Serum levels of AFP, CEA, hCG, hPL and SP₁ were measured by specific radioimmunoassays in 111 patients with testicular germ cell tumors. Seminomas, mature teratomas and ‘pure type’ embryonal carcinomas, as well as the latter two types of tumor with seminomatous admixture, do not produce markers unless in advanced stages when they may do so (small amounts of hCG, hPL and SP₁). Tumors composed of yolk-sac elements alone or mixed with embryonal carcinoma produce AFP; of syncytiotrophoblastic elements – hCG, hPL or SP₁; and teratomas with differentiated structures- CEA. Compound tumors can produce any of the five markers. When present in serum after orchiectomy or lymphadenectomy, the markers are useful both in diagnosis of the tumor elements that metastasized and in staging; whereas their absence does not exclude regional or distant metastases which may contain only marker-negative elements, e.g., due to changes in tumor histology. Measurement of the serum levels of the markers informs about the remaining regional tumor elements or latent metastases and therefore is more useful than immunoperoxidase staining which provides information on the already dissected structures only.

61 patients with seminoma and 113 with nonseminomatous germ cell tumors of the testis were treated according to the histology, stage of disease, and serum levels of tumor markers (CEA, AFP, hCG, hPL and SP₁). 33 were stage I, 63 stage II, and 78 stage III patients. Most patients with seminoma, mature teratoma, immature teratoma, and ‘pure type’ embryonal carcinoma, as well as the latter three types with seminomatous admixture, had normal serum levels of the markers. Sometimes, slightly elevated levels of hCG suggested the presence of metastases. But, serial measurements of the markers were seldom useful in monitoring therapy. The 5-year tumor-free survival rates were favorable: 100% for stage I and II disease; and 57 or 44% for, respectively, stage III seminoma or the other tumors amounting to 10% of the nonseminomatous group. The role of the five markers was significant in patients with teratoma with malignant transformation, choriocarcinoma, endodermal sinus tumor (EST), and embryonal carcinoma or teratocarcinoma with an admixture of EST or choriocarcinoma or both. Elevation of a marker was a grave prognostic sign. The 5-year survival rates were 100, 16, and 4% for stages I, II and III disease, respectively. An elevated level of one or more of the markers assayed was always useful for monitoring therapy. Decreasing level indicated regression. However, return of an elevated level to normal did not indicate eradication of all tumor and called for diagnosis by imaging modalities. Constantly elevated or increasing marker levels during treatment indicated resistance to therapy. An increasing level from any nadir during remission indicated recurrence. Elevated levels of any of the five markers tested were as important as imaging modalities, and often more sensitive.

Introduction. The paper presents an original, used in our Institute, method of lung volume irradiation in patients with pneumonia during COVID-19 infection. Material and methods. Procedures such as the simulation of treatment and radiotherapy are performed in a treatment room. Real time radiation treatment planning is realized as 2D planning (Irreg Planning VMS) in a separate room, and the 3D (eclipse VMS) dose distribution is calculated after the treatment. During radiation exposure, a fluence map is measured. Results. A method of irradiating the lungs of patients with COVID-19 was developed, which allows to shorten the time the patient is on the treatment table and minimize contacts between the patient and staff. Conclusions. The presented procedure made it possible to minimize the time of patient's stay in the radiotherapy department and at the same time, it retains all the required quality assurance procedures in radiotherapy treatment.

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Introduction: One of many procedures to control the quality of radiotherapy is daily imaging of the patient’s anatomy. The CBCT (Cone Beam Computed Tomography) plays an important role in patient positioning, and dose delivery monitoring. Nowadays, CBCT is a baseline for the calculation of fraction and total dose. Thus, it provides the potential for more comprehensive monitoring of the delivered dose and adaptive radiotherapy. However, due to the poor quality and the presence of numerous artifacts, the replacement of the CBCT image with the corrected one is desired for dose calculation. The aim of the study was to validate a method for generating a synthetic CT image based on deformable image registration.Material and methods: A Head & Torso Freepoint phantom, model 002H9K (Computerized Imaging Reference Systems, Norfolk, USA) with inserts was imaged with CT (Computed Tomography). Then, contouring and treatment plan were created in Eclipse (Varian Medical Systems, Palo Alto, CA, USA) treatment planning system. The phantom was scanned again with the CBCT. The planning CT was registered and deformed to the CBCT, resulting in a synthetic CT in Velocity software (Varian Medical Systems, Palo Alto, CA, USA). The dose distribution was recalculated based on the created CT image.Results: Differences in structure volumes and dose statistics calculated both on CT and synthetic CT were evaluated. Discrepancies between the original and delivered plan from 0.0 to 2.5% were obtained. Dose comparison was performed on the DVH (Dose-Volume Histogram) for all delineated inserts.Conclusions: Our findings suggest the potential utility of deformable registration and synthetic CT for providing dose reconstruction. This study reports on the limitation of the procedure related to the limited length of the CBCT volume and deformable fusion inaccuracies.