Long-term effect of letrozole on metastatic uterine smooth muscle tumors of uncertain malignant potential: A case report.

A 48-year-old woman underwent total abdominal hysterectomy and right salpingo-oophorectomy and was initially diagnosed with a uterine leiomyoma and right ovarian cystadenoma. After 4 years, multiple pulmonary metastases were identified, and treatment with gonadotropin-releasing hormone agonists was started, but stopped later due to disease progression. The patient developed dyspnea and underwent right upper lobectomy. The histopathological findings were consistent with those of pulmonary metastases secondary to a uterine smooth muscle tumor of uncertain malignant potential. Slow disease progression after a poor response to adriamycin and hormone receptor positivity led to the start of letrozole. Letrozole induced spontaneous regression of the pulmonary metastases, and about 2 years into the treatment, sustained response was achieved with minimal side effects. This may be the first case supporting the long-term efficacy and safety of letrozole in the management of adriamycin-resistant lung metastases of uterine smooth muscle tumors of uncertain malignant potential.

Antiretroviral therapy achieved metabolic complete remission of hepatic AIDS related Epstein-Barr virus-associated smooth muscle tumor.

Epstein-Barr virus-associated smooth muscle tumor (EBV-SMT) is a rare mesenchymal tumor which occurs in immunocompromised patients. The immune status is an important factor in the treatment of EBV-SMTs, but the efficacy of antiretroviral therapy (ART) is not elucidated in acquired immune deficiency syndrome (AIDS) related EBV-SMTs. Here, we report the first successful case of a 29-year-old man with hepatic AIDS related EBV-SMT treated with ART solely. Positron emission tomography scan was useful for the evaluation of disease status. Recent advances in ART that enables to restore patient's immune status rapidly may change the treatment strategy in AIDS related EBV-SMT.

PD-L1 Expression and Tumor-infiltrating Lymphocytes in Uterine Smooth Muscle Tumors: Implications for Immunotherapy.

Immunotherapies targeting the PD-1/PD-L1 checkpoint axis are of growing interest for the treatment of mesenchymal neoplasms. However, PD-L1 expression and tumor-associated lymphocytes have not been well-investigated in uterine smooth muscle tumors. Forty-nine uterine smooth muscle tumors (23 leiomyosarcomas, 8 smooth muscle tumors of uncertain malignant potential [STUMP], 7 atypical leiomyomas, and 11 benign leiomyomas) were evaluated for tumoral and tumor-associated immune PD-L1 expression and tumor-associated T-cell infiltration. ALK immunohistochemistry was performed to exclude inflammatory myofibroblastic tumors. Tumor PD-L1 expression was seen in 70% of leiomyosarcomas and 14% of atypical leiomyomas; no cases of STUMP or benign leiomyoma demonstrated tumoral PD-L1. PD-L1 positivity was seen in tumor-associated immune cells in 78% of leiomyosarcomas, 25% of STUMP, no cases of atypical leiomyomas, and 9% of benign leiomyomas. Of the 23 leiomyosarcomas, 15 (65%) had a combined positive score ≥1, while of the 26 other uterine smooth muscle tumors, only 2 (8%) had a combined positive score ≥1. Tumor-associated CD8+ cells were highest among leiomyosarcomas (mean: 87/high-power fields vs. 17/high-power fields for nonleiomyosarcomas), and were significantly associated with PD-L1 expression. One PD-L1, CD8-enriched leiomyosarcoma showed an ALK overexpression suggesting possible classification as inflammatory myofibroblastic tumor, but otherwise lacked morphologic features of this entity. Leiomyosarcomas demonstrate significantly higher PD-L1 expression and cytotoxic T-cell infiltration when compared with other uterine smooth muscle tumors. These data suggest the possibility that treatment with targeted immunotherapy may be appropriate in a selected population of patients with leiomyosarcoma and, potentially, in related tumors bearing ALK rearrangements.

Treatment response with sirolimus for a pediatric patient with an EBV-associated smooth-muscle tumor after bone marrow transplantation.

Epstein-Barr virus-associated smooth-muscle tumors (EBV-SMTs) are unique and rare neoplasms described in immunocompromised patients. The case describes a nine-year-old female with a history of acute lymphoblastic leukemia with relapse and subsequent allogeneic bone marrow transplantation who presented with multiple EBV-SMTs of the liver. EBV utilizes the mammalian target of rapamycin (mTOR) pathway for tumor growth, and sirolimus, a mTOR inhibitor, has shown to result in a short-term response. We now report an extended treatment response with sirolimus in a pediatric patient with an EBV-SMT.

Epstein-Barr virus-associated smooth muscle tumors after kidney transplantation: treatment and outcomes in a single center.

BACKGROUND: Epstein-Barr virus-associated smooth muscle tumors (EBV SMT) in adult kidney transplant recipients (KTR) are rare. The aims of this study are to document the clinical features, types of treatment given, and outcomes of KTR with EBV SMT in our institution. METHODS: Sixteen patients were identified from our institution's databases. Patients' survival, tumor outcome, and graft survival were compared between patients who remained on cyclosporine-based immunosuppressant and those who converted to sirolimus-based therapy. RESULTS: The median time of diagnosis was 9.4 yr after kidney transplantation, and majority of the patients had multifocal disease at the time of diagnosis. Overall, the patient survival rate was 75% over a mean follow-up period of five yr. Two patients with non-functioning allograft at the time of diagnosis of EBV SMT were excluded from the treatment outcome analysis. Comparing the sirolimus (n = 7) vs. cyclosporine groups (n = 7), patient survival rate was 100% vs. 42.9% (p = 0.08), graft survival 71.4% vs. 28.7% (p = 0.53), and disease-free status 42.9% vs. 14.3% (p = 0.73), respectively. CONCLUSION: Surgical resection in combination with decreasing immunosuppression or conversion to sirolimus appears to be effective in the treatment of EBV SMT in KTR.

Smooth muscle tumour of the right groin: description of a unique case.

INTRODUCTION: A deep soft tissue smooth muscle tumour is a rare entity with few cases described in the literature. MATERIALS AND METHODS: Herein, we report a case of a smooth muscle tumour of the right inguinal area which presented as a painful mass. This case is unique because of the anatomic location of the tumour, which has not been reported before, and the clinical presentation of this tumour mimicked a hernia. CONCLUSION: Smooth muscle tumours in the inguinal area are an exceptionally rare occurrence, but clinicians should always consider less routine causes for a painful inguinal mass.

Pathologic considerations of uterine smooth muscle tumors.

Smooth muscle tumors are the most common type of uterine neoplasm. The vast majority of such tumors are benign leiomyomas. Leiomyosarcomas fortunately are relatively infrequent. A variety of gross and microscopic features may be found in both benign and malignant tumors and great care must be taken not to mistake leiomyomas with atypical or unusual features of leiomyosarcomas. Individual features, such as hypercellularity, necrosis, nuclear atypia, mitotic figures, and intravascular growth, are ominous but must be interpreted with caution because variants of benign leiomyoma may contain such changes.