observed in 1079 patients (52.2%): 561 cases of local recurrences (27.1%); 168 neck recurrences (8.1%); 252 locoregional recurrences (12.2%); 59, distant metastasis (2.9%) and 39 (1.9%), combination of distant metastasis with local, neck or locoregional recurrence. RESULTS: The rates of recurrence varied significantly according to the treatment performed. Oral cavity cancer patients undergoing radiotherapy alone or in combination with chemotherapy presented the highest rates of neck recurrences (22.5 and 40.0%, respectively) for clinical stage (CS) I/II and of local (41.2 and 30.1%) and locoregional (21.7 and 31.1%) recurrences for CS III/IV; yet, for CS III/IV, surgery without neck dissection was associated with the highest rates of neck recurrences (20.7%), but no differences were observed in the rates of local or locoregional recurrences for CS I/II patients. For oropharynx cancer patients with CS I/II there was no difference in the rate of locoregional failures according to the treatment. However, patients with CS III/IV undergoing radiotherapy present a highest rate of local (42.3%) and locoregional (28.8%) failures. CONCLUSION: The results suggest that surgery should be the first option for initial clinical stage oral and oropharyngeal cancers. For advanced cases independently of the site of the tumour, surgery and postoperative radiotherapy should be the standard of care because it is associated with the lowest rates of locoregional recurrence.

Adolescent↗

PubMed2003

Central mucoepidermoid carcinoma of the mandible: report of four cases with long-term follow-up.

Central mucoepidermoid carcinomas are uncommon tumours, representing about 2 to 4% of all mucoepidermoid carcinomas. They are histologically low-grade cancers, usually affecting the mandible as uni- or multilocular radiographic lesions. The authors report four cases of central mucoepidermoid carcinomas affecting the mandible and discuss their clinical, radiographic and histological findings. Four females were affected, with a mean age of 42 years and all cases involved the posterior mandible. Treatment included surgery in three cases and surgery associated to neck dissection and radiotherapy in one case. Two patients showed no recurrence and were alive without signs of the disease after a mean follow-up of 78 months. The other two patients showed local recurrence and one was alive with disease after a follow-up of 384 months, and the other was followed-up for 324 months dying by other causes without signs of the tumour. Central mucoepidermoid carcinomas of the mandible are low-grade tumours, and effective surgical treatment involving wide local excision or en bloc resection allows patients to have a favourable prognosis after long-term follow-up.

Adult↗

PubMed2003

Salivary duct carcinoma: immunohistochemical profile of an aggressive salivary gland tumour.

BACKGROUND: Salivary duct carcinoma (SDC) is considered to be a distinct malignancy of the major salivary glands, because of its highly aggressive behaviour, and the high rate of recurrence, metastasis, and disease related death. AIMS: To investigate expression of the proteins involved in the retinoblastoma (pRb) and p53 pathways, which control cell cycle progression at the G1/S checkpoint, and also expression of the c-erbB-2 oncoprotein in SDCs. METHODS: Using a streptavidin-biotin method, five cases of SDC were evaluated immunohistochemically for the presence of cyclin D1, CDK4 (cyclin dependent kinase 4), p16 (CDK2A), pRb (retinoblastoma protein), E2F-1, p53, mdm2 (murine double minute 2), bcl-2, and the c-erbB-2 oncoprotein to determine whether there was a correlation between the expression of these proteins and patient outcome. RESULTS: All of the cases showed deregulation of the pRb and p53 pathways. Of the five patients analysed, only the patient with longterm survival (10 years) was not positive for c-erbB-2 expression. CONCLUSIONS: c-erbB-2 overexpression was associated with a poor prognosis. Aggressive behaviour, recurrence, and metastatic potential do not appear to be related to cell cycle deregulation, but seem to be associated with the c-erbB-2 oncoprotein, which is involved in matrix degradation and proteolitic activity, in addition to increases in vessel permeability, endothelial cell growth, proliferation, migration, and differentiation. There was a correlation between c-erbB-2 oncoprotein expression and aggressive behaviour in SDCs.

Aged↗

PubMed2002

Immunohistochemical distinction of high-grade mucoepidermoid carcinoma and epidermoid carcinoma of the parotid region.

The correct diagnosis of high-grade mucoepidermoid (MEC), which is composed of solid islands of intermediate and squamous cells, may be challenging, due to its similarity to other tumours, mainly with squamous cell carcinoma (SCC). The present report employed immunohistochemical technique against different cytokeratins (CKs), in order to differentiate these two entities. : Six high-grade MEC and six SCC of the parotid region, retrieved from the files of both Oral Pathology Department of the School of Dentistry of University of São Paulo and Pathology Department of A.C. Camargo Hospital, were submitted immunohistochemical technique against Cks 7,8, 10, 13, 14 and 19. : High-grade MEC was positive for Cks 7, 8, 13, 14 and 19. The cases of SCC showed strong positivity for CK14, and CK10 was present only in focal areas. Our results highlight the use of CKs (especially CK14) to differentiate high-grade MEC and SCC.

Adult↗

PubMed2002

Tumour-associated tissue eosinophilia as a prognostic factor in oral squamous cell carcinomas.

AIMS: Tumour-associated tissue eosinophilia has been described in many sites, including head and neck. The mechanism of eosinophil recruitment and its role in tumours has not yet been defined, and its presence has been related to a favourable as well as unfavourable prognosis. The aim of this study was to evaluate the influence of tumour-associated tissue eosinophilia on the prognosis of 125 oral squamous cell carcinoma patients. METHODS AND RESULTS: The number of eosinophils was obtained by morphometric analysis and ranged from 0 to 392 per mm2. Tumour-associated tissue eosinophilia was classified according to intensity as mild, moderate, or intense and correlated statistically to the intensity of the mononuclear inflammatory infiltrate as well as to the location of the eosinophilic inflammatory infiltrate. The multivariate analysis demonstrated that intense tumour-associated tissue eosinophilia is an independent favourable prognostic factor for oral squamous cell carcinomas. CONCLUSION: These findings suggest an anti-tumoral role of eosinophils not as yet well understood that should be better investigated.

Adult↗

PubMed2002

Salivary duct carcinoma: cytokeratin 14 as a marker of in-situ intraductal growth.

AIMS: The aim of this study was to determine the immunoprofile of salivary duct carcinoma and to differentiate intraductal growth from invasive growth. METHODS AND RESULTS: We applied a panel of antibodies (cytokeratins 7, 8, 13, 14, 19, vimentin and alpha-smooth muscle actin) in five cases of salivary duct carcinoma. This panel is currently used for identification of different components of salivary gland tumours in our laboratory. All tumour cells were positive for cytokeratins 7 and 8. Few neoplastic structures expressed cytokeratin 14 in cells surrounding tumour islands. CONCLUSION: The finding of cytokeratin 14 was important to confirm the in-situ intraductal growth, which probably characterizes this low-grade neoplasm.

Adenocarcinoma↗

PubMed2002

Juvenile intraoral pleomorphic adenoma: report of five cases and review of the literature.

The aim of this study is to report on five cases of intraoral pleomorphic adenoma (PA) in patients under 18 years of age and to review the literature. Intraoral salivary gland tumours were reviewed in two Brazilian institutions and five cases of PA in patients under 18 years of age were found. Clinical data were obtained from the medical records and paraffin-embedded tissues were sectioned for proliferating cell nuclear antigen (PCNA) and p53 immunohistochemical analysis. Four patients were female and one was male; two cases affected the palate, two the upper lip and one the tongue. All five patients were treated surgically and after long follow-up periods no recurrences were observed. Tumour cells were weakly positive for PCNA and negative for p53. PA should be considered in the differential diagnosis of submucosal nodules in young patients. In youngsters, PA seems to have similar biological characteristics as in adults, with low recurrence rates after surgical resection.

Adenoma, Pleomorphic↗

PubMed2002

Effects of tracheotomy on respiratory mechanics in spontaneously breathing patients.

Tracheotomy is a method of intubating the trachea, which is employed in several clinical settings, including the treatment of head and neck neoplasms. Tracheotomy is believed to facilitate weaning through changes in respiratory mechanics. Existing information concerning functional changes associated with tracheotomy are limited to comparisons with orotracheal intubation. In this study, respiratory mechanics were monitored in seven spontaneously breathing patients, before and after an elective tracheotomy was performed for surgical treatment of cancer. Campbell diagrams were constructed by plotting pressure, obtained with an oesophageal balloon catheter, against volume, obtained from a pneumotachograph placed at the airway opening. Work of breathing was calculated as the internal area of the Campbell diagram and was partitioned into its elastic and inspiratory and expiratory resistive components. Oesophageal pressure was also used to quantify intrinsic positive end-expiratory pressure (PEEPi) and the pressure-time product (PTP), which is considered to be proportional to the oxygen cost of breathing. PTP was divided into its resistive and elastic components. Inspiratory resistive work, PEEPi, inspiratory PTP, as well as its resistive and elastic components were significantly reduced by tracheotomy. Tracheotomy significantly reduces work of breathing and pressure-time product in spontaneously breathing patients.

Aged↗

PubMed2001

hOGG1 exon7 polymorphism and gastric cancer in case-control studies of Japanese Brazilians and non-Japanese Brazilians.

Polymorphism of hOGG1 may be capable of serving as a genetic marker for individual susceptibility to various cancers because of its role in the repair of oxyradical DNA damage. We examined the distribution of the hOGG1 Ser326Cys polymorphism and its presumed correlation with gastric cancer risk in two case-control studies of different ethnic groups in São Paulo, Brazil. Potentially eligible Japanese (JB) and non-Japanese Brazilian (NJB) case subjects were defined as patients with newly diagnosed malignant neoplasms of the stomach in 13 hospitals in São Paulo. Ninety-six JBs and 236 NJBs were adopted as subjects. Two controls were matched for each JB case, and one control for each NJB case. The subjects were interviewed using a questionnaire and their blood samples were collected. A significant difference in the distribution of this polymorphism between the two ethnic groups was observed (chi(2)=58.3, P<0.01). The mutant type (Ser/Cys or Cys/Cys) was predominant (approximately 65%) in the JBs, but was only present in approximately 40% of the NJBs. Logistic regression analysis showed no significant increased risk for either the Ser/Cys or Cys/Cys type in either group. The odds ratios of the Cys allele for gastric cancer were 1.01 (95% confidence interval (CI): 0.52-1.93) in the JBs and 0.85 (95% CI: 0.57-1.26) in the NJBs. In the NJBs, a significant increased risk of smoking was shown only in the Ser/Ser type, and no increased risk was shown in the genotypes with the Cys allele. However, no statistically significant interactions were observed with smoking or other possible confounding factors. No statistically significant difference in the distribution of the polymorphism was observed between the intestinal type and diffuse type of gastric cancer in either the JBs or the NJBs. The ethnic difference in hOGG1 Ser326Cys polymorphism was much greater than the case-control difference, and this polymorphism is unlikely to be associated with gastric cancer.

Aged↗

PubMed2001

Circulating tumor-derived DNA may permit the early diagnosis of head and neck squamous cell carcinomas.

A series of eight microsatellite loci were assayed for both loss of heterozygosity and new mutated alleles in 91 head and neck squamous cell carcinomas. In 58 cases, alterations were detected and used as markers for assaying the presence of circulating tumor-derived DNA in the patients' plasma. This was unambiguously detected in 17 cases. The probability of detecting circulating DNA was independent of tumor stage and was found to be present even in some individuals with stage I tumors. The presence of such DNA, however, could not be correlated with disease outcome or other significant clinical parameters, suggesting that it has no prognostic significance. The results indicate that circulating tumor-derived DNA could be used as a means of early diagnosis of head and neck tumors.

Alleles↗

PubMed2001

Multivariate analysis of risk factors for neck metastases in surgically treated parotid carcinomas.

OBJECTIVE: To analyze risk factors for neck metastases in patients with parotid carcinomas. DESIGN: Cohort of patients followed up from 1 to 366.2 months at a single institution. SETTING: Referral center, private or institutional practice, hospitalized care. PATIENTS: A total of 145 patients with parotid carcinomas with complete clinical and pathological information. The histological diagnosis was reviewed according to the World Health Organization classification for salivary gland tumors. INTERVENTION: Patients were treated by surgery alone (62 cases) or with postoperative radiotherapy (83 cases). A neck dissection was performed in 80 patients. MAIN OUTCOME MEASURE: Rates of neck lymph node metastasis. Univariate and multivariate analyses were carried out using logistic regression evaluating the significance of demographic, clinical, and pathological data. RESULTS: The following variables were significantly associated to the risk of lymph node metastasis by univariate analysis: histological type (P<.001), T stage (P<.001), desmoplasia (P = .001), facial palsy (P = .02), perineural invasion (P = .01), extraparotid tumor extension (P = .02), and necrosis (P = .003). By multivariate analysis, histological type (P<.001), T stage (P = .03), and desmoplasia (P = .006) had the highest correlation with lymph node metastasis. CONCLUSION: The significant risk factors for neck metastasis in parotid carcinoma were histological type (ie, adenocarcinoma, undifferentiated carcinoma, high-grade mucoepidermoid carcinoma, squamous cell carcinoma, and salivary duct carcinoma), T stage (T3 and T4), and desmoplasia (severe).

Adenocarcinoma↗

PubMed2001

Transforming growth factor beta1, urokinase-type plasminogen activator and plasminogen activator inhibitor-1 mRNA expression in head and neck squamous carcinoma and normal adjacent mucosa.

BACKGROUND: A balance between urokinase-type plasminogen activator (uPA) and its main inhibitor type-1 (PAI-1) appears to be important for cancer invasive behavior. Since uPA/PAI-1 system seems to be regulated by transforming growth factor beta1 (TGFbeta1) in different cell types, our aim was to investigate the relationship between the expression of the three genes and lymph node status in head and neck squamous cell carcinomas (HNSCC) at specific sites. MATERIALS AND METHODS: uPA, PAI-1, and TGFbeta1 mRNAs were determined by Northern analysis in tumor, and paired normal mucosa samples were obtained from 91 operable HNSCC patients. RESULTS: In oral cavity, excluding tongue, TGFbeta1, PAI-1, and uPA mRNAs values were consistently lower in the normal tissues than in tumors. In larynx tumors, TGFbeta1 expression was increased, but no statistically significant differences were found for uPA or PAI-1 mRNAs as compared with normal tissues. Tongue tumors overexpressed only uPA mRNA, and uPA levels showed significant parallel variations with TGFbeta1 and PAI-1 mRNAs mainly in pN+ tumors. In oral cavity tumors, an inverse correlation between TGFbeta1 and uPA was observed in pN0 subgroup, elevated uPA mRNA was counterbalanced by high PAI-1 mRNA TGFbeta1, and PAI-1 were not coordinately expressed. Correlations between the three markers were not found in larynx. Hypopharynx tumors, all staged as pN+, expressed the lowest TGFbeta1 mRNA mean values. CONCLUSIONS: Combined information about TGFbeta1, uPA, and PAI-1 mRNAs may add some clues to the understanding of the pathophysiological role of uPA system in head and neck squamous cell carcinoma.

Adult↗