Treating Anal Cancer With Smarter and Kinder Approach

Recent clinical trial results have shown that reducing the dose and duration of radiotherapy treatments for anal cancer may result in fewer side effects.

Three clinical trials designed to optimize radiotherapy treatment for patients with anal cancer show that reducing the dose and duration may result in fewer side effects. The trials were conducted in a study, called PLATO at the University of Leeds and is funded by Cancer Research UK and Stand Up To Cancer.

This first clinical trial in the world to randomize patients between standard and lower dose treatment in anal cancer. The short-term findings have been presented at the 2023 European Society for Therapeutic Radiology and Oncology (ESTRO) Congress, the largest European radiotherapy conference.

Role of Radiotherapy in Anal Cancer

Anal cancer is a rare disease with roughly 1,500 cases diagnosed in the UK every year but the incidence of the disease is set to rise by 14% over the next 15 years (). The current standard of care for anal cancer is chemo-radiotherapy.

Anal Cancer | Cancer of Anal - Causes, Symptoms, Staging, Treatment, Prognosis & Prevention
Cancer of the anus is rare however its incidence is increasing especially among the HIV positive patients and it is caused by human papilloma (HPV) virus.

‘lower dose radiotherapy completely disappears anal cancer with fewer side effects and improved sexual function than the standard dose.’

While this practice results in relatively high cure rates there are significant side effects as a result. Some of the most common side effects of radiotherapy include sore skin, diarrhea, incontinence, fatigue, vaginal irritation, and loss of sexual function.

The global standard of care for anal cancer has not changed for more than two decades. The current approach is associated with significant short-term and long-term side effects and high-quality evidence is required to determine the best dose of radiotherapy for tumors of different sizes and the degree of local spread ().

Optimizing Radiotherapy Treatment for Patients with Anal Cancer

Despite its rarity, researchers can complete clinical trials to provide vital evidence that will help decide the best treatment for future patients with anal cancer and help preserve their quality of life.

Hence, new trials determined whether a lower dose, shorter course of radiotherapy combined with chemotherapy can reduce the short-term and long-term side effects of treatment and still achieve the same high rate of local eradication of cancer that is achieved using a standard dose of radiotherapy combined with chemotherapy.

Radiation Therapy can Improve Lives of Anal Cancer Patients
Combination of extended-field radiation therapy and chemotherapy and intensity modulated radiation therapy (IMRT) improves overall survival in anal cancer without increasing the risk of side effects.

The research team observed that at six months a lower dose of radiotherapy resulted in a high level of complete disappearance of the cancer with fewer side effects and improved sexual function than observed for patients receiving standard dose treatment.

Across both groups there was a high rate of complete response of the cancer at six months - meaning all signs of cancer had disappeared in response to treatment for both low and standard doses of radiotherapy ().

New Study on Connection Between Anal Cancer and Human Papillomavirus
A study demonstrating a connection between anal cancer and HPV infection has been published by researchers at Women & Infants Hospital, a Care New England hospital.

Further follow-up is required to determine the impact of lower dose radiotherapy on local recurrence of anal cancer and the results are expected next year.

The side effects of radiotherapy treatments have a significant impact on the lives of patients and their friends and families. These clinical trial results using lower-dose radiotherapy are very encouraging.

Providers' Attitude on Vaccinating Young Males Against HPV May Defy New Proposal
Health care provider's attitude concerning male human papillomavirus (HPV) vaccination could affect the implementation of new guidelines find researchers from BUSM.

The current approach for anal cancer treatments is essentially a ‘one size fits all’ where the dose of radiotherapy is similar whether the tumor being treated is very small or very large. If we could offer tailored approaches without compromising cure rates, this could prevent patients from suffering side effects unnecessarily.

The PLATO’s trial results are an important step towards a personalized approach for anal cancer and using a smarter, kinder approach to treatment.

References:

Anal Cancer - (https://pubmed.ncbi.nlm.nih.gov/32402305/)
Management of anal cancer patients – a pattern of care analysis in German-speaking countries - (https://ro-journal.biomedcentral.com/articles/10.1186/s13014-020-01539-x)
Current treatment and future directions in the management of anal cancer - (https://acsjournals.onlinelibrary.wiley.com/doi/10.3322/caac.21712)

Source-Eurekalert