Treatment Survival Time Research Articles

The Use of Chemotherapy to Prolong the Life of Dogs Suffering from Cancer: The Ethical Dilemma.

Simple SummaryCancer is common in dogs and chemotherapy has advanced significantly in recent years with Veterinary oncology becoming a specialty in many countries such as the UK, Australia and the USA. However there have been no large-scale studies of the potential side effects of chemotherapeutic drugs in companion animals and very little discussion on the ethics of using chemotherapy in these animals. The prognosis for animals suffering from malignant neoplasia (that may be amenable to chemotherapy) generally remains poor and the place of oncology in veterinary medicine can be questioned. Employing the most relevant ethical theories regarding the nature of our duties to animals, the Animal Rights View, the Utilitarian View and the Relational (Contextual) view, this paper examines the ethics of using chemotherapy in dogs with cancer.Despite the emergence some years ago of oncology as a veterinary specialty, there has been very little in the way of ethical debate on the use of chemotherapy in dogs. The purpose of this article is to undertake an ethical analysis to critically examine the use of chemotherapy to prolong the life of dogs suffering from cancer. If dogs have no concept of the future and are likely to suffer at least some adverse effects with such treatments, consideration should be given as to whether it is ethical and in the animal’s best interests to use chemotherapy. Chemotherapeutic drugs are mutagenic, carcinogenic, teratogenic and may be irritant. Furthermore, chemotherapy may involve multiple trips to the veterinarian, multiple procedures and periods in isolation. Cancer-associated pain has been shown to be under-diagnosed and pet owners overestimate the effects of chemotherapy on treatment survival time. Of additional concern is the public health risks associated with chemotherapeutic drugs. As chemotherapy is not generally considered curative, it is in effect palliative care. However, palliative care may not be in the best interests of a terminally ill animal. As the specialty of veterinary oncology continues to grow and as the use of chemotherapy becomes more commonplace in the treatment of animals with cancer, it is imperative that there is an ongoing ethical debate on the use of chemotherapy in animals.

AB0387 Optimizing Treatment of Rheumatic Diseases with Biologic Agents in Our Day Hospital

BackgroundSince the development of biological therapy (BT), the patients refractory to other therapy responds favorably and a number of them with a state of remission or very low activity. These...

Saddlepoint approximations for rank‐invariant permutation tests and confidence intervals with interval‐censoring

AbstractInterval‐censored data occur when subjects are assessed by using regular follow‐up. In such instances, we consider rank‐invariant permutation tests to test the significance of a treatment versus a control. For a wide class of such tests, which includes the Peto & Peto class, we present saddlepoint approximations for the exact permutation mid‐P‐values which achieve extremely small relative errors. The speed and stability of these saddlepoint computations make them practicable for inverting the permutation tests and we compute nominal confidence intervals for the treatment effect. Such confidence intervals are of substantial clinical importance since, more than simply stating the level of statistical significance, they quantify the significant benefit of the treatment by providing a confidence interval for the percentage increase in mean (or median) treatment survival time as compared to control. Our methodology makes heavy use of nonparametric MLEs (NPMLEs) for survival functions and some limitations of existing algorithms, such as the hybrid ICM algorithm, are noted and accommodated. The Canadian Journal of Statistics 42: 308–324; 2014 © 2014 Statistical Society of Canada

Anal sac tumours of the dog and their response to cytoreductive surgery and chemotherapy

A retrospective study of anal sac tumours without pulmonary metastases, from the author's clinical records for the period July 1989 to July 2002, was conducted to establish the response to treatment with surgery and melphalan chemotherapy. Of 21 dogs with tumours of the anal sacs 19 had apocrine gland adenocarcinomas of anal sac origin, one had a benign papillary cystadenoma and another had a malignant melanoma. Two of the 19 dogs had bilateral anal sac adenocarcinomas. Ten of the 19 dogs with apocrine gland adenocarcinomas of anal sac origin had sublumbar lymphadenopathy. Five dogs were excluded by their owners from recommended treatment. Fourteen dogs with apocrine gland adenocarcinomas of anal sac origin were treated by surgical cytoreduction and chemotherapy with melphalan. Seven of the 14 dogs had regional lymph node metastases. Cytoreduction was by local excision of the anal sac in all 14 dogs and concurrent removal of the sublumbar retroperitoneal lymph nodes in the seven dogs with regional lymph node metastases. The median survival time of dogs with sublumbar nodal metastasis was 20 months and for dogs with tumour localised to the anal sac the median survival time was 29.3 months. There was no difference in median survival of those dogs with sublumbar metastases compared to those without. This study suggests there is a role for melphalan in the treatment of dogs with anal sac adenocarcinoma when combined with cytoreductive surgery, with treatment survival times and the local recurrence rate of the primary tumour comparing favourably with previously published treatment regimes.