Assessment of contralateral mammary gland dose in the treatment of breast cancer using accelerated hypofractionated radiotherapy

AIM:To measure the dose distribution,related to the treatment planning calculations,in the contralateral mammary gland of breast cancer patients treated with accelerated hypofractionated 3-dimensional conformal radiotherapy.METHODS:Thirty-four prospectively selected female patients with right breast cancer (pN0,negative surgical margins) were treated with breast-conserving surgery.A total dose of 42.5 Gy (2.66 Gy/fraction) was prescribed;it was requested that planning target volumes be covered by the 95% isodose line.The contralateral mam-mary gland was defined on CT simulation.The dose received was evaluated by dose volume histograms.RESULTS:The measured contralateral breast doses were:(1) Dose maximum:290-448 cGy [Equivalent (Eq) 337-522 cGy];(2) Mean dose:45-70 cGy (Eq 524815 cGy);and (3) Median dose:29-47 cGy (337-547 cGy) for total primary breast dose of 42.5 Gy in 16 equal fractions.The spearman rho correlation showed statistical significance between the contralateral breast volume and maximum dose (P=0.0292),as well as mean dose (P=0.0025) and median dose (P=0.046) to the breast.CONCLUSION:Minimizing the dose to the contralateral breast has to be one of the priorities of the radiation oncologist when using short schedules because of the radiosensitivity of this organ at risk.Further study is necessary to assess the long-term clinical impact of this schedule.     

Role of radiotherapy in the management of hepatocellular carcinoma:A systematic review

Many patients with hepatocellular carcinoma(HCC) present with advanced disease,not amenable to curative therapies such as surgery,transplantation or radiofrequency ablation. Treatment options for this group of patients include transarterial chemoembolization(TACE) and radiation therapy. Especially TACE,delivering a highly concentrated dose of chemotherapy to tumor cells while minimizing systemic toxicity of chemotherapy,has given favorable results on local control and survival. Radiotherapy,as a therapeutic modality of internal radiation therapy with radioisotopes,has also achieved efficacious tumor control in advanced disease. On the contrary,the role of external beam radiotherapy for HCC has been limited in the past,due to the low tolerance of surrounding normal liver parenchyma. However,technological innovations in the field of radiotherapy treatment planning and delivery,have provided the means of delivering radical doses to the tumor,while sparing normal tissues. Advanced and highly conformal radiotherapy approaches such as stereotactic body radiotherapy and proton therapy,evaluated for efficacy and safety for HCC,report encouraging results. In this review,we present the role of radiotherapy in hepatocellular carcinoma patients not suitable for radical treatment.     

Stereotactic radiosurgery and radiotherapy for acoustic neuromas

Neuromas are benign intracranial tumors with indolent natural history. Surgery is the mainstay of treatment and only after the introduction of single-fraction stereotactic radiosurgery (SRS), radiotherapy emerged as an alternative viable option. In this review, we focused on SRS or conventionally fractionated stereotactic radiotherapeutic (FSRT) approaches. We described the results of different doses used for SRS and FSRT, the current status, and a comparison between the two radiotherapy approaches. Stereotactic radiotherapy techniques aim to control tumor growth with minimal toxicity. SRS using either a cobalt unit or a linear accelerator has given high rates of tumor control and of cranial nerve function preservation with marginal doses range of 12–14 Gy. Fractionated stereotactic radiotherapy (FSRT) is optimal for tumors larger than 3 cm. Doses as low as 50.4 Gy provide excellent control rates and low morbidity. Overall, both SRS and FSRT are equally effective and safe options for neuroma patients who do not need immediate surgical decompression.