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Dive into the research topics where Wojciech Michalski is active.

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Featured researches published by Wojciech Michalski.


Acta Oncologica | 1996

Risk Factors for Central Nervous System Involvement in Non-Hodgkins-Lymphoma a multivariate analysis

Nina Keldsen; Wojciech Michalski; Søren M. Bentzen; Knud Bendix Hansen; Karen Thorling

A consecutive cohort of patients with NHL was examined to identify the factors predictive of CNS-involvement with Coxs proportional hazards model in a multivariate analysis. Twenty-seven cases of CNS-involvement were found among 498 patients with NHL. Only 3 of 96 patients with low-grade lymphomas had CNS involvement, all occurring after transformation into high-grade lymphoma. In univariate analysis of 402 patients with intermediate or high-grade lymphoma, lymphoblastic histology (including Burkitts lymphoma), age <35 years, B-symptoms, stage IV disease, testis involvement and bone marrow involvement were found to be statistically significant risk factors. Lymphoblastic histology was found to be strongly correlated to age younger than 35 years. In the multivariate analysis only lymphoblastic histology, stage IV disease and B-symptoms were found to be significantly associated with CNS involvement. It is concluded that CNS prophylaxis should be considered in all patients with lymphoblastic histology and in patients with stage IV B lymphomas other than those of low-grade types.


Annals of Oncology | 2013

Palliative radiotherapy and chemotherapy instead of surgery in symptomatic rectal cancer with synchronous unresectable metastases: a phase II study.

D. Tyc-Szczepaniak; Lucjan S. Wyrwicz; Lucyna Kepka; Wojciech Michalski; M. Olszyna-Serementa; Jakub Pałucki; Lucyna Pietrzak; A. Rutkowski; Krzysztof Bujko

BACKGROUNDnIn stage IV rectal cancer, palliative surgery is often carried out upfront. This study investigated whether the surgery can be avoided.nnnPATIENTS AND METHODSnForty patients with symptomatic primary rectal adenocarcinoma and synchronous distant metastases deemed to be unresectable received 5 × 5 Gy irradiation and then oxaliplatin-based chemotherapy. Before treatment, 38% of patients had a near-obstructing lesion. The palliative effect was evaluated by questionnaires completed by the patients.nnnRESULTSnThe median follow-up for living patients was 26 months (range 19-34). The median overall survival was 11.5 months. Eight patients (20%) required surgery during the course of their disease: seven patients required stoma creation and one had local excision. Thirty percent of patients had a complete resolution of pelvic symptoms during the whole course of the disease, and 35% had significant improvement. In the subgroup with a near-obstructing lesion, 23% of patients required stoma creation. In all patients, the probability of requiring palliative surgery at 2 years was 17.5% [95% confidence interval (CI) 13% to 22%), and the probability of sustained good palliative effect after radiotherapy and chemotherapy was 67% (95% CI 58% to 76%).nnnCONCLUSIONnShort-course radiotherapy and chemotherapy allowed most patients to avoid surgery, even those with a near-obstructing lesion.nnnCLINICALTRIALSnThe trial is registered with ClinicalTrials.gov: number NCT01157806.


European Journal of Cancer | 1996

Prophylactic cranial irradiation in limited stage small cell lung cancer: Survival benefit in patients with favourable characteristics

E. Work; Søren M. Bentzen; Ole Steen Nielsen; Kirsten Fode; Wojciech Michalski; T. Palshof

The value of prophylactic cranial irradiation (PCI) in the treatment of small cell lung cancer (SCLC) remains controversial. As part of a randomised study investigating the timing of chest irradiation (CI) with respect to combination chemotherapy, the effect of PCI was evaluated. Between 1981 and 1989, patients were randomised to initial chest irradiation ICI (99 patients) or 18 weeks delayed late chest irradiation LCI (100 patients). PCI was given to 157 patients. In the beginning, only ICI patients received PCI, but in October 1984 the strategy was changed so that all patients received PCI. Thus, the patients who did not receive PCI were randomly allocated. The PCI dose was 33 Gy/11 fractions (45 patients) and 25 Gy/11 fractions (112 patients). The 2-year CNS-recurrence rate (+/- standard error) was significantly lower in patients who received PCI, 16.3 +/- 4.1%, than in those who did not, 55.1 +/- 12.4% (p = 0.01). In contrast, the 2-year cause-specific survival was not significantly different, 24.9 +/- 3.6% and 16.9 +/- 6.2% (p = 0.31). The 2-year progression-free rates with or without PCI were 18.5 +/- 3.3% and 11.4 +/- 5.4%, respectively (p = 0.58). To test the hypothesis that a benefit from PCI would mainly be expected among the patients with the best prognosis, a multivariate regression analysis of prognostic factors was undertaken. Based on weight loss, performance status, serum sodium and age, the third of the patients with the best prognosis were identified. In that group of patients, the survival advantage from PCI was statistically significant, 35.5 +/- 7.2% versus 14.1 +/- 8.0%, P = 0.029. These results are currently being tested in a Danish multicentre trial where patients with a good prognosis are randomised either to receive PCI or not to receive PCI.


Acta Oncologica | 2016

Palliative radiotherapy and chemotherapy instead of surgery in symptomatic rectal cancer with synchronous unresectable metastases: long-term results of a phase II study.

Dobromira Tyc-Szczepaniak; Lucjan Wyrwicz; Katarzyna Wiśniowska; Wojciech Michalski; Lucyna Pietrzak; Krzysztof Bujko

Dobromira Tyc-Szczepaniak, Lucjan Wyrwicz, Katarzyna Wi sniowska, Wojciech Michalski, Lucyna Pietrzak and Krzysztof Bujko Department of Radiotherapy, Maria Skłodowska-Curie Memorial Cancer Centre, Warsaw, Poland; Clinical Oncology Division of Department of Gastrointestinal Oncology, Maria Skłodowska-Curie Memorial Cancer Centre, Warsaw, Poland; Department of Clinical Trials and Biostatistics Unit, Maria Skłodowska-Curie Memorial Cancer Centre, Warsaw, Poland


Endocrine Practice | 2017

GROWTH RATE OF PARAGANGLIOMAS RELATED TO GERMLINE MUTATIONS OF THE SDHX GENES

Ilona Michałowska; Jarosław B. Ćwikła; Wojciech Michalski; Lucjan S. Wyrwicz; Aleksander Prejbisz; Małgorzata Szperl; Dawid Nieć; Hartmut P. H. Neumann; Andrzej Januszewicz; Mariola Pęczkowska

OBJECTIVEnThe purpose was to determine the growth rate of succinate dehydrogenase subunit (SDHx) gene-related paragangliomas based on computed tomography (CT) measurements.nnnMETHODSnTwenty-seven patients with SDHx mutations who underwent subsequent CT examinations were enrolled in the study. Tumors were classified as head and neck (HNP), thoracic, or abdominal/pelvic paragangliomas (PGLs). The percentage volume increase and volume doubling time were estimated.nnnRESULTSnWe analyzed 56 PGLs (21 with SDHD, 6 with SDHB mutations) in 27 patients (16 men, 11 women; mean age 37.7 years). The estimated median of the follow-up was 23 months. Twenty-two (39.3%) PGLs were located in the abdomen, 8 (14.3%) in the thorax, and 26 (46.4%) in the head and neck region. The median volume growth rate was estimated at 10.4% per year (interquartile range [IQR]: -1.3; 36.3). The volume doubling time was estimated as 7.01 (2.24;+∞) years. By tumor site, the estimated medians of the annual volume growth rates were 13.6% (IQR:0.8 -30.4) for HNP, -6.06% (IQR: -1.79;47.32) for thoracic PGLs, and 10.5% (IQR: -2.2;44.6) for abdominal PGLs. The volume doubling time was 5.44 years (2.61; 87.0) for HNP, 11.8 years (1.79;+∞) for thoracic PGLs, and 6.94 years (1,88;+∞) for abdominal PGLs. There was no significant difference in the volume growth rate according to tumor location or initial size (P>.7 and P = .07, respectively) or gene mutation type (SDHB vs. SDHD, P>.8).nnnCONCLUSIONnPGLs related to SDHx mutations are slowly growing tumors. There were no correlations between tumor location, growth rate or initial size over a 23-month follow-up period.nnnABBREVIATIONSnCT = computed tomography HNP = head and neck paraganglioma IQR = interquartile range PGL = paraganglioma PPGL = pheochromocytoma and paraganglioma SDH = succinate dehydrogenase.


Radiotherapy and Oncology | 2018

Preoperative radiotherapy and local excision of rectal cancer: Long-term results of a randomised study

Przemysław Wawok; Wojciech Polkowski; Piotr Richter; Marek Szczepkowski; Janusz Olędzki; Ryszard Wierzbicki; Tomasz Gach; Andrzej Rutkowski; Adam Dziki; Leszek Kołodziejski; Rafał Sopyło; Lucyna Pietrzak; Jacek Kryński; Katarzyna Wiśniowska; Mateusz Spalek; Konrad Pawlewicz; Marcin Polkowski; Teresa Kowalska; Krzysztof Paprota; Małgorzata Jankiewicz; Andrzej Radkowski; Justyna Chalubinska-Fendler; Wojciech Michalski; Krzysztof Bujko

BACKGROUND AND PURPOSEnIt is uncertain whether local control is acceptable after preoperative radiotherapy and local excision (LE). An optimal preoperative dose/fractionation schedule has not yet been established.nnnMATERIAL AND METHODSnIn a phase III study, patients with cT1-2N0M0 or borderline cT2/T3N0M0u202f<u202f4u202fcm rectal adenocarcinomas were randomised to receive either 5u202f×u202f5 Gy plus 1u202f×u202f4 Gy boost or chemoradiation: 50.4u202fGy in 28 fractions plus 3u202f×u202f1.8u202fGy boost and 5-fluorouracil with leucovorin bolus. LE was performed 6-8u202fweeks later. Patients with ypT0-1R0 disease were observed. Completion total mesorectal excision (CTME) was recommended for poor responders, i.e. ypT1R1/ypT2-3.nnnRESULTSnOf 61 randomised patients, 10 were excluded leaving 51 for analysis; 29 in the short-course group and 22 in the chemoradiation group. YpT0-1R0 was observed in 66% of patients in the short-course group and in 86% in the chemoradiation group, pu202f=u202f0.11. CTME was performed only in 46% of patients with ypT1R1/ypT2-3. The median follow-up was 8.7u202fyears. Local recurrence incidences and overall survival at 10u202fyears were respectively for the short-course group vs. the chemoradiation group 35% vs. 5%, pu202f=u202f0.036 and 47% vs. 86%, pu202f=u202f0.009. In total, local recurrence at 10u202fyears was 79% for ypT1R1/T2-3 without CTME.nnnCONCLUSIONSnThis trial suggests that in the LE setting, both local recurrence and survival are worse after short-course radiotherapy than after chemoradiation. Because of the risk of bias, a confirmatory study is desirable. Lack of CTME is associated with an unacceptably high local recurrence rate.


Kardiochirurgia i Torakochirurgia Polska/Polish Journal of Thoracic and Cardiovascular Surgery | 2016

Mediastinal paragangliomas related to SDHx gene mutations

Ilona Michałowska; Jaroslaw Cwikla; Aleksander Prejbisz; Paweł Kwiatek; Małgorzata Szperl; Wojciech Michalski; Lucjan S. Wyrwicz; Mariusz Kuśmierczyk; Andrzej Januszewicz; Anna Maciejczyk; Marta Roszczynko; Mariola Pęczkowska

Introduction Paragangliomas (PGLs) related to hereditary syndromes are rare mediastinal tumors. Paragangliomas are caused by mutations in genes encoding subunits of succinate dehydrogenase enzyme (SDH). Aim To evaluate clinical, anatomical and functional characteristics of mediastinal paragangliomas related to SDHx gene mutations. Material and methods Retrospective analysis of 75 patients with confirmed SDHx gene mutations (24 patients with SDHB, 5 SDHC, 46 with SDHD mutations) was performed. Patients underwent evaluation using computed tomography (CT), somatostatin receptor scintigraphy (SRS) (99mTc-[HYNIC,Tyr3]-octreotide), 123I mIBG scintigraphy and urinary excretion of total methoxycatecholamines. Results Out of 75 patients, 16 (21%) patients (1 SDHB, 15 SDHD mutations) had 17 PGLs localized in the mediastinum. Fourteen PGLs were localized in the middle mediastinum (intrapericardial) and 3 PGLs in the posterior mediastinum. The median diameter of paragangliomas measured on the axial slice was 24.3 mm (interquartile range (IQR): 14.7–36.6), and the median volume was 2.78 ml (IQR: 0.87–16.16). Twelve out of 16 patients (75%) underwent SRS, and 11 of them (92.3%) had pathological uptake of the radiotracer. Eleven (68.75%) out of 16 patients underwent 123 I mIBG, with only 3 positive results. Symptoms of catecholamine excretion were observed in 3 patients with PGLs localized in the posterior mediastinum. All PGLs were benign except in 1 patient with the SDHB mutation and PGL detected in the posterior mediastinum, who had a metastatic disease. Conclusions Most mediastinal paragangliomas were related to SDHD gene mutations. They were asymptomatic, localized in the medial mediastinum, intrapericardially.


Medical Oncology | 2018

Testicular teratomas: a growing problem?

Wojciech Michalski; Joanna Jonska-Gmyrek; Grazyna Poniatowska; Jakub Kucharz; Pawel Stelmasiak; Karol Nietupski; Małgorzata Sadowska; Tomasz Demkow; Paweł Wiechno

Testicular teratomas represent a specific entity within the group of germ-cell tumours. They may comprise elements of all three germ layers. In contrast to prepubertal benign teratomas observed in infants and adolescents, postpubertal teratomas originate from the malignant germ-cell precursor. Given the good prognosis and curability of most patients with germ-cell tumour, medical oncologists and urological surgeons must be well acquainted with the principles of teratomas management. Surgery plays the decisive part in teratomas treatment, as these tumours are resistant to radio- and, to some extent, chemotherapy. In this article we concentrate on the management of post-chemotherapy resection of teratomatous masses, with special attention to the phenomenon of ‘growing teratoma syndrome’ and somatic-type transformation of teratomas. To understand the nature of teratomas better, we begin with a glimpse of their biological, molecular and immunohistochemical features. Managing germ-cell tumours, teratomas in particular, in high-volume reference centres is of utmost importance to maintain and increase the survivorship rate in these patients.


Journal of Clinical Oncology | 2018

The prospective assessment of the prostatic cancer mortality with PSA progression in the groups treated or not treated by salvage local brachytherapy.

Karol Nietupski; Anna Kulik; Paweł Wiechno; Tomasz Demkow; Piotr Pęczkowski; Małgorzata Pilichowska; Grazyna Poniatowska; Wojciech Michalski; Joanna Rzymkowska; Małgorzata Sadowska; Marcin Ligaj; Jakub Kucharz; Joanna Jonska-Gmyrek; Ewa Wieczorek; Katarzyna Stencel

85Background: The effectiveness of diagnostics of local recurrence of prostatic adenocarcinoma after radical radiotherapy and local retreatment high definition brachytherapy and its influence on the prostatic cancer survival. Methods: 55 patients with locally advanced prostatic adenocarcinoma with rising PSA level after radical radiotherapy and exclusion of distant metastases underwent prostatic biopsy. ECOG performance status 0-1 were eligible. The histopathological confirmation was obtained in 22 cases, and 33 patients had negative biopsy. In the case of positive biopsy radical salvage brachytherapy was performed in all patients. In the case of negative biopsy definitive anti-androgen therapy was administered in patients with PSA progression. Anti – androgen therapy was performed as adjuvant and neoadjuvant treatment after brachytherapy. In the course of the long (median 108months) observation we assessed prostatic specific mortality in both groups. In addition we assessed time to PSA progression during...


Gynecologic and Obstetric Investigation | 2018

Serous Carcinoma of the Uterine Cervix, an Extremely Rare Aggressive Entity: A Literature Review

Joanna Jonska-Gmyrek; Agnieszka Zolciak-Siwinska; Leszek Gmyrek; Wojciech Michalski; Grazyna Poniatowska; Malgorzata Fuksiewicz; Paweł Wiechno; Jakub Kucharz; Maria Kowalska; Beata Kotowicz

Background/Aims: Serous carcinoma of the uterine cervix (USCC) is an extremely rare subtype. To establish the treatment strategy in patients with USCC is an important issue. Methods: MEDLINE (PubMed) was searched for all articles published after the first publication by Lurie et al. [Eur J Obstet Gynecol Reprod Biol 1991; 40: 79–81], reporting woman diagnosed with USCC. Because of limited numbers of studies on the topic of the study, we could not keep a restriction of eliminating smaller sample sizes. Results: A search of PubMed demonstrated that 113 cases of USCC have been reported in the literature since the first publication. The current treatment modality adopted for early cervical cancer is hysterectomy with bilateral iliac-obturator lymphadenectomy and postoperative radiotherapy (RT) or radiochemotherapy (RT-CT) if risk factors for cervical carcinoma appear. The treatment strategy for locally advanced USCC is preoperative RT-CT or chemotherapy (CHTH) with the intention to treat the patient surgically. The treatment option for disseminated disease is CHTH with paclitaxel and carboplatin. Conclusion: Risk factors and a more advanced clinical stage of USCC have an impact on poor outcomes despite the use of standard treatment methods, adapted for cervical cancer. The outside-pelvic failures tend to seek effective systemic treatment.

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Lucjan S. Wyrwicz

Adam Mickiewicz University in Poznań

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Wojciech Polkowski

Medical University of Lublin

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Jakub Kucharz

Jagiellonian University Medical College

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Ilona Michałowska

Medical University of Warsaw

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