Background: Dedifferentiated chordoma (DC) is a biphasic malignant tumor, that occurs almost exclusively in recurrent disease or after radiotherapy treatment, with a strong predilection for sacrum area. DC localized in the clivus are extremely rare and limited to a case report. Design: We investigated the morphological, immunohistochemical features of 6 DCs of the clivus and their clinical behavior in patients treated in a single institution between 1998 and 2017. Results: These 6 cases (4 males, 2 females) represent 8.1% of series of 74 clivus chordoma surgically treated in our institution. Age ranged from 35 to 64 years (mean: 46 years). Three out of these 6 patients have been previously undergone surgery followed to radiotherapy with a histological diagnosis of chordoma without areas of dedifferentiation, whereas in two other cases a biopsy was done in other centers with a diagnosis of classic chordoma. Five patients had diplopia, one patient had dysphasia and hemiparesis and the remaining case had dysphagia. DCs were extradural in 5 cases, and only one presented an intradural extension. All cases were operated through an endoscopic endonasal approach with a subtotal tumor removal in 3 cases, and a partial tumor removal in 3 cases. Morphologically, all cases showed two distinct components: a classic chordoma juxtaposed to dedifferentiated component without notochordal differentiation constituted to high grade undifferentiated spindle or pleomorphic sarcoma. Immunohistochemically, the tumor cells of classic chordomas component were positive for brachyury, S-100 protein, and epithelial markers including pan-cytokeratins and EMA; whereas dedifferentiated tumor cells were negative for all markers examined, including also muscle markers (smooth muscle actin, desmin, h-caldesmon and myogenin) and osteogenic marker SATB2. INI1 protein nuclear expression, that is usually lost in poorly differentiated chordoma, was maintained in both components of all 6 cases. All patients were treated with proton beam therapy or other radiotherapies after surgery. One patient presented a consistent progression of the remnant after 12 months, which requires a second surgery through the same approach. All patients died of disease with tumor progression after a mean of 29 months (range from 11to 52 months). Conclusions: DC is not so rare aggressive neoplasm in the clivus, resistant to conventional radiation treatment. It usually developed from recurrence or progression of a classic chordoma after surgical approach or radiation therapy, although de novo cases exist
Asioli, S., Righi, A., Ambrosi, F., Ricci, C., Zoli, M., Pasquini, E., et al. (2019). Dedifferentiated Chordoma of the Clivus: A Monocentric Experience. MODERN PATHOLOGY, 32, 2-2.
Dedifferentiated Chordoma of the Clivus: A Monocentric Experience
Asioli, S;Ambrosi, F;Ricci, C;Zoli, M;Mazzatenta, D;Foschini, M
2019
Abstract
Background: Dedifferentiated chordoma (DC) is a biphasic malignant tumor, that occurs almost exclusively in recurrent disease or after radiotherapy treatment, with a strong predilection for sacrum area. DC localized in the clivus are extremely rare and limited to a case report. Design: We investigated the morphological, immunohistochemical features of 6 DCs of the clivus and their clinical behavior in patients treated in a single institution between 1998 and 2017. Results: These 6 cases (4 males, 2 females) represent 8.1% of series of 74 clivus chordoma surgically treated in our institution. Age ranged from 35 to 64 years (mean: 46 years). Three out of these 6 patients have been previously undergone surgery followed to radiotherapy with a histological diagnosis of chordoma without areas of dedifferentiation, whereas in two other cases a biopsy was done in other centers with a diagnosis of classic chordoma. Five patients had diplopia, one patient had dysphasia and hemiparesis and the remaining case had dysphagia. DCs were extradural in 5 cases, and only one presented an intradural extension. All cases were operated through an endoscopic endonasal approach with a subtotal tumor removal in 3 cases, and a partial tumor removal in 3 cases. Morphologically, all cases showed two distinct components: a classic chordoma juxtaposed to dedifferentiated component without notochordal differentiation constituted to high grade undifferentiated spindle or pleomorphic sarcoma. Immunohistochemically, the tumor cells of classic chordomas component were positive for brachyury, S-100 protein, and epithelial markers including pan-cytokeratins and EMA; whereas dedifferentiated tumor cells were negative for all markers examined, including also muscle markers (smooth muscle actin, desmin, h-caldesmon and myogenin) and osteogenic marker SATB2. INI1 protein nuclear expression, that is usually lost in poorly differentiated chordoma, was maintained in both components of all 6 cases. All patients were treated with proton beam therapy or other radiotherapies after surgery. One patient presented a consistent progression of the remnant after 12 months, which requires a second surgery through the same approach. All patients died of disease with tumor progression after a mean of 29 months (range from 11to 52 months). Conclusions: DC is not so rare aggressive neoplasm in the clivus, resistant to conventional radiation treatment. It usually developed from recurrence or progression of a classic chordoma after surgical approach or radiation therapy, although de novo cases existI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
