腹外纖維瘤病之磁振造影表現

Magnetic Resonance Imaging of Extraabdominal Fibromatosis

本研究回溯性地收集17位病人輕手術病理證實的21個腹外纖維瘤病病灶（10個原發腫瘤、11個復發病灶），評估其在磁振造影不同脈衝序列下之影像表現。分析結果如下：半數(50%)的原發腫瘤及所有(100%)的復發病灶都呈現浸潤性邊緣。與鄰近的肌肉組織相比較：在T1影像上，所有(100%)的病灶都呈現均勻或不均勻之中等或高訊號強度；在T2/T2*影像上，大多數(90%)的病灶呈現均勻或不均勻之明顯顯影。在所有的脈衝序列影像上，大多數(86%)的病灶內都出現低訊號之纖維點線。所有(100%)的病灶周圍都未出現組織水腫。原發腫瘤和復發病灶都可以取代或推移相鄰的肌肉組織，兩者之間並無顯著的差異。少數(19%)的病灶會包圍血管神經束，而只有1例(9%)復發病灶會侵犯相鄰的骨骼。腹外纖維瘤病是一良性但局部侵犯性的腫瘤，具有多樣化之磁振造影表徵；然而，在T1影像上呈中高訊號強度，在T2/T2*影像上呈高訊號的病灶內出現低訊號之纖維點線，以及在靜脈注射顯影劑後伴隨脂肪抑制之T1影像上呈明顯顯影的類型，則有助於纖維瘤病之鑑別診斷。

The purpose of this study is to define the magnetic resonance(MR)imaging characteristics of extraabdominal fibromatosis. We retrospectively evaluated the MR images of 21 lesions (10 primary tumors and 11 recurrent ones)of histopathologically proven fibromatoses in 17 patients. Half the primary tumors and all the recurrent ones demonstrated infiltrating margins. Most lesions showed homogeneous or heterogeneous intermediate to high signal intensity (SI) on T1-weighted images (T1WI), homogeneous or heterogeneous high SI on T2/T2*-weighted images (T2/T2*WI), homogeneous or heterogeneous marked enhancement on post-contrast T1WI with fat suppression, and linear and/or dot-like fibrotic low-signal areas on all pulse sequences. None of the lesions had surrounding edema. While tumor involvement, either replacement or displacement, of the adjacent muscle was evident, no significant differences were noted between the primary and recurrent tumors. Few lesions showed neurovascular encasement or bone involvement. In conclusion, extraabdominal found in malignant tumors. However, the presence of intermediate to high SI on T1WI,lineaar and/or dot-like fibrotic low-signal areas with in the high-signal lesions on T2/T2*WI, and marked enhancement on post-contrast t1WI with fat suppression can narrow the differential diagnosis of fibromatoses.