The CRIS Against Cancer Foundation has highlighted its support for research, both in Spain and abroad, in the field of sarcomas, through projects focused on improving diagnosis and accelerating the arrival of new therapies for tumors that, in its opinion, constitute one of the most complex challenges in oncology due to their low frequency and high complexity.
Coinciding with International Sarcoma Day, which is commemorated on July 13, the entity recalls some of the projects it is financing. Among them, the development of next-generation cell therapies for children with sarcomas who have no therapeutic alternatives at the La Paz University Hospital (Madrid).
The foundation also promotes the identification of biomarkers that help predict the appearance of metastases and adapt treatments at the Virgen del Rocío University Hospital (Seville) and INCLIVA (Valencia). Similarly, it emphasizes the exhaustive research into the genetic basis of sarcomas in order to refine diagnosis and detect new therapeutic targets at the Vall d'Hebron Oncology Institute (VHIO, Barcelona).
Sarcomas encompass a group of tumors that originate in the tissues that support and structure the body: bones, muscles, adipose tissue, blood vessels, nerves, and other support tissues. Unlike more common cancers, which usually appear in cells that line organs or body surfaces, sarcomas can arise in multiple locations and take on very diverse forms.
In reality, the term sarcoma does not hide a single pathology, but a broad family of tumors with more than 150 subtypes: from osteosarcoma or Ewing's sarcoma, which affect bone, to synovial sarcoma, rhabdomyosarcomas, and numerous soft tissue sarcomas.
This enormous heterogeneity is one of the reasons that has led CRIS Against Cancer to prioritize research into sarcomas. They are rare tumors—around 2,600 cases are diagnosed annually in Spain and about 28,000 in the entire European Union—but their rarity does not mean they are a minor problem.
When the disease is detected in localized stages, a significant portion of patients respond adequately to treatment. However, if the sarcoma progresses, recurs, or stops responding to available therapies, the prognosis deteriorates very markedly: 5-year survival in soft tissue sarcomas drops from 83 percent in localized disease to approximately 17 percent in metastatic situations, and in some relapsed or resistant childhood sarcomas, it can fall below 10-30 percent, depending on the subtype.
Three major challenges for sarcoma research
According to CRIS Contra el Cáncer, there are three main reasons why sarcomas pose a particularly complex challenge for medicine, and its strategy is aimed at addressing them. Firstly, its low incidence stands out: by affecting a small number of patients, it is more difficult to gather sufficient samples, generate solid knowledge, and launch specific clinical trials for each subtype.
Secondly, the Foundation emphasizes the enormous diversity of these tumors. Sarcoma is not a single disease, but a broad group of very different neoplasms that, even within the same organ, can show very different genetic and molecular behaviors. Therefore, a single therapeutic strategy rarely works for all cases, and CRIS Contra el Cáncer supports projects that seek to understand each tumor in detail to advance towards more precise and personalized treatments for each patient.
Finally, CRIS Contra el Cáncer highlights the tendency of sarcomas to reappear, spread, or become resistant to treatments. In these scenarios, the available alternatives are significantly reduced, and the prognosis worsens very significantly. Many of the mechanisms by which tumor cells escape or stop responding to therapies are still unknown, which is why the foundation finances studies aimed at better understanding these processes and being able to anticipate them.
Key projects driven by CRIS Contra el Cáncer
In the CRIS Unit for Advanced Therapies for Childhood Cancer at La Paz University Hospital, led by Dr. Antonio Pérez, new immunotherapy strategies are being developed to address pediatric sarcomas.
These works have already reached clinical practice through pioneering trials promoted by the CRIS Unit itself. Among them are therapies based on NK cells from healthy donors and a new generation of CAR-T cells, an approach that consists of genetically modifying T lymphocytes of the immune system so that they can specifically recognize and destroy tumor cells.
On the other hand, the Ewing Sarcoma CRIS Project, led by Dr. Enrique de Álava, director of the Intercenter Clinical Management Unit of Pathological Anatomy at the Virgen del Rocío University Hospital in Seville, and Dr. Rosa Noguera, coordinator of the Translational Research Group on Pediatric Solid Tumors at INCLIVA (Valencia), aims to deepen the biology of these tumors to optimize their diagnosis and slow the appearance of metastases.
The objective of this line of work is to clarify why some Ewing sarcomas and very similar tumors, known as "Ewing-like," show particularly aggressive behavior and develop metastases.
Finally, Dr. César Serrano leads a project at the Vall d'Hebron Institute of Oncology (VHIO) aimed at transforming the way these tumors are diagnosed and classified. Through the molecular analysis of hundreds of patient samples and the use of cutting-edge genomic technologies, his team is identifying alterations that had previously gone unnoticed and that will allow for a more accurate definition of the different sarcoma subtypes.