Radioterapia en tumor de células gigantes tenosinovial (sinovitis villonodular pigmentada) / Radiation therapy in tenosynovial giant cell tumor (pigmented villonodular synovitis)

Presentar nuestra experiencia de 18 años en el tratamiento con radioterapia y evaluar cifras de control tumoral local en pacientes con diagnóstico de tumor de células gigantes tenosinovial difuso sinovitis villonodular pigmentada difusa. 33 pacientes, tratados durante el período 2000-2018. En 19 (57,6 %) se practicó sinovectomía parcial, 10 (30,3 %) fueron tratados con artroplastia y sinovectomía, 4 (12,2 %) con sinovectomía total. 32 pacientes recibieron radioterapia posoperatoria, 1 paciente preoperatoria. Técnica más empleada fue planificación 2D 51,5 % seguida de conformada con planificación 3D (RTC3D) 48,5 %. La dosis total promedio administrada 44 Gy (rango 10,5 - 50). Tiempo promedio de tratamiento radiante 28 días (8-35). Tiempo de seguimiento entre 0,7 - 240,8 meses, mediana 12 meses, promedio 52,1 meses. 26 pacientes (79 %) presentaron mejoría de la sintomatología inicial y 6 (18 %) refirieron estabilidad de los síntomas. La respuesta clínica al tratamiento en relación al tiempo de seguimiento, 12 pacientes (36,4 %) estaban asintomáticos, 10 con un seguimiento mayor a 60 meses; 14 (42,4 %) refieren respuesta clínica satisfactoria, (2 con un seguimiento mayor a 60 meses) 6 pacientes presentaban enfermedad estable, para un control local del 97 %. El 87,9 % presentaron dermatitis grado I, 1 desarrolló dermatitis grado II, 3 no presentaron efectos adversos. La radioterapia es una modalidad de tratamiento muy efectiva como adyuvante a la sinovectomía, observándose altas tasas de control local de la enfermedad con una baja morbilidad(AU)

To report our eighteen-year experience with radiation therapy in the treatment of diffuse tenosinovial giant cell tumor / diffuse pigmented villonodular synovitis and to assess local control of the disease. A review of 33 patients with treated with radiation therapy during the period 2000-2018 was done. 19 (57.6 %) partial synovectomy was performed, 10 (30.3 %) underwent arthroplasty plus synovectomy, 4 (12.2 %) total synovectomy. 32 patients received radiotherapy postoperative and 1 pre-operative. Most common technique employed was conventional (2D) in 51.5 % and 3D conformal (3DCRT) in 48.5 %. The average total dose was 44 Gy (range 10.5-50), with a mean treatment time of 28 days (8-35). Follow-up time ranged from 0.7- 240.8 months, median time and mean time of 12 and 52.1 months respectively After RT 26 (79 %) of the patients obtained improvement of the initial symptoms and 6 (18 %) were stable. 12 patients (36.4 %) were asymptomatic with follow-up time longer than 36 months (10 of 12 had follow-up time >60 months), 14 (42.4 %) had significant clinical improvement (2 of 14 had follow-up time >60 months), and 6 had stable disease, local control of 97 %. Complications were few, acute skin toxicity was grade I in 29 (87.9%) and grade II in 1 patient. There was no significant chronic toxicity. Radiation therapy is an effective adjuvant treatment modality after synovectomy in patients with high local control rates and low morbidity(AU)

Pexidartinib: first approved systemic therapy for patients with tenosynovial giant cell tumor.

Pexidartinib is an orally administered small molecule tyrosine kinase inhibitor. Phase III ENLIVEN study results provided clinical evidence for US FDA approval for treatment of adult patients with symptomatic tenosynovial giant cell tumor associated with severe morbidity or functional limitations and not amenable to improvement with surgery. Recommended dosage is 400 mg orally twice daily on an empty stomach. Long-term follow-up in pooled analyses showed increased response rates compared with those observed in ENLIVEN. Patients on pexidartinib also experience meaningful improvements in range of motion. Side effects associated with pexidartinib are generally manageable; however, there is a risk of potentially life-threatening mixed or cholestatic hepatotoxicity and pexidartinib has a Risk Evaluation and Mitigation Strategy (REMS) program to ensure appropriate monitoring.

Giant cell tumor of the tendon sheath arising from a membrane surrounding the posterior arch of C1: a case report.

BACKGROUND CONTEXT: Giant cell tumor of the tendon sheath (GCTTS) is a common, benign lesion of the synovial membrane that occurs more often in large joints than in digits. Giant cell tumor of the tendon sheath rarely arises in close proximity to the axial skeleton. PURPOSE: The purpose of the study was to report a rare case of GCTTS arising from the membrane surrounding the posterior arch of the atlas (C1). STUDY DESIGN/SETTING: This is a case report. METHODS: The methods involve clinical findings and review of current literature. RESULTS: In this report, we describe a rare case of GCTTS arising from the membrane surrounding the posterior arch of C1, with no apparent continuity with the facet joint. Here we show the radiographic features, with particular emphasis on positron emission tomography-computerized tomography scans, which have not been previously reported. CONCLUSIONS: We experienced an extremely rare case of GCTTS arising from the membrane surrounding the posterior arch of the C1 vertebra. In spite of the rarity of this disease, GCTTS should be considered in the differential diagnosis of the axial skeletal lesion. Awareness of GCTTS is important because its radiographic features may simulate other neoplastic lesions in the spine.