Monitoring Circulating CD207+CD1a+ Cells in Langerhans Cell Histiocytosis and Clinical Implications.

Langerhans cell histiocytosis (LCH) is a disorder characterized by an abnormal accumulation of CD207+ and CD1a+ cells in almost any tissue. Currently, there is a lack of prognostic markers to follow up patients and track disease reactivation or treatment response. Putative myeloid precursors CD207+ and CD1a+ cells were previously identified circulating in the blood. Therefore, we aim to develop a sensitive tracing method to monitor circulating CD207+ and CD1a+ cells in a drop of blood sample of patients with LCH. A total of 202 blood samples from patients with LCH and 23 controls were tested using flow cytometry. A standardized cellular score was defined by quantifying CD207+ and CD1a+ expression in monocytes and dendritic cells, based on CD11b, CD14, CD11c, and CD1c subpopulations, resulting in a unique value for each sample. The scoring system was validated by a receiver operating characteristic curve showing a reliable discriminatory capacity (area under the curve of 0.849) with a threshold value of 14, defining the presence of circulating CD207+ and CD1a+ cells. Interestingly, a fraction of patients with no evident clinical manifestation at the time of sampling also showed presence of these cells (29.6%). We also found a differential expression of CD207 and CD1a depending on the organ involvement, and a positive correlation between the cellular score and plasma inflammatory markers such as soluble CD40L, soluble IL-2Ra, and CXCL12. In conclusion, the analysis of circulating CD207 and CD1a cells in a small blood sample will allow setting a cellular score with minimal invasiveness, helping with prognostic accuracy, detecting early reactivation, and follow-up.

Desmoid-type fibromatosis in children. Clinical features, treatment response, and long-term follow-up

Desmoid-type fibromatosis (DF) is a tumor with high local recurrence rate. Sixteen patients (18 desmoid tumors) were retrospectively evaluated. Initial surgery was performed in 13/18 tumors, with complete resection in 6 (one with free margin and five with microscopic residual disease); 10/13 had local relapse. Eleven patients with 13 tumors underwent treatment with methotrexate-vinblastine. The response rate to chemotherapy was 54%, and up to 81% if stable disease cases were included. The best response was partial remission. Only 2 had grade 4 toxicity. Twelve of 15 patients had sequelae. In 8 cases sequelae were directly related to the surgical intervention and 3 of them were severe. The 5-year progression-free survival and overall survival were 30% and 93.3%, respectively. DF has a high local relapse rate, regardless of surgical margin involvement. Low dose chemotherapy achieved stable disease and even remission of the lesions with low toxicity. The high rate of sequelae is probably related to the initial surgery performed in the majority of patients and may be avoided by the use of neoadjuvant low dose chemotherapy.

La fibromatosis tipo desmoide (FD) es un tumor con alta tasa de recurrencia local. Dieciséis pacientes (18 tumores desmoides) fueron evaluados retrospectivamente. La cirugía inicial se realizó en 13/18 tumores, con resección completa en 6 (uno con margen libr e y cinco con margen microscópicamente comprometido); 10/13 tuvieron recaída local. Once pacientes con 13 tumores recibieron tratamiento con metotrexato/ vinblastina. La tasa de respuesta a la quimioterapia fue del 54% y de hasta el 81% si se incluyen los casos que lograron enfermedad estable. La mejor respuesta fue remisión parcial. Solo 2 tuvieron toxicidad grado 4. Doce de 15 pacientes tuvieron secuelas. En 8 casos, las secuelas estuvieron directamente relacionadas con la intervención quirúrgica y 3 de ellas fueron graves. La sobrevida libre de progresión a 5 años y la supervivencia global fueron del 30% y del 93.3%, respectivamente. La FD tiene una alta tasa de recaída local, independientemente del margen quirúrgico. Dosis bajas de quimioterapia lograron una enfermedad estable e incluso la remisión de las lesiones, con baja toxicidad. La alta tasa de secuelas probablemente esté relacionada con la cirugía inicial realizada en la mayoría de los pacientes y podría evitarse mediante el uso de quimioterapia neoadyuvante en dosis bajas, como sugieren las estrategias actuales de tratamiento.

Desmoid-type fibromatosis in children. Clinical features, treatment response, and long-term follow-up / Fibromatosis tipo desmoide en niños. Características, respuesta al tratamiento y seguimiento a largo plazo

Abstract Desmoid-type fibromatosis (DF) is a tumor with high local recurrence rate. Sixteen patients (18 desmoid tumors) were retrospectively evaluated. Initial surgery was performed in 13/18 tumors, with complete resection in 6 (one with free margin and five with microscopic residual disease); 10/13 had local relapse. Eleven patients with 13 tumors underwent treatment with methotrexate-vinblastine. The response rate to chemotherapy was 54%, and up to 81% if stable disease cases were included. The best response was partial remission. Only 2 had grade 4 toxicity. Twelve of 15 patients had sequelae. In 8 cases sequelae were directly related to the surgical intervention and 3 of them were severe. The 5-year progression-free survival and overall survival were 30% and 93.3%, respectively. DF has a high local relapse rate, regardless of surgical margin involvement. Low dose chemotherapy achieved stable disease and even remission of the lesions with low toxicity. The high rate of sequelae is probably related to the initial surgery performed in the majority of patients and may be avoided by the use of neoadjuvant low dose chemotherapy.

Resumen La fibromatosis tipo desmoide (FD) es un tumor con alta tasa de recurrencia local. Dieciséis pacientes (18 tumores desmoides) fueron evaluados retrospectivamente. La cirugía inicial se realizó en 13/18 tumores, con resección completa en 6 (uno con margen libre y cinco con margen microscópicamente comprometido); 10/13 tuvieron recaída local. Once pacientes con 13 tumores recibieron tratamiento con metotrexato/vinblastina. La tasa de respuesta a la quimioterapia fue del 54% y de hasta el 81% si se incluyen los casos que lograron enfermedad estable. La mejor respuesta fue remisión parcial. Solo 2 tuvieron toxicidad grado 4. Doce de 15 pacientes tuvieron secuelas. En 8 casos, las secuelas estuvieron directamente relacionadas con la intervención quirúrgica y 3 de ellas fueron graves. La sobrevida libre de progresión a 5 años y la supervivencia global fueron del 30% y del 93.3%, respectivamente. La FD tiene una alta tasa de recaída local, independientemente del margen quirúrgico. Dosis bajas de quimioterapia lograron una enfermedad estable e incluso la remisión de las lesiones, con baja toxicidad. La alta tasa de secuelas probablemente esté relacionada con la cirugía inicial realizada en la mayoría de los pacientes y podría evitarse mediante el uso de quimioterapia neoadyuvante en dosis bajas, como sugieren las estrategias actuales de tratamiento.