Studies have shown that continuous radiotherapy is safe and effective as an alternative to the systemic treatment of kidney cancer

The RCC Oligometastasis Phase II trial is the first study to investigate and report the use of stereotactic radiotherapy (SBRT) as an alternative treatment standard treatment systemic treatment of oligometastatic roller compacted concrete, a small number of new RCC tumors in the body of one or two other A disease state formed by the site
.

A series of SBRT monotherapy in patients with RCC (the most common type of kidney cancer) showed anti-tumor activity and achieved a median progression-free survival (PFS) of 22.

"These findings are exciting because we challenge the dogma of radiation oncology that RCC is biologically resistant to radiation," Tang said
.

"Our strategy is to repeat radiation as the tumor grows and appears.

SBRT uses high-dose radiation to precisely treat the tumor site without damaging the surrounding healthy tissue
.

SBRT is a non-invasive local treatment method that maps the position and shape of the tumor and determines its exact angle and intensity under the guidance of advanced imaging technologies such as computed tomography (CT) and magnetic resonance imaging (MRI).

For kidney cancer patients, radiotherapy is more often used as a palliative therapy to relieve pain or control symptoms, while systemic treatments (such as immunotherapy and targeted drugs) are often used as first-line treatments
.

Although systemic therapy drugs are very effective, they affect the entire body and are associated with a large number of toxicities

"By developing this new type of radiation therapy strategy, we are trying to change the treatment model and strive to provide selected RCC patients with a lower cost and less toxic alternative treatment than systemic therapy," Tang said
.

From July 2018 to September 2020, the researchers recruited 30 patients with renal cell carcinoma diagnosed as clear cell subtypes with 5 or fewer metastatic lesions
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The trial included 20 whites (67%), 7 Hispanics (23%), 2 blacks (7%) and 1 Indian (3%)

In general, radiation therapy is well tolerated and treated conservatively
.

All patients completed at least one round of radiotherapy, and no dose reduction or treatment was stopped due to toxicity

Biopsy collected three months after treatment confirmed that radiotherapy is effective in eliminating live tumor cells or significantly reducing their proliferation
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In the first follow-up, the researchers performed CT-guided biopsy on 14 patients

Although more large-scale randomized trials are needed to further study the risks and benefits of SBRT as a monotherapy, the study shows that radiotherapy is feasible for the treatment of less metastatic renal cell carcinoma, and has produced good results and minimal toxicity
.

"In view of these results, I am encouraged that continuous radiotherapy for less metastatic renal cell carcinoma has the potential to change practice," Tang said
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"We are providing patients with another treatment option to minimize the toxic burden on the body, while prolonging survival time and maximizing their quality of life

This trial was supported by the Anna Fuller Foundation, the Cancer Prevention and Research Institute of Texas (CPRIT), and the National Cancer Institute
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Pavlos Msaouel, MD, assistant professor of genitourinary medical oncology, co-first author, Nizar Tannir, MD, professor of genitourinary medical oncology, senior author
.

Journal Reference :

1. Chad Tang, Pavlos Msaouel, Kieko Hara, Haesun Choi, Venus Le, Amishi Y Shah, Jennifer Wang, Eric Jonasch, Seungtaek Choi, Quynh-nhu Nguyen, Prajnan Das, Surendra Prajapati, Zhiqian Yu, Khaja Khan, Steven Powell, Ravi Murthy , Kanishka Sircar, Nizar M Tannir.
   Definitive radiotherapy in lieu of systemic therapy for oligometastatic renal cell carcinoma: a single-arm, single-centre, feasibility, phase 2 trial .
   The Lancet Oncology , 2021; DOI: 10.
   1016/S1470-2045( 21)00528-3