In this article, our goal is to compare the TMR10 and convolution dose calculation algorithm in GammaPlan used in stereotactic radiosurgery (SRS) treatments with Gamma Knife and to assess if the algorithms produce clinically significant differences.

Treatment plans were analysed from ten patients who have undergone Gamma Knife SRS treatments. Patient plans were retrospectively recalculated using Lesksell GammaPlan 10 treatment software utilising the TMR10 and convolution dose calculation algorithms in order to create a paired dataset for comparison. Evaluation was based on the dose volume histogram (parameters of minimum, mean, maximum and integral doses.

The ratios of average integral doses calculated by the convolution dose calculation algorithm to the average integral doses calculated by the TMR10 algorithm are 0·997 for the target (p=0·028), 1·048 (p=0·48) for the skull and 1·005 (p=0·68) for the brainstem.

Although doses calculated with the convolution algorithm resulted in slightly higher mean integral doses for the brainstem and skull critical structures when compared to that of TMR10 doses, these results were not statistically or clinically significant. Thus we continue to use the TMR10 algorithm at our clinic.

The unique behaviour of microbubbles under ultrasound acoustic pressure makes them useful agents for drug and gene delivery. Several studies have demonstrated the potential application of microbubbles as a non-invasive, safe and effective technique for targeted delivery of drugs and genes. The drugs can be incorporated into the microbubbles in several different approaches and then carried to the site of interest where it can be released by destruction of the microbubbles using ultrasound to achieve the required therapeutic effect.

The objective of this article is to report on a review of the recent advances of ultrasound-mediated microbubbles as a vehicle for delivering drugs and genes and its potential application for the treatment of cancer.

Ultrasound-mediated microbubble technology has the potential to significantly improve chemotherapy drug delivery to treatment sites with minimal side effects. Moreover, the technology can induce temporary and reversible changes in the permeability of cells and vessels, thereby allowing for drug delivery in a spatially localised region which can improve the efficiency of drugs with poor bioavailability due to their poor absorption, rapid metabolism and rapid systemic elimination.

Volumetric modulated arc therapy (VMAT), an extension of intensity modulated radiation therapy (IMRT), employs modifications in gantry rotation speed, machine dose rate and multi-leaf collimator motion to deliver a three-dimensional dose distribution. This study compared VMAT to IMRT for patients with anal carcinoma.

Sixteen patients previously treated with IMRT were retrospectively selected. Each patient received a total dose of 57·6–63·0 Gy in 1·8 Gy fractions. A single- or double-isocenter multi-arc VMAT treatment plan was generated using Eclipse RapidArc system with the same computed tomography image sets and optimisation constraints used for IMRT. Dose–volume histograms (DVHs) for planning target volumes (PTVs) and organs at risk (OARs), and monitor units (MUs) and beam on times (BOTs) were used for comparison.

IMRT and VMAT plans showed insignificant differences in PTV homogeneity and conformity and sparing hips and bowel. VMAT required fewer mean MU and shorter BOT per plan (1,597 MU, 2·66 min) compared to IMRT (2,571 MU, 4·29 min) with p < 0·0001.

Fewer MU and shorter BOT for VMAT may decrease the damage from secondary radiation and treatment delivery uncertainty due to intra-fraction tumour motion, leading to higher machine throughput and improving patient comfort, with less treatment time.

Multiform glioblastoma (MG) represents 70% of all gliomas, with half of patients older than 65 years with median survival of 12–18 months, hypofractionation seeks to reduce the intensity and duration of treatment without impacting on survival rates. The objective was to determine the global survival and recurrence-free survival of adults over 70 years old with MG treated with hypofractionated radiotherapy and standard scheme. The review of patients older than 70 years treated with radiotherapy from 2013 to 2016 was performed.

Twenty-four patients were analysed, with a median follow-up of 239 days, and there is no difference in overall survival 12·3 versus 10·5 months (p = 0·55) and recurrence-free survival 8·3 versus 3·4 months (p = 0·48) between both schemes, conventional versus hypofractioanted, respectively.

The results in this study show that hypofractionated scheme could be comparable in overall survival and recurrence-free survival to conventional fractionation, but a longer patients’ trial should be done.

Accurate localisation of target position is crucial when using techniques with sharp dose fall off such as volumetric modulated arc therapy (VMAT). Gold seed fiducial markers have been used for target localisation in image-guided radiation therapy for various tumors including intact prostate cancers. However, their role for target localisation in post-prostatectomy radiotherapy is unclear. This study was undertaken to determine the feasibility and effectiveness of gold seed fiducial markers in patients undergoing prostate bed VMAT.

The institutional radiation oncology database was used to analyse the treatment data of 18 post-prostatectomy patients with implanted gold seed fiducial markers. The shifts of the fiducial markers were reviewed, tabulated and statistically analysed.

Three hundred and eighty-six orthogonal pair images for 18 patients were reviewed. Specifically, the average gold seed fiducial shifts were 0·34 cm in the superior–inferior (S/I) axis (0·31 SD), 0·31 cm (0·29 SD) in the anterior–posterior (A/P) axis and 0·28 cm (0·25 SD) in the lateral axis (R/L). As a result, the 95% probability of fiducial marker displacement was 0·96 cm in the S/I, 0·89 cm in the A/P and 0·78 cm in the R/L axes. The most frequent shifts occurred in the inferior, left and posterior directions. The percentage of shifts more than 0·5 cm were 19·74, 21·56 and 12·47% for the S/I, A/P and R/L axes, respectively.

In the absence of fiducial markers, non-uniform planning target volume (PTV) margins of 1 cm for S/I, 9 mm for A/P and 8 mm for the lateral direction are necessary for target localisation in post-prostatectomy radiotherapy. By improving prostate bed localisation, gold seed fiducial markers can decrease PTV margins, reduce normal tissue radiation exposure and allow for dose-escalated and/or hypofractionated radiotherapy to be considered in appropriate clinical scenarios.

Breast cancer is the most common cancer among females worldwide. Increasing breast cancer incidence rates, improved diagnosis and management modalities and growing life expectancy have resulted in increasing numbers of women at risk of developing contralateral primary breast cancer. Bilateral breast cancer can occur synchronously or metachronously.

This study reports three cases of bilateral breast cancer patients treated at our oncology department between March 2018 and March 2019. The features of presentation, investigation, diagnosis and follow-up care are the highlights of this study.

Bilateral breast cancer was noted in three patients among the study population in the age group of 35 –55 years. Two of these patients had metachronous bilateral breast cancer, and one patient developed cancer in the second breast during the course of management. The second breast cancers differed histologically from primary breast cancer.

Poor awareness on breast cancer care and the lack of national screening guidelines and programmes, and poor infrastructure, all contribute to late presentation and difficult breast cancer management. Proper history, clinical examination and imaging of opposite breast should be done to ensure adequate and timely management of bilateral breast cancer.

Cancer during pregnancy has an incidence of 1/1,000, and when diagnosed, the most common ones are breast cancer (1/10,000), Hodgkin’s lymphoma (1/6,000), and head and neck cancer (1/10,000). If a diagnosis is made during pregnancy, the treatment cannot wait until delivery, and there is concern about the effects that radiotherapy may have on the foetus. The multidisciplinary group has to assess and ethically make decisions with regard to the mother and foetus.

A 35-year-old female, a carrier of Behcet’s disease, underwent 5 years of treatment with hydroxychloroquine, prednisone and low-molecular-weight heparin (the patient being a carrier of Behcet’s disease, there is a high risk for cancer of the oral cavity and oropharynx with an HR of 2·11, so the cancer could be related to the tonsil). The patient’s oncological situation started on December 2017 with a volume increase in preauricular, parotid and right mandibular angle, with a progressive growth. At this time, the foetus was of 17·5 weeks of gestation. An oral cavity tumour that invaded the right retromolar triangle was observed, and upon biopsy, a basaloid squamous cell carcinoma was diagnosed.

Radiotherapy treatment was started at 22 weeks of gestation; intensity-modulated radiation therapy (IMRT) was planned with a dose of 69·96 Gy to the primary tumour and 59·4 Gy to ganglion levels II, III and IV, bilaterally in 33 fractions. At fraction 27 a significant decrease in tumour volume was noted, so adaptive radiotherapy was performed to complete the treatment. Currently the patient has no clinical evidence of tumour pathology.

The risk of radiation exposure in pregnant women (after 20 weeks of gestation), being treated for cancers of the tonsil, reaching the foetus is minimal, with a reduced risk of a few or no effects.

Radiotherapy in tonsil cancer has been shown to be effective in combination with chemotherapy for local control of the disease. In the case of this pregnant patient, radiotherapy, as the only modality, provided local control and little exposure of radiation to the foetus.