Multimodality Treatment in Malignant Peripheral Nerve Sheath Tumors
Received Date : 04 Sep 2019
Accepted Date : 15 Dec 2019
Available Online : 10 Feb 2020
Yusuf KARAKAŞa, Ömer DİZDARb, Kemal KÖSEMEHMETOĞLUc, Utku Burak BOZBULUTb, Metin DEMİRb, Gökhan GEDİKOĞLUc, Figen SÖYLEMEZOĞLUc, Alev TÜRKERb, Ayşe KARSb
aAcıbadem Bodrum Hospital, Clinic of Medical Oncology, Muğla, Turkey
bHacettepe University Oncology Institute, Department of Medical Oncology, Ankara, Turkey
cHacettepe University Faculty of Medicine, Department of Pathology, Ankara, Turkey
Doi: 10.37047/jos.2019-73127 - Article's Language: EN
J Oncol Sci. 2020;6(1):23-8
ABSTRACT
Objective: Malignant peripheral nerve sheath tumors (MPNSTs) are rare soft tissue sarcomas with poor prognosis. The treatment
options, especially in metastatic cases, are limited. In this study, we aimed to investigate the treatment outcomes along with programmed
death-ligand 1 (PD-L1) expression as a potential surrogate for immunotherapy benefit in our patients with MPNST. Material and Methods:
In this retrospective study, 27 patients diagnosed with MPNST and treated at the Hacettepe University Cancer Institute between 2000 and 2016
were evaluated. Patient and tumor characteristics, survival data and treatment modalities were obtained from medical charts. The patient outcomes
were assessed based on the treatment modality. Slides prepared from 4-mm diameter microarray tissue were stained for the PD-L1 antibody
using Leica Bond Autostainer (Cell Signaling, E1L3N®). Membranous staining more than 5% of the cells were accepted as positive.
Results: The median age of the patients was 36 years (range 19-89 years), and 37% of patients were male. The median tumor size was 8.7
cm, and 62% of patients had high-grade tumors. The most common tumor localizations were extremities (41%), trunk (48%), and the headneck
region (11%). Only two patients (7%) had distant metastases at the time of diagnosis. Seven patients (26%) had neurofibromatosis type
1 (NF1) and the presence of NF-1 was associated with partially worse overall survival (p=0.056). The majority of the patients underwent primary
surgery (96.3%), and R0-R1 resection was achieved by 76% of patients. The median follow-up was 16 months (range 1 to 178 months).
During the follow-up, 16 patients (59%) had recurrence (37% local, 22% distant recurrence). A 3-year disease-free survival (DFS) rate according
to R0-R1 and R2 resection was 57% vs. 17%, respectively (p<0.001). After surgery, 48% of the patients received adjuvant therapy.
Two patients (7%) received only chemotherapy, five patients (19%) received only radiotherapy (RT), and six patients (22%) received both.
Patients who received both chemotherapy and RT had longer DFS compared to those who received either therapy alone and to those who received
no adjuvant therapy (3-year DFS 100% vs. 14% vs. 44%, respectively, p=0.003) (Figure 3). PD-L1 expression was positive in 6 of 15
patients (40%) and was not associated with DFS. Conclusions: Multimodality treatment with surgery, chemotherapy, and RT may improve
DFS in patients with MPNSTs. The PD-L1 expression is not associated with DFS.
Keywords: Malignant peripheral nerve sheath tumor; multimodality treatment; PD-L1 expression