The impact of sirolimus therapy on lesion size, clinical symptoms, and quality of life of patients with lymphatic anomalies

Abstract

Background: Lymphatic anomalies (LAs) include several disorders in which abnormal lymphatic tissue invades the neck, chest, and various organs. Progressive cases may result in lethal outcomes and have proven difficult to treat. Sirolimus is showing promising results in the management of vascular anomalies. We examined the efficacy and safety of sirolimus treatment in patients with progressive LAs.

Methods: All patients with LAs treated with sirolimus from May 2015 to September 2018 were included. They received oral sirolimus once a day and the dose was adjusted so that the trough concentration remained within 5-15 ng/mL. We prospectively reviewed the response to drugs (the response rate of radiological volumetric change of the target lesion), severity scores, reported quality of life (QOL), and adverse effects at 6 months after administration.

Results: Twenty patients (five with cystic lymphatic malformation (LM), three with kaposiform lymphangiomatosis, three with generalized lymphatic anomaly, six with Gorham-Stout disease, and three with central conducting lymphatic anomaly) were treated with sirolimus at our institution. Fifty percent of patients (10/20) demonstrated a partial response by a radiological examination and a significant improvement in disease severity and QOL scores (P = 0.0020 and P = 0.0117, respectively). Ten patients who had no reduction in lesion size (stable disease group) showed no significant improvement in disease severity and QOL scores. Eighty percent of patients (16/20) had side effects, such as stomatitis, infection, and hyperlipidemia.

Conclusions: Sirolimus impacts the reduction of the lymphatic tissue volume of LMs and could lead to improvement in clinical symptoms and QOL.

Trial registration: UMIN Clinical Trials Registry, UMIN000016580 . Registered 19 February 2015.

Keywords: Generalized lymphatic anomaly; Gorham-stout disease; Lymphatic malformation; Mammalian target of rapamycin; Vascular malformations.

Fig. 1

Volumetric change shown using radiological examination in patients 6 months following the start of sirolimus treatment

Fig. 2

Clinical photograph, MRI, and volumetric measurements for case number 2. A 2-week-old girl had a giant cystic LM lesion in her right neck, axilla, trunk, and abdominal cavity. a-c Pretreatment. d-f 3 months after administration of sirolimus. g-i 6 months after administration of sirolimus. c, f, and i show volumetric measurements evaluated using the Digital Imaging and Communications in Medicine (DICOM) viewer (OsiriX)

Fig. 3

MRI and volumetric measurements for case number 7. An 8-year-old boy with KLA suffered from severe scoliosis, pain, thrombocytopenia, and coagulopathy. T2-weighted MRI of the chest demonstrates diffuse thickening of the interlobular septa and retroperitoneal soft tissue mass, which is the target lesion. a and b Pretreatment. c and d 6 months after administration of sirolimus. b and d show the volumetric measurements evaluated using the Digital Imaging and Communications in Medicine (DICOM) viewer (OsiriX)