DOI: 10.5061/dryad.9ghx3ffm7
title: A critical review of uterine leiomyoma with subsequent recurrence or metastasis: A multicenter study of 62 cases

description: Aim: Histopathologic diagnosis of a subset of uterine smooth muscle tumors
 is challenging. We report a critical review regarding the
 clinicopathological point of view of 62 cases of subsequently recurred or
 metastasized leiomyoma. Methods: Medical records and glass slides of 62
 cases of uterine smooth muscle tumor diagnosed as leiomyoma, which
 subsequently recurred or metastasized, were critically reviewed by
 pathologists specializing in gynecologic pathology and oncology. 
 Results: In 47 (75.8%) of 62 cases, the diagnosis of leiomyoma was
 confirmed, including 11 intravascular leiomyomatosis (IVL) and benign
 metastasizing leiomyoma (BML). In 29 cases (46.8%) laparoscopic surgery
 was performed, of which morcellator without a bag was employed in 23
 cases. Fifteen cases (24.2%) appeared to be underestimated and were
 re-classified as smooth muscle tumor of uncertain malignant potential
 (STUMP), leiomyosarcoma, or other malignant mesenchymal tumors.
 Recurrences in 7 cases (11.3%) were interpreted to be a malignant
 transformation, and one Smooth muscle tumor of uncertain malignant
 potential (STUMP) recurred as STUMP.  Conclusion: The recurrence
 or metastasis in cases of “leiomyoma” is attributed to iatrogenic or
 under-evaluation of primary tumors, although a subset of cases is a rare
 example of biological progression.
description: This study was conducted with
 approval from the Institutional Review Board of Kurume University (number
 15264). Assessed cases handled by 430 facilities registered with the Tumor
 Committee of the Japan Society of Obstetrics and Gynecology in which a
 uterine myoma diagnosed and treated between 2004 and 2013 subsequently
 showed clinical recurrence or metastasis. We performed a questionnaire for 430 facilities
 asking them to participate in the study. Of these facilities, 276 gave us
 answers to participate, and 30 out of 276 matched our study
 design. Regarding the
 definition of recurrence, although it is difficult to distinguish between
 recurrent and newly fibroids, according to the previously published
 article, recurrent myoma was defined as a myoma with a diameter of
 &gt; 1cm. Pre-existent uterine and extrauterine myomas detected by MRI
 and/or ultrasonography excluded. All the primary myoma confirmed
 pathological diagnoses of leiomyomas and cases with suspicion of
 malignancy prior to surgery or with the postoperative diagnosis of
 malignancy were also excluded. A survey was conducted at the targeted
 facilities, and clinical information was collected from 62 cases handled
 by 30 facilities that agreed to participate in the survey. The contents of
 the survey included the following: patient age at the time of initial
 surgery, pregnancy and childbirth history, with or without magnetic
 resonance imaging (MRI) examinations, the procedure performed in the
 initial surgery, history of procedures using a morcellator (and bag),
 macroscopic findings at the time of the initial surgery, number of
 sectioned slides, pathological diagnosis, recurrence interval, the form of
 recurrence, details of the treatment administered at the time of
 recurrence, and patient status. Central pathology review was conducted
 using a multi-head microscope by four pathologists specializing in
 gynecological pathology (SS, HY, YM, and YO) and a consensus diagnosis was
 made. Of these, the primary lesions were also evaluated in 33 cases. The
 Stanford criteria established by Bell et al. were used to determine the malignancy of
 uterine smooth muscle tumors. According to the Stanford criteria, the
 presence of any two of the three following findings warrants a diagnosis
 of leiomyosarcoma: moderate to severe cytological atypia, coagulative
 tumor cell necrosis, and mitotic activity higher than 10 mf/10
 HPFs. Subtypes of
 leiomyoma were classified according to WHO classification (4th
 edition).
description: Excel file, JPEG and TIF files.