Therapeutic strategies and clinical evolution of patients with infantile fibrosarcoma: a unique paediatric case series

BACKGROUND

Infantile fibrosarcoma is the most frequent soft tissue sarcoma in newborns or children under one year of age. This tumour often implies high local aggressiveness and surgical morbidity. The large majority of these patients carry the ETV6-NTRK3 oncogenic fusion. Hence, the TRK inhibitor larotrectinib emerged as an efficacious and safe alternative to chemotherapy for NTRK fusion-positive and metastatic or unresectable tumours. However, real-world evidence is still required for updating soft-tissue sarcoma practice guidelines.

OBJECTIVE

To report our experience with the use of larotrectinib in pediatric patients.

METHODS

Our case series shows the clinical evolution of 8 patients with infantile fibrosarcoma under different treatments. All patients enrolled in this study received informed consent for any treatment.

RESULTS

Three patients received larotrectinib in first line. No surgery was needed with larotrectinib, which led to the rapid and safe remission of tumours, even in unusual anatomical locations. No significant adverse effects were observed with larotrectinib.

CONCLUSION

Our case series supports that larotrectinib may be a therapeutic option for newborn and infant patients with infantile fibrosarcoma, especially in uncommon locations.

Treatment of infantile fibrosarcoma associated to an abdominal aortic aneurysm with larotrectinib: a case report

Infantile fibrosarcoma (IFS) is a rare pediatric tumor which often presents the ETV6-NTRK3 gene fusion. NTRK3 encodes the neurotrophin-3 growth factor receptor tyrosine kinase, a druggable therapeutic target. Selective tropomyosin receptor kinase (TRK) inhibitors, such as larotrectinib, have shown efficacy and safety in the treatment of IFS. We report a case of an abdominal IFS diagnosed in a newborn associated with an aortic aneurysm that was successfully treated with larotrectinib without relevant adverse effects.

Beyond CAR-T cells: Natural killer cells immunotherapy

Children and adolescents suffering from refractory leukaemia, relapse after stem cell transplantation, solid metastatic tumour or refractory to conventional treatments still condition a dismal prognosis. The critical role of the immune system in the immunosurveillance of cancer is becoming relevant with the development of new treatments such as the checkpoint inhibitor drugs and genetic modified T lymphocytes, tisagenlecleucel or axicabtagene ciloleucel. In addition, other immunotherapies are being developed such as cell therapy with natural killer (NK) lymphocytes. The rapid and potent cytotoxic activity of NK cells respecting healthy cells and the possibility of expansion, manipulating them and combining them with other treatments, make these cells a powerful therapeutic tool to be developed, with a very high safety profile. Furthermore, new strategies are being developed to increase the therapeutic benefit of NK cells such as genetic manipulation for the expression of chimeric antigen receptors.

Anhydrobiosis quotient: a novel approach to evaluate stability in desiccated bacterial cells

AIM

The major objective of this study was the development of a methodology to quantify the anhydrobiotic ability of bacteria and its application to evaluate the stability of desiccated bacterial cells using the biocontrol agent Tsukamurella paurometabola C-924 as a model of anhydrobiote.

METHODS AND RESULTS

Tsukamurella paurometabola C-924 was desiccated by spray-drying. Samples of desiccated cells were stored at several temperatures and viability and residual moisture were measured at different intervals of time. The term anhydrobiosis quotient (epsilon) was defined, and a scale of anhydrobiotic ability for classifying micro-organisms in terms of tolerance to desiccation was established (1 < or = epsilon < or = 15). The anhydrobiosis quotient was used to evaluate the stability of the anhydrobiotic cells. As a main result, changes in the anhydrobiosis quotient at several temperatures were fitted using a reparameterized Weibull model, which was found to be robust for the prediction of the stability at 4 degrees C.

CONCLUSIONS

A novel methodology was developed to evaluate the desiccated state in bacteria. The anhydrobiosis quotient allows the quantitative estimation of the anhydrobiotic ability, and the mathematical model developed allows the prediction of the desiccated state of bacterial populations.

SIGNIFICANCE AND IMPACT OF THE STUDY

The new methodology could be applied in studying the anhydrobiosis state of bacterial populations as a predictive tool for industrial and environmental microbiology.