Giant locally advanced and metastatic squamous cell skin carcinoma of head and neck region: case report.

INTRODUCTION: At the present time, the skin tumors are among the most common cancers. Optimal therapy is based on the extent of the disease and the age of the patient. The need for radiotherapy occurs for inoperable locally advanced tumors and in the event of failure, salvage surgery is applied. MATERIALS AND METHODS: We provided a case report of an older patient with giant squamous cell skin carcinoma and a review of published articles. RESULTS: We present a rare case of giant squamous cell skin carcinoma with metastatic satellite tumors that was primarily treated with curative radiotherapy. Five months after radiotherapy, a recurrent tumor was detected at the site of origin and the treatment was completed by salvage surgery. Full remission was achieved for four years. CONCLUSION: Despite the seemingly incurable finding it is always necessary to consider radical treatment regardless of the patient´s age. Curative treatment could achieve long term remission in the group of older patients.

Comparing morbidity and cancer control after 3D-conformal (70/74 Gy) and intensity modulated radiotherapy (78/82 Gy) for prostate cancer.

PURPOSE: The purpose of this work was to compare toxicity and cancer control between patients with prostate cancer treated using three-dimensional conformal radiotherapy (3D-CRT) and those treated using intensity-modulated radiation therapy (IMRT). METHODS AND MATERIALS: A total of 553 patients with prostate cancer were treated with 3D-CRT 70-74 Gy (3D-CRT 70, 3D-CRT 74) or IMRT 78-82 Gy (IMRT 78, IMRT/SIB 82). Late toxicity was scored according to FC-RTOG/LENT criteria. Biochemical failure was defined using the Phoenix and ASTRO definitions. RESULTS: The 5-year risk of grade 2-4 genitourinary toxicity was 26.3 % (3D-CRT 70), 27.2 % (3D-CRT 74), 17.3 % (IMRT 78), and 25.1 % (IMRT/SIB 82) without statistical differences. The 5-year risk of grade 2-4 gastrointestinal toxicity was 19.4 % (3D-CRT 70), 42.1 % (3D-CRT 74), 20.5 % (IMRT 78), and 26.6 % (IMRT/SIB 82). The differences between 3D-CRT 74 and 3D-CRT 70 and between 3D-CRT 74 and IMRT 78 were statistically significant (log rank p = 0.03). The 5-year Phoenix PSA relapse-free survival (PSA-RFS) in low-risk, intermediate-risk, and high-risk patients treated using 3D-CRT were 89.4, 65.5, and 57.8 %, respectively. Patients treated with IMRT achieved the following results: 90.9, 89.4, and 83.9 %. Clinical relapse-free survival (C-RFS) in patients treated using 3D-CRT vs. IMRT for the aforementioned groups were 94.7 vs. 100 %, 86.8 vs. 98.6 %, and 84.4 vs. 94.5 %. Disease-free survival (DFS) for patients treated using 3D-CRT were 83.1, 70.9, and 71.5 %. The IMRT group reached 95.8, 89.1, and 87.6 %. The PSA-RFS for intermediate- and high-risk patients were statistically significant, while C-RFS and DFS were marginally better. CONCLUSION: Dose escalation with IMRT was associated with improved cancer control in intermediate- and high-risk patients in comparison with 3D-CRT, without compromising toxicity.

Interfraction variation in prostate cancer - analysis of 11726 cone-beam CT.

PURPOSE: To investigate the setup margins in prostate cancer treatment without using daily online repositioning methods. METHODS: We analysed the data from patients treated with curative-intend radiotherapy. Each patient underwent a series of pretreatment online localizations during daily setup using conebeam CT. The skin-prostate shifts and bone-prostate shifts were recorded in anteroposterior (AP), craniocaudal (CC), and laterolateral (LL)direction. The safety margins based on van Herk equation (2.5Σ+0.7σ) were calculated and the correlations between margins and various patient characteristics and prostate locations were investigated. RESULTS: A total of 307 patients were included, representing 11,726 localisations resulting in 70,356 shifts. The man skin-prostate setup inaccuracy was 0.8 ± 5.4mm in AP, 1.3 ± 4.8mm for CC, and 0.1 ± 5.6mm in LL direction. The man bone-prostate setup inaccuracy was 0.4 ± 3.3mm in AP, 0.1 ± 2.5mm for CC, and 0.1 ± 1.4mm in LL direction. According to van Herk equation, clinical target volume (CTV)-planning target volume (PTV) margins of 11.4, 10.6, and 11.8 mm (AP, CC, and LL, respectively) would be required for setup using skin markers and margins of 7.0, 4.7, and 2.1mm would be necessary for setup using bone structures. The average rectal area < 11cm(2) and volume of bladder > 300 cm(3) were associated with smaller CTV-PTV margins for setup using bone structures. The largest margins (15.8 mm in LL direction) were needed in patients with body mass index (BMI) > 35 using skin markers. CONCLUSIONS: Our results confirm that the commonly used CTV-PTV margins are inadequate.

Radical prostatectomy in high-grade prostate cancer, salvage and adjuvant radiotherapy.

INTRODUCTION: Prostate cancer with a Gleason score (GS) of 8-10 is linked to a higher risk of recurrence and progression. The aim of this paper is to evaluate treatment results of our high-risk patient cohort. PATIENTS AND METHODS: The cohort of 42 patients with radical prostatectomy (RP) specimen histology GS 8-10 was assessed. The patients were followed up after RP and radiotherapy (RT) was delivered in case of a biochemical relapse. Adjuvant radiotherapy (aRT) was delivered only in case of a positive surgical margin (PSM). The following parameters were evaluated: biochemical progression-free survival (BPFS), overall survival (OS) and cancer-specific survival (CSS). The second objective was to evaluate adverse effects of RP and RT. RESULTS: The median follow-up time was 88 months (18-168). RP led to BPFS in 16 patients (38%). Five patients with PSM underwent aRT and 20 underwent salvage radiotherapy (sRT). One patient died of myocardial infarction and 1 patient died of metastatic disease. Skeletal metastases were recorded in 2 patients. The BPFS in RP combinations with sRT or aRT was reached in 29 patients (69%). The OS and CSS in our cohort reached 95 and 98%, respectively. CONCLUSION: Management with aRT only in PSM was very effective, according to our retrospective study.

Image-guided radiation therapy produces lower acute and chronic gastrointestinal and genitourinary toxicity in prostate cancer patients.

PURPOSE: This paper compares individual radiation therapy techniques used for prostate cancer and their benefits in clinical practice. METHODS: We retrospectively analyzed 921 patients with localized prostate tumors treated between 1997 and 2012. We divided the patients into four groups according to the selected treatment technique (conformal radiation therapy [3DCRT], intensity-modulated radiation therapy [IMRT], image-guided radiation therapy [IGRT], and volumetric-modulated arc therapy [VMAT]) and evaluated the incidence of acute and chronic gastrointestinal (GI) and genitourinary (GU) toxicity. RESULTS: The incidence of grade 2 or greater acute GU and GI toxicity was significantly higher among techniques other than IGRT (p˂0.001). We found the same results in the case of grade 3 or greater acute GU toxicity (p˂0.001). Grade 3 or higher acute GI toxicity occurred only in one patient treated by 3DCRT. Cumulative late GI toxicity of grade 2 or higher and grade 3 or higher was recorded over 3 years significantly more frequently among non-IGRT techniques as compared to IGRT (p˂0.001). As regards GU toxicity, we found significantly higher incidence only for grade 2 or higher (p˂0.001), not for grade 3 or higher. No occurrence of grade 4 toxicity was recorded. The greatest incidence of patients without acute and chronic GI/GU toxicity was recorded in connection with VMAT. CONCLUSION: IGRT demonstrated a pronounced reduction in acute and chronic GU and GI toxicity as compared to non-IGRT techniques in the treatment of localized prostate cancer.

Dose escalation in prostate radiotherapy up to 82 Gy using simultaneous integrated boost: direct comparison of acute and late toxicity with 3D-CRT 74 Gy and IMRT 78 Gy.

PURPOSE: To compare acute and late toxicity after three-dimensional conformal radiotherapy to the prostate to 74 Gy (3D-CRT) with intensity-modulated radiotherapy to 78 Gy (IMRT 78) and IMRT using simultaneous integrated boost to 82 Gy (IMRT/SIB 82). PATIENTS AND METHODS: 94 patients treated with 3D-CRT to the prostate and base of seminal vesicles to 74 Gy represented the first group. The second group consisted of 138 patients subjected to IMRT covering the prostate and base of seminal vesicles to 78 Gy. The last group was treated with IMRT using SIB. The prescribed doses were 82 Gy and 73.8 Gy in 42 fractions to the prostate and seminal vesicles. Late toxicity was prospectively scored according to the RTOG/FC-LENT scale. RESULTS: Acute gastrointestinal toxicity >or= grade 2 occurred in 35.1% of patients treated with 3D-CRT, in 16% subjected to IMRT 78, and in 7.7% receiving IMRT/SIB 82. Acute genitourinary toxicity >or= grade 2 was observed in 26.6% (3D-CRT), 33% (IMRT 78), and 30.7% (IMRT/SIB 82). At 3 years, the estimated cumulative incidence of grade 3 late gastrointestinal toxicity was 14% for 3D-CRT, 5% for IMRT 78, and 2% for IMRT/SIB 82. The difference became significant (log rank p = 0.02). The estimated cumulative incidence of grade 3 late genitourinary toxicity was 9% (3D-CRT), 7% (IMRT 78), and 6% (IMRT/SIB 82) without statistical differences (log rank p = 0.32) CONCLUSION: SIB enables dose escalation up to 82 Gy with a lower rate of gastrointestinal toxicity grade 3 in comparison with 3D-CRT up to 74 Gy.

Late toxicity after conformal and intensity-modulated radiation therapy for prostate cancer: impact of previous surgery for benign prostatic hyperplasia.

OBJECTIVES: To retrospectively compare late toxicity of conventional-dose three-dimensional conformal radiation therapy (3D-CRT) and high-dose intensity-modulated radiation therapy (IMRT) for prostate cancer. METHODS: A total of 340 patients with T1-3 prostate cancer were treated with 3D-CRT (n = 228) and IMRT (n = 112). The median follow-up time was 5.9 years and 3.0 years, respectively. The prescription dose was 70 Gy for 3D-CRT and 78 Gy for IMRT. Late gastrointestinal (GI) and genitourinary (GU) toxicities were graded according to the Fox Chase modification of the Radiation Therapy Oncology Group and Late Effects Normal Tissue Task Force criteria. RESULTS: There was no difference between 3D-CRT and IMRT in the incidence of GI and GU toxicity at 3 years. On multivariate analysis, transurethral resection of prostate/open transvesical prostatectomy (TURP/TVPE) for benign prostatic hyperplasia, carried out before radiotherapy, significantly increased the risk of Grade >or=2 GU toxicity (risk ratio 1.88). Among patients who experienced TURP/TVPE, the 5-year actuarial likelihood of Grade 2-3 urinary incontinence was 23%, compared with 9% for those without prostate surgery (P = 0.01). CONCLUSIONS: Tolerance of 3D-CRT and IMRT was similar, despite the use of high radiation dose with IMRT. Previous TURP/TVPE increased the risk of GU toxicity.

Audio-visual navigation reduces treatment time in deep-inspiration breath hold radiotherapy.

AIMS: The purpose of this study was to compare the treatment times for deep-inspiration breath hold with and without audio-visual (A-V) navigation. METHODS: We measured the real treatment time in 60 patients with breast cancer undergoing postoperative radiotherapy. Thirty consecutive patients were treated without deep-inspiration breath hold (DIBH) and another 30 patients using deep-inspiration breath hold (10 patients with DIBH only, 10 patients with DIBH using visual feedback and 10 patients with DIBH using visual feedback following breath training). The treatment time was relativized to number of fields and 100 monitor units (MU). The independent t-test was used to analyse differences between cohorts. RESULTS: The mean treatment time for patients without DIBH was 46.5 seconds per field and 90.9 seconds per 100 MU, for DIBH only 92.3 and 170.2 seconds, for DIBH with audio-visual navigation 68.1 and 133.8 seconds, and for DIBH with A-V feedback including breath training 66.1 and 132.5 seconds. The treatment times for patients treated using DIBH with visual navigation were significantly shorter in comparison with patients without visual feedback. We were not able to prove any significant benefit for breath training in terms of reducing the treatment time. CONCLUSION: Audio-visual navigation enables to significantly reduce the treatment time in comparison with DIBH without A-V feedback.

Therapeutic significance of hormone receptor positivity in patients with HER-2 positive breast cancer.

Breast cancer with high expression of human epidermal growth factor receptor (HER)-2 represents a biologically and clinically heterogeneous group of neoplastic disorders. Importantly, hormone receptor expression has an effect on biological properties and affects the selection of therapies. On the basis of molecular genetics, four principal subtypes, including luminal A, luminal B, HER2-enriched (HER-2-E), and basal-like can be distinguished. Breast tumors characterized by HER-2 positivity and simultaneous expression of hormone receptors, triple positive breast cancers (TPBC) are of increasing interest owing to the unique biological characteristics associated with complex interactions between HER-2 and hormone receptor signaling pathways. Interactions between hormone receptors and HER-2 explain the decreased efficacy of hormonal therapy in comparison with HER-2-negative patients. The expression of estrogen receptors in HER-2 positive tumors may also be associated with resistance to anti-HER-2 treatment. Multiple available therapeutic options, including hormonal therapy, anti-HER-2 agents and cytotoxic drugs explain favorable prognosis of TPBC. Escalation and de-escalation therapeutic strategies that could result in lower toxicities are being investigated as well as combinations of anti-HER-2 agents with hormonal therapy, immunotherapy, cyclin dependent kinase 4/6 and phosphatidyl inositol-3-kinase inhibitors. Distinction between subtypes of HER-2-positive breast cancer and treatment diversification may result in improved outcomes in TPBC. A response to neoadjuvant therapy may serve in the tailoring of therapy management.

Bisphosphonates for bone metastatic disease from breast cancer: clinical practice in the Czech Republic.

BACKGROUND: The use of bisphosphonates (BPs) represents a standard therapy of bone metastatic disease from breast cancer and has been incorporated in many systemic international guidelines. We have tried to evaluate the use of BPs in current clinical practice across the Czech Republic. PARTICIPANTS AND METHODS: A covering letter, questionnaires and pre-paid envelopes were mailed to the head oncologists of 64 workplaces of Czech Oncology Society. Total 310 questionnaires were sent out. The questionnaire consisted of 23 questions. RESULTS: The questionnaires were completed and returned by 91 oncologists from 32 workplaces. Most of the responding oncologists worked at university hospitals (42%), the most frequent length of work experience was 5 to 10 years (30%) and the most frequent rate of breast cancer patients was from 10 to 25% (45%). Ninety-five percent of the oncologists regularly initiated BP therapy, and oral clodronate was the first choice BP (77%). Once initiated, the treatment was discontinued in less than 5% patients (24%). Seventy-one (79%) oncologists stated that the most important reason leading to therapy termination was impairment of performance status. CONCLUSIONS: The consensual agreement pointed out that it could be a fundamental step towards establishing the national treatment guidelines for the BP use in metastatic breast cancer patients.

Tumor bed radiotherapy in women following breast conserving surgery for breast cancer-safety margin with/without image guidance.

Image guided radiation therapy (IGRT) enables the achievement of higher precision in radiation delivery, a reduction in safety margins and a reduced risk of toxicity in healthy tissues. The present study investigated the magnitude of safety margins for the radiation boost setup on skin marks or metal clips implanted into the tumor bed during breast cancer surgery. One hundred eighty-four patients after breast conserving surgery with implanted metal clips into tumor bed were analyzed. The present study investigated the difference in safety margin required for the treatment setup on skin marks and metal clips. The skin marks were created using a positioning laser system in the treatment room. Metal clips implanted in the tumor bed were registered using IGRT with kilovoltage X-rays in orthogonal projection. Treatment setup was performed during free breathing. The safety margin corresponding to the planning target volume (PTV) was calculated from the recorded data. Calculated safety margins for the treatment setup on skin marks were 9.4, 11.1 and 11.1 mm in the anteroposterior, craniocaudal, and laterolateral directions, respectively. Corresponding safety margins with the use of IGRT and metal clips registration were 4.7, 5.1 and 5.9 mm, respectively. The safe PTV margin was 12 mm using setup on skin marks without IGRT, whereas a 6-mm margin was sufficient with the use of metal clip-based IGRT with daily online correction. IGRT has been adopted as the standard treatment method within the Oncology Centre of Multiscan and Pardubice Hospital (Pardubice, Czech Republic).

Solitary extramedullary plasmacytoma in the oropharynx: advantages of intensity-modulated radiation therapy.

We report a case of a 59-year-old man with solitary extramedullary plasmacytoma in his oropharynx. Because the diagnosis is rare and there is only limited experience in the literature based on retrospective data, the optimal planning target volume and optimal dose of radiation therapy (RT) are still controversial. The frequently discussed problem is the necessity of first echelon lymph node irradiation because it is associated with a higher rate of complications such as xerostomia caused by damage to salivary glands. In order to prevent late toxicity, intensity-modulated RT with the use of simultaneous integrated boost and parotid salivary gland sparing was used in this patient's treatment. The RT was performed in 23 identical fractions, the primary tumor region was irradiated with a dose of 46 Gy and the first echelon lymph node region with the risk of subclinical disease with a dose of 41.4 Gy; the dose per fraction was 2 Gy and 1.8 Gy, respectively. The patient is alive and well > 20 months after the irradiation, without any evidence of disease. Parotid gland function remained intact, and no xerostomia occurred. This is the first report of the use of intensity-modulated RT with parotid gland sparing in the treatment of solitary extramedullary plasmacytoma in the head and neck region.

The technique of intensity-modulated radiotherapy in the treatment of cholangiocarcinoma.

AIMS AND BACKGROUND: Conventional radiotherapy in inoperable cholangiocarcinoma is limited by radiotolerance of the surrounding tissues. The aim of our dosimetric study was an evaluation of intensity-modulated radiotherapy in the treatment of inoperable bile duct carcinoma. METHODS: Four patients with inoperable cholangiocarcinoma treated by self-expandable stent placed to the biliary tree and radiotherapy were studied. The rotational technique, conformal 3D BOX technique and intensity-modulated radiotherapy plan were compared. Dose volume histograms and the normal tissue complication probability concept were used for comparison. The stent was used for target motion verification. RESULTS: The intensity-modulated radiotherapy plans showed favorable dose distribution in planning target volume and remarkable sparing of organs at risk. CONCLUSIONS: The intensity-modulated radiotherapy technique in bile duct carcinomas deserves further research and clinical evaluation.

IMRT with the use of simultaneous integrated boost in treatment of head and neck cancer: acute toxicity evaluation.

Acute toxicity has been evaluated in head and neck cancer patients treated with intensity-modulated radiotherapy using simultaneous integrated boost (SIB-IMRT). The basis of the treatment protocol is an irradiation in 30 fractions with a total dose: 66 Gy to the region of macroscopic tumor, 60 Gy to the region of high-risk subclinical disease and 54 Gy to the region of low-risk subclinical disease. Between December 2003 and September 2005, 38 patients with carcinoma of different locations in the head and neck region were irradiated. Five patients underwent concurrent chemotherapy (weekly cisplatin). Acute toxicity was evaluated according to Radiation Therapy Oncology Group toxicity scale for skin, mucous membrane, salivary glands, pharynx and esophagus and larynx. All 38 patients completed the therapy without urgency of interruption due to acute toxicity of radiotherapy. No patient experienced grade 4 toxicity. More severe toxicity was observed in patients with concurrent chemotherapy. The results confirm that the irradiation according to our SIB-IMRT protocol is a therapy with acceptable toxicity and there is a space for radiobiological enhancement of this regimen by concurrent chemotherapy, e.g. weekly cisplatin.

Is it reasonable to consider second-line chemotherapy in patients with hormone-refractory prostate cancer?

At present, no consensus exists regarding the use of second-line chemotherapy in patients with hormone-refractory prostate cancer (HRPC). A total of 23 patients with evidence of disease progression during or after first-line chemotherapy (epirubicin, etoposide, and dexamethasone) were included in this study. Two second-line treatments were administered throughout the study period (2000-2004) with 15/23 patients receiving carboplatin AUC 3 on day 1 and vinblastine 5 mg/m2 on day 1 of a 21-day cycle and 8/23 patients treated with docetaxel 50 mg/m2 on day 1 of a 21-day cycle. The latter regimen has been used since 2003. The prostate-specific antigen (PSA) level decreased by > or =50% in 3 of 23 patients, corresponding to an overall PSA response rate of 13% (95% confidence interval, 3-34%). The median time to biochemical progression was 9, 24 and 33 weeks, respectively. The median overall survival was 39 weeks (range, 15-73 weeks) with no difference between the two chemotherapy groups (p=0.08). A significant reduction of analgesic use was observed in 2 of 10 patients (20%) who required analgesics for cancer pain upon study entry. The major toxicity was grade 3 thrombocytopenia in 2 of 23 patients (9%). Both second-line treatments, a combination of carboplatin and vinblastine and a monotherapy with docetaxel, showed modest activity at subtoxic doses in patients with HRPC.

Perioperative hyperfractionated high-dose rate brachytherapy combined with external beam radiotherapy in the treatment of soft tissue sarcomas.

AIMS AND BACKGROUND: Low-dose rate brachytherapy alone or in combination with external beam radiotherapy represents a well-established adjuvant treatment in soft tissue sarcomas following surgical resection. The experience with high-dose radiotherapy in this indication is limited. The purpose of our study was an evaluation of the viability of perioperative hyperfractionated high-dose rate brachytherapy in combination with external beam radiotherapy for primary and recurrent soft tissue sarcomas. PATIENTS AND METHODS: From February 1998 through June 2002, 10 adult patients with soft tissue sarcomas were treated by interstitial perioperative high-dose rate brachytherapy and external beam radiotherapy. TNM classification was pT2bpN0pM0 in 9 patients and pT1bpN0pM0 in 1 patient. Grade of differentiation was G1 (2 patients), G2 (n = 1), G3 (n = 5), G4 (n = 2). Surgical margins were negative in 7 cases, close in 2 cases and positive in 1 case. The tumor was localized in an extremity in all cases. Hyperfractionation 3 Gy twice daily at 10 mm from the plane of sources was used for brachytherapy, with total doses 18-30 Gy. The patients received external beam radiotherapy with doses 40-50 Gy after brachytherapy. Follow-up periods were between 24-71 months (median, 46). RESULTS: Local control of the disease was achieved in all 10 patients. Distant metastases occurred in 2 cases. One patient was disease free after salvage surgery and chemotherapy, and one patient died of lung disease progression 14 months after brachytherapy. In one case, subcutaneous fistula occurred after radiotherapy and was cured by an excision. Six patients experienced grade 1 or 2 fibrosis and 1 case a mild peripheral neuropathy was recorded. CONCLUSIONS: Our study on a small number of patients suggests that perioperative hyperfractionated high-dose rate brachytherapy with doses 8 x 3 Gy in combination with external beam radiotherapy 40-50 Gy is a promising method to achieve high biological doses in the postoperative radiotherapy of soft tissue sarcomas without severe late morbidity and warrants further research.

Comparison of rectal dose-volume constraints for IMRT prostate treatment planning.

The purpose of this paper is to compare different sets of rectal dose-volume constraints and to develop input criteria for the intensity-modulated radiation therapy (IMRT) of prostate cancer. The IMRI treatment plans were created using Varian planning system (CadPlan with Helios module) for ten patients with localized prostate cancer (isocenter dose 78 Gy). The posterior portion of rectum was contoured as an extra volume (help volume). Three sets of input parameters for rectum with gradually increasing priorities (25-50-75-90) were designed for the inverse treatment planning: 1. dose-volume constraints allowing no more than 50, 40, 20 and 10% of the rectum volume be irradiated to 50, 60, 70, and 75 Gy, respectively-volume-based plans, priorities 25-90 (V25-90 plans); 2. maximum dose constraint of 74.1 Gy for rectum-plans with limited maximum reactal dose, priorities 25-90 (M25-90 plans); 3. maximum dose constraint of 50 Gy for the help volume-plans with limited maximum dose for the help volume, priorities 25-90 (H25-90 plans). Dose homogeneity in the planning target volume (PTV) and the rectal volumes (RV) irradiated to 50, 60, 70, and 75 Gy (RV 50-75 Gy) were recorded. Rectum sparing improved for all the plans with increasing priority. While the M plans had the lowest RV 75 Gy values, the H plans gave the minimum RV 50-70 Gy values. Plans were considered acceptable if at least 98% of the PTV was treated to 95% of the prescribed dose. In particular plan groups, the V75, M75, and H50 plans, together with the V50+M75 and H50+M75 combined plans, satisfied this condition and yielded the lowest rectal doses. The H50+M75 combined plan allowed optimal sparing of rectum (RV 50 Gy 51.6%, RV 60 Gy 38.5%, RV 70 Gy 26.0%, and RV 75 Gy 9.1%, respectively). An optima set of dose-based rectal constraints (maximum rectal dose 74.1 Gy, maximum help volume dose 50 Gy) has been developed for Varian planning software. These parameters will constitute a starting point for the prostate IMRT plan optimization.

Metastatic carcinoma of breast or a chordoma? A case report and clinical perspectives.

We present a case of chordoma in a patient who had been previously treated for ductal carcinoma of the breast. The initial clinical findings and radiological studies suggested a possibility of metastases. However, the findings also adhered to the classical presentations and findings of the chordoma of the base of skull. It was only after the surgical resection and immunohistochemical confirmation that the diagnosis of chordoma could be established. Here, we discuss chordoma with the analysis of our clinical intrigue.

[Intensity-modulated radiotherapy in the treatment of thyroid cancer]. / Radioterapie s modulovanou intenzitou v lécbe karcinomu stítné zlázy.

The main problem of the conventional radiotherapy in postoperative or curative irradiation in thyroid cancer is to achieve a sufficient dose in the planning target volume with acceptable dose distribution homogeneity and at the same time not to exceed tolerance doses in the organs of risk. Our study presents the advantages of intensity-modulated radiotherapy over conventional radiotherapy on an example of dosimetric comparisons of isodose plans of three patients treated at our department. The intensity-modulated radiotherapy in thyroid cancer offers an improvement of dose homogeneity and better sparing of organs at risk (spinal cord and lungs). Furthermore, dose escalation is feasible in the whole initial planning target volume up to 60 Gy with a simultaneous sparing of healthy tissues and organs at risk.

Searching for an appropriate image-guided radiotherapy method in prostate cancer--implications for safety margin.

AIMS AND BACKGROUND: The aim of the study was to compare the safety margin width using skin marks, pelvic skeleton-based targeting and adaptive protocol combining cone-beam computed tomography and kilovoltage image matching. METHODS: A total of 434 consecutive patients were treated by image-guided radiotherapy from November 2008 to April 2012. An adaptive protocol combining cone-beam computed tomography and kilovoltage image matching with individualized safety margin calculation according to the Van Herk method was used in a total of 201 patients. The remaining 233 patients had their setup corrected using cone-beam computed tomography daily. RESULTS: Analysis of the 3,137 cone-beam computed tomography images (201 patients) revealed that the margins between the clinical target volume and planning target volume with skin marks registration should be 1.24 cm in the anteroposterior, 0.98 cm in the craniocaudal, and 1.03 cm in the laterolateral direction. Considering pelvic skeleton-based setup, values of the clinical target volume and planning target volume margins in the anteroposterior, craniocaudal and laterolateral axis were 0.79 cm, 0.41 cm, and 0.19 cm, respectively. In a group of 8,872 cone-beam computed tomography images (233 patients) using CBCT assessment, the calculated margins between clinical target volume and planning target volume with skin marks were 1.15 cm in anteroposterior, 1.06 in craniocaudal, and 1.19 in laterolateral directions. Considering the pelvic skeleton-based setup, the corresponding values were 0.74 cm, 0.51 cm, and 0.25 cm. With the adaptive technique, the margins of most patients in the anteroposterior, craniocaudal, and laterolateral axes were 6 mm, 6 mm, and 6 mm or 8 mm, 6 mm, and 6 mm, respectively. CONCLUSIONS: The adaptive protocol combining cone-beam computed tomography and kilovoltage image matching or daily cone-beam computed tomography allowed us to substantially reduce the safety margins compared with skin marks targeting.