Cancer treatment reviews
-
Cancer treatment reviews · Jun 2006
ReviewInactivation of O6-alkylguanine DNA alkyltransferase as a means to enhance chemotherapy.
DNA adducts at the O6-position of guanine are a result of the carcinogenic, mutagenic and cytotoxic actions of methylating and chloroethylating agents. The presence of the DNA repair protein O6-alkylguanine-DNA alkyltransferase (AGT) renders cells resistant to the biological effects induced by agents that attack at this position. O6-Benzylguanine (O6-BG) is a low molecular weight substrate of AGT and therefore, results in sensitizing cells and tumors to alkylating agent-induced cytotoxicity and antitumor activity. ⋯ O6-BG has also been found to enhance the cytotoxicity of agents that do not form adducts at the O6-position of DNA, including platinating agents. O6-BG's mechanism of action with these agents is not fully understood; however, it is independent of AGT activity or AGT inactivation. A better understanding of the effects of this agent will contribute to its clinical usefulness and the design of better analogs to further improve cancer chemotherapy.
-
Cancer treatment reviews · Jun 2006
Review Meta AnalysisOpioid switching: a systematic and critical review.
Cancer patients with pain may not respond to increasing doses of opioids because they develop adverse effects before achieving an acceptable analgesia, or the analgesic response is poor, despite a rapid dose escalation. Opioid switching may significantly improve the balance between analgesia and adverse effects. We conducted a systematic review of existing literature on opioid switching. ⋯ Reasons for switching may influence the dose of the alternative drug. Opioid conversion should not be a mere mathematical calculation, but just a part of a more comprehensive evaluation of pain, adverse effect intensity, comorbidities, and concomitant drugs. The process of reaching an optimal dose should be highly individualized, particularly when patients are switched from high doses of opioids, given the wide conversion ratios reported in literature.
-
Cancer treatment reviews · May 2006
Review Meta Analysis Comparative StudyEffectiveness of stereotactic radiosurgery alone or in combination with whole brain radiotherapy compared to conventional surgery and/or whole brain radiotherapy for the treatment of one or more brain metastases: a systematic review and meta-analysis.
To assess the effectiveness of SRS alone or in combination with WBRT compared to surgery and/or WBRT in prolonging survival and improving the quality-of-life and functional status of patients with brain metastases. ⋯ Adding SRS to WBRT improves survival in patients with one brain metastasis. Combining SRS and WBRT improves local tumour control and functional independence in all patients.
-
Cancer treatment reviews · Apr 2006
ReviewRadiation therapy and combined modality treatment of gastrointestinal carcinomas.
Ionizing radiation (IR) is a potent agent in enhancing tumor control of locally advanced cancer and has been shown to improve disease-free and overall survival in several entities. However, the role of radiotherapy (RT) in the treatment of gastrointestinal tumors remains controversial because of the marked radiation sensitivity of neighboring organs frequently compromising application of high doses of ionizing radiation. ⋯ Pre-operative RT or pre-operative chemo-radiation may be considered in individual cases, but should not be used routinely for gastro-intestinal carcinoma, except for rectal carcinoma. In many studies, pre-operative radiotherapy/chemo-radiation yielded promising results and merits validation in large controlled trials.
-
Cancer treatment reviews · Apr 2006
Randomized Controlled Trial Multicenter StudyTrastuzumab after primary treatment for early stage HER2-positive breast cancer reduces recurrence.