Local and systemic treatment for HER2-positive breast cancer with brain metastases: a comprehensive review.

The management of human epidermal growth factor receptor (HER2)-positive breast cancer has improved over the past decade. However, despite improvements in systemic control, a substantial proportion of patients with advanced HER2-positive breast cancer suffer from central nervous system metastases and even intracranial progression after aggressive local treatment. There is paucity of data and no consensus on the systemic therapies for patients with intracranial progression. This review discusses both local and systemic treatments for HER2-positive breast cancer with brain metastases with a special focus on the response of central nervous system metastases. A recommended practical treatment algorithm to guide physicians in selecting the most appropriate anti-HER2 therapy for their patients is suggested.

A statistics-based model for prediction of achievability of the planning criteria for IMRT planning.

The purpose of this study is to develop and evaluate a statistics-based model to predict the achievability of the planning criteria for intensity-modulated radiation therapy planning. A statistics-based model was proposed to predict the achievability of the planning criteria based on the structure set. A retrospective study was performed to validate the proposed model. A total of 160 prostate cases and 134 nasopharynx (NP) cases were used as the training set to build the model while 200 cases for each treatment site were used to validate the proposed model. An overlapping ratio and the minimum distance between organ at risks (OARs) and planning target volumes were used to predict the achievability of the planning criteria for serial organs. Since both prostate and NP cases were treated with simultaneous boost using multiple targets with different prescription doses, the effect of each parameter on the OARs was studied by binary logistic regression. For parallel organs, average distance to dose level was introduced and it described the dose falloff gradient within each OAR. By studying the distribution of average distance to dose level in the training set for each OAR, the result was used to predict the dose volume and average dose criteria. The accuracy of the proposed model was evaluated by comparing the predicted proportion and the actual proportion of the validation group that can achieve the clinical planning criteria. For prostate cases, the differences between the actual and predicted proportions were small for all criteria of rectum and bladder. The maximum deviations were 7% for bladder, 9% for rectum, and 5% for femur. For NP cases, the difference ranged from 0% to 7% with the largest difference found at the criterion D50% < 30 Gy of the parotids. In conclusion, the proposed statistics based plan prediction model was presented and the results showed the model could achieve acceptable prediction accuracy. The proposed tools could be used to calculate the probability of the OARs to achieve the clinical goals. This statistics based model can be further developed to adapt into the planning objective estimation in the auto-planning process.

Third-line systemic treatment in advanced/metastatic gastric cancer: a comprehensive review.

The management of advanced gastric cancer has improved over the past decade. There is more evidence to support the efficacy of systemic treatment in refractory gastric cancer beyond second-line treatment. Important randomized controlled trials of chemotherapies, targeted agents and immunotherapies have been reported. With the development of these novel therapies, clinicians can better individualize treatment for patients beyond progression on second-line therapy. However, there is no guideline on third-line therapy available for clinicians. This review discussed the efficacy and safety data from the pivotal trials of the agents proven to be effective in third-line settings, including the quality of study design, level of evidence and subgroup analysis, and how the data can help to guide clinicians on selecting the most appropriate third-line therapy for their patients.

Report of a study on IMRT planning strategies for ethmoid sinus cancer.

AIM: This communication reviews the planning strategies and dose statistics of nine IMRT plans generated for a complex head and neck case. PATIENT AND METHOD: An ethmoid sinus cancer case was sent as an IMRT planning task to all participants of the ESTRO course on "IMRT and Other Conformal Techniques in Practice", held in Amsterdam in June 2001. RESULTS: Nine IMRT plans were generated for the case, the majority of the plans generated with commercial planning systems. The number of beam incidences ranged between four and eleven, while five of the nine beam setups were coplanar. The planning target volume dose homogeneity was inversely correlated with the degree of sparing of the surrounding organs at risk. CONCLUSION: IMRT strategies for complex head and neck cases, such as ethmoid sinus cancer, can be strikingly different in various aspects, such as beam setup, total number of segments, PTV dose coverage and dose statistics for organs at risks.