Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Maciej Tytor is active.

Publication


Featured researches published by Maciej Tytor.


Acta Oto-laryngologica | 1992

Prognostic Factors in Oral Cavity Carcinomas

Maciej Tytor; Jan Olofsson

This retrospective study of 176 patients with oral cavity carcinoma showed that nearly 60% of the patients presented with an advanced stage of disease. The duration of symptoms was shorter in patients with a large tumour than with a small (p less than 0.001) and in patients with metastases than in those without (p less than 0.01). Lymph node metastases were more common in large tumours (p less than 0.01), in tumours with high malignancy grading (p less than 0.05) and in non-diploid tumours (p less than 0.001). The presence of lymph node metastases (p less than 0.001), tumour size (p less than 0.01) and tumour DNA ploidy (p less than 0.005) were the only parameters that significantly influenced survival (Cox regression analysis).


Acta Oncologica | 1996

Primary Radiotherapy of Tl and T2 Glottic Carcinoma: Analysis of treatment results and prognostic factors in 223 patients

Claes Klintenberg; Jan Lundgren; Gunnar Adell; Maciej Tytor; Lena Norberg-Spaak; Rolf Edelman; John Carstensen

Treatment results in 223 patients with T1 and T2 glottic carcinoma were analysed. A multivariate analysis was performed to evaluate the prognostic significance of factors related to tumour, patient and treatment. Locoregional control after radiotherapy was 90% for 129 patients with T1 tumours and 73% for 94 with T2 tumours. Disease-specific survival was 96% and 81% for patients with T1 and T2 tumours, respectively. In the multivariate analysis of locoregional control, subglottic extension contributed prognostic information to T-stage. In the univariate analysis, number of involved tumour sites, cord mobility and treatment interruption had a significant influence, which was lost in the multivariate analysis. Age gave additional prognostic information in the multivariate analysis of disease-specific survival. Significant adverse effects of radiotherapy were found in 9 patients (4%). Forty-nine patients (22%) had a second malignancy, 11 (5%) diagnosed before the glottic carcinoma.


Pathology Research and Practice | 1991

Heterogeneity of Squamous Cell Carcinomas of the Oral Cavity Studied by Flow Cytometry

Maciej Tytor; S. Wingren; J. Olofsson

The DNA pattern was determined by flow cytometry in 76 samples from 16 squamous cell carcinomas of the oral cavity to assess intratumour DNA heterogeneity. Heterogeneous DNA content was found in 2 tumours (12%); both containing DNA diploid and DNA aneuploid cell clones. The remaining 14 tumours showed a homogeneous DNA distribution in the different specimens; 9 (56%) were diploid, 3 (19%) aneuploid and 2 (12%) were polyploid. The DNA non-diploid tumours were clinically more advanced than the DNA diploid ones (p less than 0.05). The tumour proliferation rate (fraction of cells in S-phase) was higher in aneuploid tumours than in diploid ones (p less than 0.01).


Pathology Research and Practice | 1987

DNA Pattern in Oral Cavity Carcinomas in Relation to Clinical Stage and Histological Grading

Maciej Tytor; G. Franzén; J. Olofsson

Cytofluorometric DNA analysis was performed in 88 squamous cell carcinomas of the oral cavity. 48% (42/88) of the tumours were DNA non-diploid. The frequency of DNA non-diploid tumours seemed to correlate with the increasing size of the tumour, and the decrease of histological grading, and certainly with the presence of lymph node metastases (p less than 0.001). DNA non-diploid tumours often had shorter duration of symptoms. The S-phase level seemed to increase the less differentiated the tumour but did not correlate either to tumour size or to duration of symptoms. Polyploid nuclei were more common in poorly differentiated tumours (9/10) as compared to well differentiated ones (17/33) (p less than 0.05) and seemed to be more common in tumours with metastases (20/26) than in those without (40/62).


Acta Oncologica | 1987

Preoperative Irradiation in Oral Cavity Carcinoma: A study with special reference to DNA pattern, histological response and prognosis

G. Franzean; Jan Olofsson; Maciej Tytor; Claes Klintenberg; B. Risberg

The relation between DNA pattern and response to preoperative radiotherapy was studied in 51 patients with oral squamous cell carcinomas operated 4 weeks after irradiation. Small tumors (T1 and T2) showed more pronounced response to radiotherapy than larger ones (T3 and T4), as did DNA aneuploid tumors. Eight of 11 DNA aneuploid tumors showed no remaining tumor in the operation specimen, compared to 6 of 21 DNA polyploid and 2 of 19 DNA diploid tumors. None of 16 patients without demonstrable remaining cancer in the operation specimen had local recurrence. The presence of lymph node metastases was the most important prognostic factor.


Operations Research Letters | 1985

Complications in Neck Dissection

J. Olofsson; Maciej Tytor

Complications following 186 neck dissections in 171 patients are reported. Major surgical complications occurred after 8 neck dissections; minor surgical after 52 and medical complications after 13. Preoperative radiotherapy did not seem to influence the complication rate. 16 of 21 patients with recurrences in the neck had extranodal spread histologically. 76% of the recurrences occurred within a year and proved fatal in nearly all patients. Preservation of the spinal accessory nerve did not increase the recurrence rate.


Operations Research Letters | 1991

Polymorphous Low-Grade Adenocarcinoma: A ‘New’ Salivary Gland Tumour

Henrik B. Hellquist; Maciej Tytor

We describe the clinicopathological features of polymorphic low-grade adenocarcinoma. The hallmarks of cytologic uniformity, remarkable histologic diversity, and favourable prognosis are emphasized. Polymorphous low-grade adenocarcinoma is not listed in the existing WHO classification, but recent reports indicate that it may be the second most common malignant intraoral salivary gland tumour. Both pathologists and ENT surgeons, who are not specialized in salivary gland tumours, may not be familiar with this tumour entity, and polymorphous low-grade adenocarcinoma therefore merits a detailed description.


Acta Oto-laryngologica | 1999

DNA Analysis of Malignant Salivary Gland Carcinomas: Comparison of Different Tissue Preparations and Measuring Techniques

Ståle Nordgård; Gunnar Franzén; Morten Boysen; Maciej Tytor

This study correlates static and flow-cytometric analysis on paraffin-embedded and fresh material of salivary gland carcinomas. Nuclear suspensions for DNA analysis were prepared from paraffin-embedded and fresh material. Comparison of the results of static and flow cytometry on paraffin-embedded material revealed no significant correlation between DNA ploidy and S-phase value. The coefficients of variation were significantly lower for static than for flow cytometry (p < 0.05). Flow-cytometric analysis on fresh and paraffin-embedded material correlated well concerning DNA ploidy, but not for the S-phase. The coefficients of variation were significantly lower for the fresh than for the paraffin-embedded material (p < 0.001). Cytometric analysis on paraffin-embedded material of malignant salivary gland carcinomas should be critically evaluated. There is a need for flow-cytometric investigations on fresh material to clarify further the prognostic value of this method.


Clinical Otolaryngology | 1990

Squamous cell carcinoma of the oral cavity. A review of 176 cases with application of malignancy grading and DNA measurements.

Maciej Tytor; Jan Olofsson; T. Ledin; U. Brunk; C. Klintenberg


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 1989

DNA ploidy in oral cavity carcinomas, with special reference to prognosis

Maciej Tytor; Gunnar Franzén; Jan Olofsson

Collaboration


Dive into the Maciej Tytor's collaboration.

Top Co-Authors

Avatar

Jan Olofsson

Haukeland University Hospital

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Ronald T. Grenko

Pennsylvania State University

View shared research outputs
Top Co-Authors

Avatar

Gunnar Franzén

Norwegian University of Science and Technology

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Ståle Nordgård

Norwegian University of Science and Technology

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge