An unusual case of intravenous leiomyomatosis involving the right atrium.

To the Editor: A 48-year-old Chinese woman complained the chest distress, shortness of breath and amaurosis fugax for 3 months. The above clinical symptoms worsened gradually 1 week ago. The diastolic rumbling murmur was heard on the third and fourth intercostal space of the left sternum during a physical examination, when the patient was sitting down. The patient's vital signs were stable. A laboratory test revealed normal.

Cardiac ultrasound (GE VIVID E9 Color Doppler Ultrasonic Diagnosis Apparatus, USA) revealed a neoplasm in the inferior vena cava and right atrium. The mass in right atrium was measured as 78 × 38 mm [Figure 1A]. Gynecologic ultrasonography (Siemens ACUSON S2000, Germany) manifested a cyst-solid mass with the size of 132 × 131 × 98 mm in the pelvic cavity [Figure 1B]. Magnetic resonance imaging (Siemens Skyra 3.0 T scanner, Germany) showed that the soft tissue signal was present in the vena iliaca interna and vena iliaca externa, right common iliac vein, and inferior vena cava, extending into the right atrium. In addition, a huge soft tissue mass was located in the pelvic cavity [Figure 1C and 1D].

Figure 1

Representative image of the patient. (A) Ultrasonography shows that the mass measured 78 mm × 38 mm in right atrium moves back and forth between the right atrium and the right ventricle through the tricuspid orifice with the heartbeat. (B) Gynecologic ultrasonography reveals cyst-solid mass with the size of 132 mm × 131 mm × 98 mm in the pelvic cavity. (C and D) Magnetic resonance imaging display soft tissue signal in the pelvic cavity extending into the right atrium from the right common iliac vein, and inferior vena cava. (E) The surface of the tumor is negative for CKP (Immunohistochemical staining, magnification, ×100). (F–I) The tumor cells are positive for Desmin, vimentin, SMA and CD31, respectively (Immunohistochemical staining, magnification, ×100). (J and K) The lesions around the tumor are positive for CD68, while the endothelium of the vessels is positive for CD34 (Immunohistochemical staining, magnification, ×100). (L) Histological image reveals spindle cells arranged in fascicles without cytologic atypia (hematoxylin and eosin,magnification, ×100). CKP: Cytokeratin pan; SMA: Smooth muscle actin.

The patient was submitted to 2-stage operations. Cardiac and vascular surgery as the first-stage procedure was performed under general anesthetic and with extracorporeal circulation. A mass of 6 cm × 6 cm × 3 cm was resected from the right atrial. The histological images (hematoxylin and eosin) revealed fusiform smooth muscle cells arranged in a bundle and vascular hyaline degeneration in the tumor. Immunohistochemical staining (DAKO or Abcam, Hong Kong, China) displayed S-100 (-), cytokeratin pan (CKP) (-), Desmin (+), vimentin (1+), smooth muscle actin (SMA) (2+), CD31 (1+), CD68 (+), CD34 (vascular endothelium+), myoD1 (-), and ki67 (<10%), respectively. Morphology and immunohistochemistry supported angioleiomyoma [Figure 1E–1K]. In the second-stage operation, the patient underwent panhysterectomy, bilateral salpingo-oophorectomy, and myomectomy of inferior vena cava. Two 30-cm long masses were removed from inferior vena cava. Pathological examination showed the spindle-shaped tumor cells were arranged in a knit-like and bunch-like formation, and exhibited rare mitotic figures [Figure 1L]. Immunohistochemical staining displayed D2–40 (endothelial cells of tumor location [-]), estrogen receptor (ER) (75%), progesterone receptor (PR) (75%), ki67 (5%), SMA (3+), Desmin (3+), CD34 (vascular endothelium+), vimentin (1+), p53 (-), CD31 (vascular endothelium+), Factor VIII (vascular endothelium+), and S-100 (-), respectively. The diagnosis was intravenous leiomyomatosis (IVL). No recurrence of the tumor was observed during the follow-up for 9 months.

IVL occurs in female subjects aged 33 to 54 years (average age, 44 years). Those patients usually had a history of uterine fibroids or hysterectomy.[ The clinical characteristics of IVL depend on the scale and location of liomyoma. The patients with IVL usually lack typical clinical symptoms, and early diagnosis was difficult. The pathogenesis of IVL remains unclear until now. Mainly there are 2 etiological theories about the origin of IVL. In most cases, IVL was assumed to arise from the local extension of myometrial smooth muscle cells into adjacent venous channels of the pelvic cavity. Less commonly, IVL was believed to derive from smooth muscle in the vessel wall.[ In addition, Kir et al[ reported the patient of IVL with high levels of estradiol and estrogen receptor. However, the endothelial cells and subendothelial cells in the vessel wall had little estrogen receptor or progesterone receptor expression. The recent studies also suggested normal myometrium and IVL were strongly positive for desmin, while the smooth muscle cells in the vascular wall did not express the feature of desmin.[ More evidence supports the origin of IVL from myometrial smooth muscle cells, which may be an explanation why IVL and uterine fibroids are mostly concomitant. The recurrence rate of IVL was 30%, surgery still was the preferred option for its treatment.[ Hormonal therapy was also used in the past decade. However, the efficacy of antiestrogenic drugs, such as tamoxifen and gonadotrophin-releasing hormone agonist (GnRHa), has yet to be established.[

In conclusion, IVL as a rare disease, early detection, and timely treatment is necessary for it. Once the imaging presents the mass of uterine or periuterine, and extensive intravenous extension, IVL must be considered. Following the discovery, surgery will be initiated. Therapeutic process warrants a close cooperation of the multidisciplinary team. Given the high recurrence of this disease, close long-term follow-up is also critical.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that her name and initial will not be published and due efforts will be made to conceal her identity, but anonymity cannot be guaranteed.

Conflicts of interest

None.