Two Case Reports of Intravenous Leiomyomatosis with Hyaluronan Expression

Abstract

Intravenous leiomyomatosis (IVL) is a rare benign neoplasm. Herein, we describe two cases of IVL at different levels of progression. The tumor in Case 1 was extensive, invading the right atrium after a hysterectomy for a uterine myoma. The tumor temporarily responded to hormonal treatment; however, tumor regrowth occurred. In contrast, the tumor in Case 2 extended only to the pelvic veins and was revealed preoperatively. Hysterectomy and bilateral salpingo-oophorectomy were performed, resulting in the complete surgical resection of the tumor. In Case 2, no recurrence has been observed. Tumor samples were evaluated for hyaluronan expression using Alcian blue staining (with and without hyaluronidase digestion). The tumor in Case 1 stained strongly positive for hyaluronan while the tumor in Case 2 stained weakly positive for hyaluronan. In contrast, a large non-IVL uterine leiomyoma (control) stained negative for hyaluronan. These results suggest a relationship between tumor hyaluronan expression and IVL progression, similar to that in other cancers.

Figure 1

(a) Large tumor occupying the abdominal cavity on a computerized tomography scan. (b) The histopathological diagnosis is leiomyoma (H&E 200×), based on the absence of nuclear atypia and a low mitotic index. (c) Tumor cells stained strongly positive for Alcian blue at a pH of 2.5 (200×). (d) Alcian blue staining disappears after hyaluronidase digestion (200×).

Figure 2

(a) Heterogeneous large tumor occupying the pelvic cavity on a computerized tomography scan. (b) Intravascular tumor within the dilated left internal iliac vein on a computerized tomography scan. (c) Multiple leiomyomas within the uterine corpus and cervix. (d) Tumor growth extending into the left ovarian vein.

Figure 3

(a) The intravenous tumor (H&E magnifying lens). (b) Vessel endothelium cells and vascular smooth muscle layer covered the intravenous leiomyoma (H&E 40×); an enlarged view of the area in Figure 3(a) is surrounded by a large black box. (c) Tumor cells stained strongly for positive Alcian blue at a pH of 2.5 (200×); an enlarged view of the area in Figure 3(a) is surrounded by a small black box. (d) Alcian blue staining disappears after hyaluronidase digestion (200×); the same area as that in Figure 3(c) is shown.