Clinical Image
Secondary Soft Tissue Sarcoma after Carbon Ion Radiotherapy for Sacral Chordoma
Yasuhiro Yamamoto*
Department of Orthopaedics Surgery, School of Medicine, Fujita Health University, Japan
*Corresponding author: Yasuhiro Yamamoto, Department of Orthopaedics Surgery, School of Medicine, Fujita Health University, Japan
Published: 05 Dec, 2017
Cite this article as: Yamamoto Y. Secondary Soft Tissue
Sarcoma after Carbon Ion Radiotherapy
for Sacral Chordoma. Clin Oncol. 2017;
2: 1385.
Keywords
Chordoma; Post-radiation sarcoma; Carbon ion radiotherapy
Clinical Image
Highly malignant sarcomatoid areas rarely observed in cases of chordoma are post-radiation,
sarcomatoid chordoma, dedifferentiated chordoma. In this report, we describe a case with secondary
soft tissue sarcoma after carbon ion radiotherapy (CIRT) for sacral chordoma.
A 73-year-old man complained of having pain in his bottom for two years. Radiorogical
examinations revealed a sacral tumor and histological diagnosis from a needle biopsy specimen was
chordoma.
CIRT was performed for this lesion and the volume of tumor shrank remarkably (Figure1),
but multiple subcutaneous tumors were seen in the subcutaneous adipose tissue in the irradiation
area in five years after CIRT (Figure 2). We performed resectional biopsy for the one of them and
histological diagnosis was pleomorphic sarcoma. Initially, we diagnosed dedifferentiated chordoma
and its subcutaneous metastasis, and we resected the sacral bone below at the level of S2 including
the pleomorphic sarcoma lesions. We concluded the secondary soft tissue sarcoma arising in the
subcutaneous after CIRT for chordoma and its skip lesions because we were not able to detect the
continuously of these two conditions in pathological examination.
Soft tissue sarcoma arising after CIRT for chordoma has not been reported and we should
carefully follow up patients who had CIRT therapy.
Figure 1
Figure 1
a: Before CIRT. A T2-weighted image on examination demonstrated large sacral chordomainvasing
up to S2; b: 3 years after CIRT; c: 5 years afret CIRT.