Sonographic Features of Extra-articular Giant Cell Tumor of the Tendon Sheath

關節外腱鞘巨細胞瘤之超音波表徵

林理涵(Li-Han Lin) ； 黃宗正(Chung-Cheng Huang) ； 高常發(Sheung-Fat Ko) ； 黃玄贏(Hsuan-Ying Huang) ； 王俊聞(Jun-Wen Wang) ； 鄭汝汾(Yu-Fan Cheng) ； 李子瑜(Tze-Yu Lee)

《中華放射線醫學雜誌》 35卷1期 (2010/03) Pp. 9-16

摘要

此研究目的為回溯性評估關節外腱鞘巨細胞瘤之超音波表徵，並嘗試發展一分類方法以利於鑑別診斷。
從民國95年1月至98年12月間，我們共收集了15個經病理報告證實為關節外腱鞘巨細胞瘤。根據腫瘤位置及其超音波表徵，我們將超音波的表現分為三類：表淺型（腫瘤附著於肌腱但並未將其完全包圍），包圍型（腫瘤完全包圍肌腱），筋膜旁型（腫瘤未附著於肌腱）。各型腫瘤的臨床症狀及超音波表徵均為收集項目。
超音波表現為表淺型，包圍型和筋膜旁型發生率各為46.7%，33.3%和20%。包圍型的腫瘤表現出最大的平均尺寸。表淺型及包圍型腫瘤最常發生於手。所有的腱鞘巨細胞瘤均呈現為均質或非均質的低回音性腫塊。表淺型及包圍型的腫塊偏離中心地附著於相關肌腱上，且腫塊的表淺部份總是為格外顯著。兩個最大的腫塊為包圍型且屬於濔漫型腱鞘巨細胞瘤。
此研究的結論為典型的關節外腱鞘巨細胞瘤之超音波表徵為一均質或非均質的低回音性腫塊且與相鄰的肌腱或筋膜緊密的接觸。當一典型的腫塊表現出大尺寸，分葉狀或不規則的輪廓，完全包圍相關的肌腱和高血管性時，應考慮濔漫型腱鞘巨細胞瘤。此外，一個界限明確且附著於筋膜之腫塊的鑑別診斷應包含筋膜旁型腱鞘巨細胞瘤。

並列摘要

The study aimed to retrospectively review sonographic features of extra-articular giant cell tumor of the tendon sheath (GCTTS), and developed a grouping system for facilitating differential diagnosis. From January 2005 to December 2009, 15 pathologically proven extra-articular GCTTS in 15 patients were encountered in our hospital. According to the tumor sites and their sonographic features, we categorized the sonographic findings into three types: superficial type (tumor attaching to the tendon but no complete encasement of it), encasing type (tumor completely encasing the tendon) and juxta-fascial type (tumor without attachment to the tendon). The demographic data, clinical presentation symptom, sonographic feature and color or power Doppler f low in each type of the patients were documented. Histopathologically, the localized or diffuse form of GCTTS was also recorded.
The incidences of sonographic presentation in the superficial, encasing and juxta-fascial types of GCTTS were 46.7% (n=7), 33.3% (n=5) and 20.0% (n=3), respectively. The masses in the encasing type manifested with largest average size. The most common location of GCTTS in the superficial and encasing types was the hand. The 3 juxta-fascial type GCTTS were located in the subcutis of the hand and buttock, and the subfascial region of the forearm. On sonography, all GCTTS presented as hypoechoic masses with homogeneous or heterogeneous echogenicity. The tumors in the superficial and encasing types were eccentrically located to the related tendon and their superficial components were always disproportionally predominant. Bony erosion was found in three masses. No dermal attachment, decreased or increased sound through transmission, calcified or cystic component were noted in all masses. Only 26.7% of GCTTS demonstrated hypervascularity within the tumors. The two largest tumors were in encasing type and reported to be diffuse form microscopically. Two patients underwent recurrence, one with mass in superficial type and another in encasing type.
We concluded that extra-articular GCTTS typically appears as a hypoechoic mass with heterogeneous or homogeneous echogenicity and intimate contact with the abutting tendon or fascia. The diffuse form GCTTS should be considered if a characteristic mass presented with larger size, lobulated or irregular contour, complete encasement of the related tendon and hypervascularity. Besides, differential diagnosis of a well-defined and fascia-attached mass should include juxtafascial type GCTTS.