Year: 2017
Type: article
Study design: Case Report
Abstract: Metastasis to the uterus occurs very rarely, accounting for less than 10% of all cases of metastasis involving the female genital tract; mammary and gastrointestinal carcinomas are the most frequent extragenital primary neoplasms metastasizing to the uterine corpus1. Few data on such tumors are available in the literature, though Kondo et al.2 reported on 24 cases of breast cancer metastasized to uterine leiomyoma, followed up at surgery (n = 16) and on autopsy (n = 8). Preoperative diagnosis of breast cancer metastatic to a leiomyoma is challenging and, to the best of our knowledge, no data have been reported in the literature regarding its ultrasound appearance. Indeed, the few reports on imaging features of uterine leiomyoma with metastasis from breast cancer have been on those obtained using computed tomography (CT) scan or magnetic resonance imaging2, 3. There seems to be only one description of ultrasound findings for a uterine leiomyoma shown to contain metastatic cells from a previously diagnosed breast cancer4. However, the ultrasound features were not specific and failed to suggest malignant disease, while a positron emission CT (PET-CT) scan was necessary to make the correct preoperative diagnosis, as it revealed intense uptake in the uterine area4. The current report provides more detailed characterization of ultrasound features in isolated involvement of a uterine leiomyoma in a patient diagnosed previously with ductal breast cancer. The patient was a 67-year-old woman with a previous poorly differentiated left invasive ductal breast carcinoma (pT1c, N1ii, M0), diagnosed in 2002. She received adjuvant chemotherapy, radiotherapy, and tamoxifen for 5 years. Standard follow-up examinations, including mammography, ultrasonography of the breast, bone scintillation scanning and CT, were uneventful for 10 years. From October 2011 until February 2012, a progressive increase in CA15-3 serum levels up to 60 IU/mL was documented. The patient was asymptomatic and the work-up evaluation, including chest x-ray, mammography, ultrasonography of the breast and bone scan, showed no pathological findings. The patient had been referred due to a uterine leiomyoma that had been diagnosed 15 years before, which had been followed regularly with bi-/annual ultrasound examinations. An ultrasound examination had been performed 6 months before the increase in CA15-3, with findings comparable to those of the previous examinations: a myoma with diameter of 10 cm, located at the posterior wall of the uterus, with unremarkable echotexture and vascularization characteristics. It was not until November 2011 that the last pelvic ultrasound scan showed a hypoechoic intrauterine mass (maximum diameter, 10 cm) with cystic areas. In February 2012, CT scan confirmed an enlarging 10–13-cm pelvic mass that was predominantly solid with areas of cystic degeneration, and the patient was referred to our institution. On ultrasound examination, the uterus appeared enlarged with subverted echostructure due to the presence of an intrauterine solid mass of about 11 cm in diameter with large cystic areas with irregular internal margins and no shadow stripes. On color Doppler evaluation, the lesion showed moderate vascularization (Figure 1). The scan findings were suggestive of uterine leiomyoma with areas of cystic degeneration, although an atypical smooth-muscle tumor or a leiomyosarcoma could not be excluded. Surgery was planned with no additional imaging examination. Total abdominal hysterectomy with bilateral salpingo-oophorectomy was performed. At the time of laparotomy, the uterus was deformed by an intramural mass of 10 cm in diameter; the uterine serosa and the ovaries were normal. There was no evidence of ascites or peritoneal tumor deposits. The cut surface of the uterus resembled a leiomyoma, but scattered areas of hemorrhage were found more frequently than would be expected in a common leiomyoma. On immunohistochemical staining, cells were positive for GCDFP-15, estrogen and progesterone receptors, p53, and AE1 and AE3 cytokeratins, and negative for vimentin, MUC2, MUC5, and CK20. The original slides of the breast tumor were reviewed and demonstrated that the primary breast carcinoma had morphology similar to that of the malignant cells in the myometrial lesion. Postoperative tumor marker (CA15-3) level returned to within normal range. A postoperative PET-CT scan was negative for other metastatic foci. No adjuvant chemotherapy was administered. Hormone therapy with letrozole was started. After 30 months from surgery, the patient was alive with no signs of recurrence. This case is noteworthy because it reveals an unusual uterine intraleiomyoma breast metastasis 10 years after the primary cancer diagnosis, and shows the role of pelvic ultrasound examination in the metastatic work-up of breast cancer. Modifications of myometrial masses detected on ultrasound represent a challenge for clinicians, since they could raise the suspicion of malignancy in the presence of rich vascularization and irregular cystic areas, even though there are only few, and no definitive, data on these lesions in the literature. In particular, the eight leiomyosarcomas included in a series by Exacoustos et al.5 were significantly larger compared with other benign uterine tumors (leiomyomas, cellular leiomyomas, smooth-muscle tumors of uncertain malignant potential), and showed more frequently degenerative cystic change and marked increase in central and peripheral vascularity. The present case suggests the possibility of including intraleiomyoma metastasis originating from a breast cancer in the differential diagnosis of such uterine masses. In conclusion, this experience confirms the role of pelvic ultrasound examination as an important part of follow-up investigations for women with primary breast cancer, specifically in the presence of progressively increasing levels of CA15-3 despite a lack of symptoms and apparent absence of suspected lesions in regions more likely to be affected by metastatic breast cancer.
DOI: 10.1002/uog.18903
Language: English
Subfield: Obstetrics and Gynecology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2755513826