Radiotherapy for large cutaneous angiosarcoma of face with RapidArc (VMAT)

Angiosarcoma is a rare malignancy of vascular origin. It can affect any part of the body, head and neck region being probably the most common site of diagnosis. We present here a case of Angiosarcoma of face in a 67-year-old elderly gentleman who was treated with RapidArc – volumetric modulated arc therapy (VMAT) for recurrence after surgery, radiotherapy and chemotherapy. As an alternative to Electron Beam Therapy, RapidArc with skin bolus can be considered for large complex shaped targets with irregular surface and tissue inhomogeneity. RapidArc plan can achieve adequate target coverage with acceptable dose homogeneity and conformity

Study of inter-fraction movements of tongue during radiation therapy in cases of tongue malignancy using volumetric cone beam computed tomography (CBCT) imaging

Purpose: Tongue is a mobile organ in head and neck region predisposing it for geographic miss during the course of fractionated radiotherapy for tongue malignancy. This study analyses movement of tongue during the course of radiotherapy using volumetric KV-cone beam computed tomography (KV-CBCT) imaging for patients of tongue malignancy treated without using tongue bite. Methods: We analysed 100 KV-cone beam CTs performed on 10 patients with carcinoma of tongue undergoing fractionated radiotherapy. All the patients underwent thermoplastic mask immobilisation and CT simulation. During the course of radiotherapy, all patients underwent volumetric KV-CBCT imaging to assess the movements of tongue. Five arbitrary reference points were used to analyse the movements of tongue in 3-dimensions: 1) Point A: Tip of tongue; 2) Point B: Point over right lateral border, 4 cm posterior to the tip of tongue; 3) Point C: Point over left lateral border, 4 cm posterior to the tip of tongue; 4) Point D: Point over superior most part (dorsum) of tongue, 4 cm posterior to the tip of tongue; 5) Point E: Point over the surface of base of tongue at the level of tip of epiglottis. Results: Mean movements of point A: +0.21 cm (SD: 0.12) and -0.23 cm (SD: 0.14), point B: +0.14 cm (SD: 0.04) and -0.19 cm (SD: 0.1), point C: +0.12 cm (SD: 0.05) and -0.14 cm (SD: 0.06), point D: +0.15 cm (SD: 0.07) and -0.29 cm (SD: 0.22) and point E: +0.23 cm (SD: 0.15) and -0.23 cm (SD: 0.14). Conclusion: Organ movement is one of the great challenges encountered during radiotherapy. Tongue is one such organ in head and neck region. Concept of internal target volume (ITV) margin which takes into account the internal organ movements should be considered for tongue malignancies. ITV to PTV margin will depend on the setup accuracy, immobilization device and imaging modality utilised for setup verification. In an IGRT (Image Guided Radio Therapy) setup, a PTV margin of 0.3 to 0.5 cm from ITV would be safe

Estimation of linear quadratic (LQ) model parameter alpha/beta (α/β) and biologically effective dose (BED) for acute normal tissue reactions in head and neck malignancies

Purpose: Linear-Quadratic (LQ) model has been widely used for describing radiobiological effectiveness of various fractionation schedules on tumour as well as normal tissues. This study estimates α/β for acute normal tissue reactions using Fe-plot method.Methods: 50 cases of locally advanced head and neck squamous cell carcinoma (stage III and IV) treated with external beam radiotherapy were included in this study. Patients were randomly distributed into Hyper-fractionation (HF) arm (1.2 Gy/fraction, twice daily, 6 hours apart) and conventional fractionation (CF) arm (2 Gy/fraction, once daily) with 25 cases in each arm. α/β and BED were calculated for acute normal tissue reactions using Fe-plot method.Results: In our study, the estimated values of α/β for RTOG (Radiation Therapy Oncology Group) grade 1, 2 and 3 skin reactions were 11.2 Gy, 10.1 Gy and 9 Gy respectively. Estimated values of α/β for RTOG grade 1, 2 and 3 mucosal reactions were 9.7 Gy, 8.0 Gy and 9.1 Gy respectively. For Hyper-fractionation arm, calculated BED values for grade 1, 2 and 3 skin reactions were 54.45 Gy11.239, 66.90 Gy10.114 and 73.43Gy9.001 respectively and for grade 1, 2 and 3 mucosal reactions were 33.5 Gy9.797, 57.8 Gy8.011 and 70.8 Gy9.106 respectively. For conventional fractionation arm, calculated BED values for grade 1, 2 and 3 skin reactions were 54.09 Gy11.239, 66.88 Gy10.114 and 73.33 Gy9.001 respectively and for grade 1, 2 and 3 mucosal reactions were 33.52 Gy9.797, 57.68 Gy8.011 and 70.73 Gy9.106 respectively.Conclusion: LQ model and the concept of BED provide an excellent tool to compare different fractionation schedules in radiotherapy. The estimated values of α/β for acute reacting normal tissues are in good agreement with the available literature

Is there seasonal variation in symptom severity, uroflowmetry and frequency-volume chart parameters in men with lower urinary tract symptoms?

Purpose: There is a widely held perception that lower urinary tract symptoms may be exacerbated by cold weather. In this study, we examine the effect of seasonal variation in ambient temperatures on frequency–volume chart derivatives, symptom severity scores and uroflowmetry parameters in men with lower urinary tract symptom.<p></p> Methods: Between January 2000 and April 2004, men presenting with lower urinary tract symptom were prospectively recruited and assessed in Edinburgh, UK (55°52′N) with maritime temperate climates (Köppen classification Cfb). Local monthly temperatures were extracted from national meteorological records. Patients completed the International Prostate Symptom Score and 3-day frequency volume chart before undergoing free uroflowmetry with post-micturition volume measurement. Exclusion criteria were previous bladder outflow surgery and anti-cholinergic medication.<p></p> Results: Data on 296 patients were suitable for analysis. Mean age was 62.3 years (range, 26–90). Over the period of study, the coldest month was January (mean = 4.7℃) and the warmest month was August (mean = 15.8℃). There was no significant variation in either International Prostate Symptom Score symptom scores by season (p > 0.05) or any frequency–volume chart parameters, with the exception on an increase in median actual nightly voids over the summer months (p = 0.021). There was no significant correlation between maximal flow rate and post-micturition residual volumes and mean monthly temperatures (p > 0.05).<p></p> Conclusions: Seasonal variation in nocturia, but not other frequency–volume parameters, symptom severity or uroflowmetry parameters, is significant in men with lower urinary tract symptom. Future work should consider the impact of seasonal variation in lower urinary tract symptoms in both sexes across a wider range of climates

Radiotherapy for large cutaneous angiosarcoma of face with RapidArc (VMAT)

Angiosarcoma is a rare malignancy of vascular origin. It can affect any part of the body, head and neck region being probably the most common site of diagnosis. We present here a case of Angiosarcoma of face in a 67-year-old elderly gentleman who was treated with RapidArc – volumetric modulated arc therapy (VMAT) for recurrence after surgery, radiotherapy and chemotherapy. As an alternative to Electron Beam Therapy, RapidArc with skin bolus can be considered for large complex shaped targets with irregular surface and tissue inhomogeneity. RapidArc plan can achieve adequate target coverage with acceptable dose homogeneity and conformity.</p

Study of inter-fraction movements of tongue during radiation therapy in cases of tongue malignancy using volumetric cone beam computed tomography (CBCT) imaging

Purpose: Tongue is a mobile organ in head and neck region predisposing it for geographic miss during the course of fractionated radiotherapy for tongue malignancy. This study analyses movement of tongue during the course of radiotherapy using volumetric KV-cone beam computed tomography (KV-CBCT) imaging for patients of tongue malignancy treated without using tongue bite. Methods: We analysed 100 KV-cone beam CTs performed on 10 patients with carcinoma of tongue undergoing fractionated radiotherapy. All the patients underwent thermoplastic mask immobilisation and CT simulation. During the course of radiotherapy, all patients underwent volumetric KV-CBCT imaging to assess the movements of tongue. Five arbitrary reference points were used to analyse the movements of tongue in 3-dimensions: 1) Point A: Tip of tongue; 2) Point B: Point over right lateral border, 4 cm posterior to the tip of tongue; 3) Point C: Point over left lateral border, 4 cm posterior to the tip of tongue; 4) Point D: Point over superior most part (dorsum) of tongue, 4 cm posterior to the tip of tongue; 5) Point E: Point over the surface of base of tongue at the level of tip of epiglottis. Results: Mean movements of point A: +0.21 cm (SD: 0.12) and -0.23 cm (SD: 0.14), point B: +0.14 cm (SD: 0.04) and -0.19 cm (SD: 0.1), point C: +0.12 cm (SD: 0.05) and -0.14 cm (SD: 0.06), point D: +0.15 cm (SD: 0.07) and -0.29 cm (SD: 0.22) and point E: +0.23 cm (SD: 0.15) and -0.23 cm (SD: 0.14). Conclusion: Organ movement is one of the great challenges encountered during radiotherapy. Tongue is one such organ in head and neck region. Concept of internal target volume (ITV) margin which takes into account the internal organ movements should be considered for tongue malignancies. ITV to PTV margin will depend on the setup accuracy, immobilization device and imaging modality utilised for setup verification. In an IGRT (Image Guided Radio Therapy) setup, a PTV margin of 0.3 to 0.5 cm from ITV would be safe.</p