Iatrogenic parasitic myoma and iatrogenic adenomyoma after laparoscopic morcellation: A mini-review

Laparoscopy is widely recognized as a procedure of choice for gynaecological surgery. Myomectomy and hysterectomy are the most frequently performed surgical procedures in gynaecology. A morcellator is often used in myomectomies or subtotal hysterectomies, but morcellation may cause rare complications, such as parasitic iatrogenic myoma or adenomyoma. To improve patient counselling, proper risk estimation as well as risk factor identification should be acknowledged. This article aimed to review the literature on parasitic myoma and adenomyoma and to compare these diseases in terms of clinical, surgical, and prognostic factors. All published literature (case series and case reports) on iatrogenic myoma and adenomyoma was reviewed using PubMed/MEDLINE and ScienceDirect resources. Despite both conditions having an iatrogenic origin, iatrogenic parasitic myoma and adenomyoma are two different entities in terms of clinical manifestations as well as intraoperative particularities, with a common point: iatrogenic complication. A possible solution to avoid these iatrogenic complications is by using in-bag morcellation or switching to another surgical procedure (e.g., a vaginal or abdominal approach). It is concluded that parasitic myoma and iatrogenic adenomyoma are two different iatrogenic morcellator-related complications. In patients with a history of uterus or myoma morcellation who report pelvic symptoms, iatrogenic parasitic myoma or adenomyoma should be considered in the differential diagnosis.

Oestrogen-induced angiogenesis and implantation contribute to the development of parasitic myomas after laparoscopic morcellation

BACKGROUND

Iatrogenic parasitic myomas (PMs), caused by intra-corporeal power morcellation during laparoscopy is gradually increasing. However, the pathogenesis and medical treatment of PMs remain largely unelucidated.

METHODS

Laparoscopically-induced PM xenografted mouse model was conducted by xenografting human uterine myoma fragments into the abdominal cavity of SCID mice and hormonal manipulation was performed using this mouse model to demonstrate the role of oestrogen in the development of implanted PMs. Immunohistochemistry of oestrogen receptor α (ERα), progesterone receptor (PR), vimentin, vascular endothelial growth factor (VEGF), microvessel density (MVD) and Ki-67 index was performed and compared.

RESULTS

In the patient with PMs, ERα, PR, angiogenesis and proliferative property expression were upregulated in PM lesions compared to uterine myomas. In the laparoscopically-induced PM mouse model, implanted myomas had more steroid receptor expressions, angiogenesis and proliferative property compared with pre-xenografted or non-implanted myoma. Depletion of oestrogen in the ovariectomized (OVX) mice decreased laparoscopically-induced PM implantations. In comparison, the implantations of PMs were increased with additional E2 supplement. Hormonal manipulation in the PM mouse model, including AI, GnRHa and SERM groups, were compared and AI significantly decreased the implantations, steroid receptor, angiogenesis, cell density, and proliferative index of PMs compared with control group. Furthermore, GnRHa significantly decreased VEGF and MVD expressions compared with control group.

CONCLUSIONS

These data highlight the crucial role of oestrogen in the development of laparoscopically-induced PMs and suggest that hormone manipulation may be a potential therapeutic agent.

TRIAL REGISTRATION

This protocol was approved by the Human and Animal Institutional Review Board of Taipei Veterans General Hospital ( VGHIRB No 2014-10-002C on Nov. 17^th, 2014; IACUC 2014-119 on Aug. 22^nd, 2014).

Parasitic leiomyomas: a systematic review

BACKGROUND

Parasitic leiomyomas were first described as early as 1909 but are a rare condition. In recent years, due to the rise of laparoscopic surgery and power morcellation, several cases of parasitic leiomyomas associated with this surgical procedure have been reported.

METHODS

A literature search was performed using PubMed, Embase and Google Scholar with the following combination of keywords: leiomyoma OR uterine neoplasms OR uterine myomectomy OR laparoscopy OR hysterectomy OR peritoneal neoplasms AND parasitic. Papers describing parasitic leiomyomas were included. The results of these studies are summarized herein.

RESULTS

We retrieved abstracts of 756 papers. Of these, 591 were excluded for not fulfilling the inclusion criteria and 54 were removed as duplicates; after full-text assessment, 8 were rejected for presenting cases of malignancy and finally 103 were included in our systematic review. From these, we present information about 274 patients with parasitic leiomyomas. The mean age of women was 40 years (range 18-79 years); and 154 (56%) had no history of uterine surgery, the others (120, 44%) having had a previous myomectomy or hysterectomy. Of the total, 106 (39%) women had a history of power morcellation. The most frequent clinical symptom was abdominal pain (49%) and the most frequent presentation was disseminated peritoneal leiomyomatosis.

CONCLUSIONS

While parasitic leiomyoma was first described a century ago, the recent introduction of laparoscopic power morcellation has increased the number of reported cases.

A Retrospective Analysis of the Impact of Myomectomy on Survival in Uterine Sarcoma

Laparoscopic myomectomy is a minimally invasive, conservative surgical approach commonly used for the treatment of uterine fibroids. However, there is a lack of effective means to distinguish the nature of uterine tumors prior to surgery. The impact of fibroid morcellation during laparoscopic surgery on the dissemination of cancerous uterine fibroids and long-term survival of patients has gained increasing attention. A retrospective cohort study was conducted to analyze the impact of different surgical approaches on recurrence-free survival (RFS) and overall survival (OS) in patients with a postoperative pathological diagnosis of uterine sarcoma at a single medical center. Patients who underwent the first surgery for uterine fibroids (confined to the uterus) and had a postoperative pathological diagnosis of uterine sarcoma were selected in the Chinese PLA General Hospital from January 2005 to January 2014. Based on the use of fibroid morcellation, the subjects were divided into fibroid morcellation (FM) and total hysterectomy (TH, non-morcellation) groups. Follow-up outcomes, including RFS and OS times, were observed. In total, 59 patients were included, with 30 cases in the FM group and 29 cases in the TH group. There were no significant differences in RFS and OS time between the two groups (RFS: P = 0.16, OS: P = 0.09). Multivariate correlation analysis showed that the impact of a higher grade level on RFS and OS was nearly 2-fold the impact of a lower grade level (RFS: P = 0.04, odds ratio (OR) = 1.97; OS: P = 0.03, OR = 2.29). Intraoperative morcellation, postoperative adjuvant therapy, age, tumor size, FIGO stage, and surgical approach were not risk factors affecting RFS and OS. Fibroid morcellation during laparoscopic surgery (including laparoscopic, transvaginal and transabdominal approaches) had no significant impact on RFS and OS time in patients. However, the 5-year RFS and OS rates were both lower in the FM group than in the TH group. Grade level was a significant risk factor for the prognosis of patients with uterine sarcoma.

Power morcellators: a review of current practice and assessment of risk

Power morcellation has come under scrutiny because of a highly publicized case of disseminated leiomyosarcoma following a laparoscopic hysterectomy. A recent Federal and Drug Administration safety communication discouraging use of power morcellators on presumed uterine leiomyoma further highlights the need for reexamination of uterine tissue extraction. This clinical opinion aims to summarize current approaches to uterine/fibroid tissue extraction including the associated immediate and long-term potential risks of open power morcellation. The known data about risk of uterine sarcoma is reviewed followed by a discussion of acceptable risk and informed consent in the context of shared-decision making.

Is fibroid heterogeneity a significant issue for clinicians and researchers?

The clinical and scientific literature overwhelmingly deals with fibroids as a single entity or disease. This convenient assumption of homogeneity may be an important oversight given that substantial evidence exists for heterogeneity between fibroids at many levels. Failure to recognize and accommodate fibroid heterogeneity can have significant ramifications for both clinical treatment decisions and research protocol design. The aim of this article is to review the current knowledge of fibroid heterogeneity and to identify key areas where fibroid heterogeneity should be taken into consideration both clinically and when designing research protocols. Uterine leiomyomata display significant and well-documented heterogeneity in symptoms, diagnostic imaging appearance, pathology, genetic background and therapeutic requirements. Additional research is needed to better understand fibroid heterogeneity as it relates to pathogenesis, molecular targets for potential new therapies, patient symptoms and, ultimately, treatment. To this list should also be added heterogeneity of genetics, lifestyle and individual clinical characteristics of the fibroid. Increasingly, an understanding of uterine leiomyoma heterogeneity will be of importance for clinicians who see patients with this common and costly disease.