IntroductionBenign metastasizing leiomyoma (BML) is a rare disorder that affects women with a history of uterine leiomyoma, which is found to metastasise within extrauterine sites. The aetiology of BML remains unexplained. Because BML is rare, and most publications contain descriptions of single cases, no statistically determined time relations were found between the primary and secondary surgeries, which may have aetiological implications.ObjectivesTo determine age before BML surgery, age during diagnosis of BML, type of prior surgery, and location of metastasis based on the literature.MethodsA systematic review of four databases (Medline/PubMed, Embase, Web of Science, and Cochrane) covering articles published from 1 January 1965 to 10 April 2016. The inclusion criteria were full-text articles in English and articles containing case reports. Articles in languages other than English (39), articles containing incomplete data (14), i.e. no information regarding the time of surgery and/or the site of metastasis, articles bereft of case studies (25), and articles with access only to summaries, without access to the complete text (10) were excluded. Of 321 titles identified, only 126 articles met the aforementioned criteria.Results and conclusionsThe mean age during primary surgery and BML diagnosis was 38.5 years and 47.3 years, respectively. The most common surgery was total hysterectomy. The most frequent site of metastasis was the lungs; other organs were affected less frequently.The site of metastases and their number were not related to the longer time span between the patient’s initial surgery and occurrence of metastasis. The analysed data, such as the age during primary surgery, age during BML diagnosis, site and type of metastasis, do not provide us a clear answer. Thus, BML pathogenesis is most probably complex in nature and requires further multidirectional research.

Phyllodes tumors are rare breast neoplasms. Surgery is the treatment of choice. The role of postoperative radiotherapy and chemotherapy is still under dispute, as there are no equivocal prognostic factors. Treatment failure results in the occurrence of distant metastasis—mainly to the lungs, bones, liver, and brain. We have described the case of a woman with a malignant phyllodes tumor of the breast that was surgically treated. She did not receive adjuvant therapy because there is no consensus on the role of postoperative chemotherapy and radiotherapy. One year following the surgery, the patient had left-sided nephrectomy performed because of a rapidly growing tumor of the kidney. Renal cancer was suspected; however, a histopathological examination revealed that it was a metastatic phyllodes tumor. At the same time, the patient was diagnosed as having metastases in the other kidney, the lungs, liver, and bones.Our case report describes not only an unusual localization of the metastases (in the kidneys), but also failure of the chemotherapy and the aggressive course of malignant phyllodes tumor. Identification of patients with high risk for distant metastasis and the introduction of uniform rules for the management of adjuvant chemotherapy and radiotherapy would make planning treatment as efficacious as possible.