Biomedical subjects

A Wygoda

Publications and source records attributed to A Wygoda.

6 recordsLinked to original sources

PubMed2000

[Prognostic factors in radiotherapy for hypopharyngeal cancer].

This paper presents influence of selected prognostic factors on results of hypopharyngeal cancer radiotherapy used as only treatment in 97 patients irradiated in Centre of Oncology-Institute in Gliwice between 1980-1987. One-variant analysis showed statistically significant influence of gender, decrease of haemoglobin level during radiotherapy and higher T and N stages. Multivariant analysis demonstrated, that only locoregional status and treatment time has decisive importance on radiotherapy results. Thus, better results of treatment depend on lower T and N stages and correct radiotherapy time.

Adult↗

PubMed2000

[[Radical radiotherapy in patients with laryngeal cancer in clinical material of Institute Oncology in Gliwice treated in year 1990-1996].

This paper presents influence of selected prognostic factors on results of laryngeal cancer radiotherapy used as the only treatment in 541 patients irradiated in Centre of Oncology-Institute in Gliwice between 1990-1996. The 3-year actuarial disease-free survival was 47.5% for supraglottic cancer and 67% for glottic cancer. Primary tumour localisation in glottis correlates with more favourable prognosis than that in supraglottic. For extralaryngeal involvement the most favourable prognosis was infiltration of cartilages and the worst one for the hypopharyngeal and oropharyngeal involvement. Pretreatment tracheostomy significantly correlates with the worst results.

Adult↗

PubMed2000

[Head and neck lymph node metastases from unknown primary site].

The aim of this paper was to evaluate the group of 50 patients with cervical nodes metastases from unknown primary site treated between 1980-1995 in Maria Sk_odowska-Curie Memorial Institute of Oncology in Gliwice. There were 42 males and 8 females ranging in age from 26 to 85 years (median 60). 24 patients underwent combined therapy (surgery with postoperative radiotherapy), 22 underwent radiotherapy. Only 4 patients were treated with surgery alone. 3-years DFS rates were 59% in group treated with combined method, and 10% in group treated only with radiation therapy (p = 0.003). After a median follow up of 39 months 10 primary tumors were discovered--8 in head and neck region, 2 in lower respiratory tracts. DFS rate in group with discovered primary tumors was 40%.

Adult↗

PubMed2000

[Comparison of natural history of squamous cell carcinoma and nondifferentiated carcinoma localized in oro- and nasopharynx].

Aim of this study is comparison of natural history between two subtypes of cancer: squamous and undifferentiated, which were localised in oro- and nasopharynx. Analysis has contained 175 patients with undifferentiatied and 510 patients with squamous cell cancers of oro- and nasopharynx, who were treated in Centre of Oncology--Institute branch Gliwice in 1980-1998. Presence of undiferentiated subtypes were bounded with shortening time of presence the symptoms of disease, most frequent exophytic type of infiltration than in squamous cancer with ulcerative--necrotic type of infiltration. Higher aggressiveness of undifferentiated cancer is based on higher frequency of distant and nodal metastases, metastases to contralateral nodes and higher percentage of conglomerates.

Carcinoma↗

PubMed1999

The effect of patient position and treatment technique in conformal treatment of prostate cancer.

PURPOSE: The relative value of prone versus supine positioning and axial versus nonaxial beam arrangements in the treatment of prostate cancer remains controversial. Two critical issues in comparing techniques are: 1) dose to critical normal tissues, and 2) prostate stabilization. METHODS AND MATERIALS: Ten patients underwent pretreatment CT scans in one supine and two prone positions (flat and angled). To evaluate normal tissue exposure, prostate/seminal vesicle volumes or prostate volumes were expanded 8 mm and covered by the 95% isodose surface by both 6-field axial and 4-field nonaxial techniques. A total of 280 dose-volume histograms (DVHs) were analyzed to evaluate dose to rectal wall and bladder relative to patient position and beam arrangement. A CT scan was repeated in each patient after 5 weeks of treatment. Prostate motion was assessed by comparing early to late scans by three methods: 1) center of mass shift, 2) superior pubic symphysis to anterior prostate distance, and 3) deviation of the posterior surface of the prostate. RESULTS: For prostate (P) or prostate/seminal vesicle (P/SV) treatments, prone flat was advantageous or equivalent to other positions with regard to rectal sparing. The mechanism of rectal sparing in the prone position may be related to a paradoxical retraction of the rectum against the sacrum, away from the P/SV. Although there was no clear overall preference for beam arrangement, substantial improvements in rectal sparing could be realized for individual patients. In this limited number of patients, there was no convincing evidence prostate position was stabilized by prone relative to supine position. CONCLUSIONS: Prone flat positioning was advantageous over other positions and beam arrangements in rectal sparing. This study suggests that patient position is a more critical a factor in conformal therapy than beam arrangement, and may improve the safety of dose escalation.

Humans↗

PubMed1999

Clinical radiobiology of glottic T1 squamous cell carcinoma.

PURPOSE: Radiation therapy is the treatment of choice for early glottic squamous cell cancer in many institutions over the world. Despite a relatively homogenous clinical model of T1 glottic tumors for the fractionation studies, the relationships between dose-time parameters remain unclear. To analyze the influence of fractionation parameters and hemoglobin level on tumor cure, this study has been performed. MATERIALS AND METHODS: This is a retrospective review of 235 patients with T1N0M0 glottic cancer treated by radiation therapy alone given in a conventional schedule with 5 fractions each week. The individual total dose, dose per fraction, and overall treatment time (OTT) ranged from 51-70 Gy, 1.5-3.0 Gy, and 24-79 days, respectively. The median follow-up was 48 months. Patient data--total dose, dose per fraction, OTT, and hemoglobin level (Hb) measured before the radiation treatment--were fitted by the mixed LQ/log-logistic model. RESULTS: The 5-year local relapse-free survival rate was 84%. All parameters included in the mixed LQ/log-logistic model improved the fit significantly. The dose-response curve for 235 patients with T1 glottic cancer was well defined and steep, and showed significant decrease in tumor control probability (TCP) when total doses were below 61 Gy. The 10-day prolongation of OTT, from 45 to 55 days, decreased the TCP by 13%. The dose of 0.35 Gy/day, compensated repopulation during the 1 day of prolongation, which indicates a potential doubling time (Tpot) for glottic T1 tumor clonogens of 5.5 days. The drop of Hb level of 1 g/dl (from 13.8 g/dl to 12.8 g/dl) gave a 6% decrease of TCP, provided that OTT was 45 days. CONCLUSION: The significant correlation between the total dose, overall treatment time, hemoglobin concentration, and tumor control probability has been found for T1 glottic cancer.

Carcinoma, Squamous Cell↗