Endometrial polyps refer to overgrowths of endometrial glands and stroma within the uterine cavity. Endometrial polyps vary in size from few millimeters to several centimeters in diameter. Polyps may be found as a single lesion or multiple lesions filling the entire endometrial cavity. Endometrial polyps may be diagnosed at all ages; however, peak incidence occurs between the age of 40 to 49 years old. Although these polyps are considered benign, there is a small risk of malignant transformation.
Endometrial polyps are localized overgrowths of the endometrial glands and stroma that protrudes out of the endometrium. The definite etiology of endometrial polyps is unknown. However, endometrial polyps are associated with endometrial hyperplasia; therefore, unopposed estrogen is considered to be a risk factor. Other mechanisms that have been associated with the development of polyps include increased endometrial aromatase activity, TGF-beta, VEGF, BCL-2, and genetic factors. Endometrial abnormalities, including the development of polyps, are associated with chronic tamoxifen therapy and occurs in 20% to 35% of females.
A majority of polyps are benign; however, malignant transformation can occur in 0 to 13%. Malignancy in an endometrial polyp is related to a patient’s age and menopausal status. The prevalence of malignant endometrial polyps in the symptomatic postmenopausal female is 4.47% compared with 1.51% in an asymptomatic postmenopausal female. Additional risk factors for malignant endometrial polyps include age greater than 60, large-sized polyps, menopause status, symptomatic bleeding, and polycystic ovarian syndrome.
Endometrial polyps occur in all age groups, with a peak incidence between the age of 40 to 49. The prevalence of endometrial polyp in reproductive-aged women with abnormal uterine bleeding is estimated between 20 to 40 percent. Endometrial polyps are found in approximately 10 percent of women at the time of autopsy. Premenopausal females are less likely to have malignant endometrial polyps compared to postmenopausal females.
Polyps are endometrial epithelial proliferations comprised of vascular, glandular, fibromuscular, and connective tissues. Endometrial polyps are primarily covered by epithelial tissue superficially and contain a largely vascular core. Polyps may be classified as sessile, pedunculated, or prolapsing. A prolapsed polyp may contain areas of squamous metaplasia, infection or ulceration. A majority of polyps will be composed of the endometrium that differs from the surrounding endometrium and does not respond to cyclic hormonal changes. Other histological findings include carcinomatous, atrophic, or hyperplastic.
Patients with endometrial polyps may be asymptomatic, or the most common symptom is abnormal uterine bleeding. Other associated symptoms include abdominal pain, pelvic pain, or infertility. One in four reproductive-aged women with abnormal bleeding will have endometrial polyps within the cavity. For any patient with abnormal uterine bleeding, it is important to identify the underlying cause, severity, any associated symptoms, and comorbidities. Obtaining a comprehensive medical and surgical history is crucial to exclude other causes of abnormal uterine bleeding. Although, there is not a diagnostic bleeding pattern for endometrial polyps, a detailed history of the patient’s bleeding pattern should be obtained. The most commonly reported patterns include menorrhagia and intermenstrual spotting.
Tamoxifen, often used in the treatment of breast cancer, has agonistic or antagonistic effects on tissue containing estrogen receptors. Tamoxifen works as an anti-cancer agent on breast tissue; however, it acts as a carcinogenic agent on endometrial tissue. Chronic tamoxifen use has been associated with the development of endometrial polyps, with an incidence of 20% to 35%. Furthermore, hormone replacement therapy for menopausal symptoms may also be associated with the formation of endometrial polyps with reported symptoms of irregular bleeding and thickened endometrium on ultrasound.
A general physical exam should be performed along with a bimanual exam and sterile speculum exam during the clinic visits. The cervix and vaginal vault should be fully examined to rule out other structural causes for the patient’s symptoms. A pedunculated endometrial polyp may be visualized from the external os.
Transvaginal ultrasound is the most common and efficient technique in imaging pelvic structures. Findings on ultrasound may appear nonspecific with diffuse or localized, echogenic endometrial thickening. In patients with symptoms of postmenopausal bleeding, endometrial thickness of less than 4 mm is associated with an atrophic endometrium. However, increased endometrial thickness greater than 4 mm is related to endometrial pathology, including polyps. The location of the polyp, number, and diameter does not correlate with the reported symptoms.
Another method to evaluate the endometrial cavity is with saline-infusion sonography (SIS). This modality involves instilling about 5 to 30 mL of warmed saline into the uterine cavity using a thin catheter during the proliferative phase of the menstrual cycle. Polyps are better visualized with fluid outlining the mass. Contraindications include active uterine or cervical infection and pregnancy. SIS provides a better evaluation of the adnexa and cornua compared to transvaginal ultrasound. In addition, SIS provides better differentiation between submucosal fibroids and endometrial polyps by visualizing the location in relation to the endometrial layer. A polyp will be seen arising from the endometrial layer, and a submucosal fibroid will be visualized under this layer. Other methods of evaluation include hysterosalpingograms or hysteroscopy.
More importantly, these methods will not provide tissue diagnosis. Tissue sampling should be considered due to the risk of malignancy associated with endometrial polyps. To obtain tissue diagnosis, an endometrial biopsy, dilation, and curettage (D&C) or hysteroscopic polypectomy must be completed. Blind tissue sampling with endometrial biopsy or D&C is inaccurate in the diagnosis of endometrial polyps and should only be used in settings where hysteroscopic treatment is unavailable.
Laboratory studies are also considered in the evaluation of abnormal uterine bleeding. Studies should include a urine pregnancy test, a complete blood count, and a coagulation panel to rule out anemia and coagulopathy.
For asymptomatic and low-risk patients, endometrial polyps can be managed conservatively with observation. Incidental endometrial polyps may regress spontaneously if left untreated. In one trial, 29% of endometrial polyps resolved spontaneously after 1 year in premenopausal patients. Conservative management includes periodic assessment of polyp growth with ultrasound. Medical management with hormonal therapy has limited support in the literature and cannot be recommended at this time.
Hysteroscopic polypectomy is considered the standard treatment of an endometrial polyp. Polyps may be associated with underlying endometrial pathology; therefore, both the polyp and the surrounding endometrium should be histologically evaluated. Benign polyps have been found in 20% of cases with a diagnosis of endometrial carcinoma. The timing of hysteroscopic polypectomy is unclear for asymptomatic and low-risk patients. A retrospective study performed to determine the appropriate timing of polypectomy found no incidence malignancy on histologic specimens and concluded that it is unclear when to perform routine polypectomy in asymptomatic females. Larger sized polyps measuring greater than 1.5 cm in length is less likely to resolve spontaneously, and polypectomy could be considered in symptomatic patients.
Hysterectomy is a radical surgical option that eliminates the risk of polyp recurrence and the potential for malignancy. Hysterectomy is associated with significantly greater risk to the patient and cost and should only be contemplated after extensive patient counseling.
For patients with anemia secondary to abnormal uterine bleeding, consider daily iron supplementation.
The differential diagnosis includes submucosal leiomyoma, adenomyoma, retained products of conception, endometrial hyperplasia, endometrial carcinoma, and uterine sarcomas.
After hysteroscopic polypectomy, significant improvement in intermenstrual bleeding has been reported. Treatment after hysteroscopic polypectomy is effective with low recurrence in patients who initially presented with fewer number of polyps. The recurrence rate in histologically confirmed polyps is approximately 2.5% to 3.7%. Recurrence rates are further decreased if hysteroscopic polypectomy is combined with endometrial ablation or insertion of a levonorgestrel-releasing intrauterine device. However, there is limited data to support these recommendations, and currently, the use is limited to research protocols. In patients with tamoxifen-associated polyps, levonorgestrel intrauterine device (IUD) has been shown to decrease polyp formation and may be considered as part of the management plan.
After hysteroscopic polypectomy, the collected specimens should be submitted to pathology for evaluation. On follow up of specimen pathology, polyps may have evidence of malignancy, and referral to gynecology oncology is recommended for further management. Complications associated with hysteroscopic polypectomy are rare, and the risk of intrauterine adhesion is low.
Conflicting data is available on the relationship between endometrial polyps and the risk of infertility. A prospective, randomized controlled trial showed that hysteroscopic polypectomy before intrauterine insemination is an effective measure and improved pregnancy rates. Also, the prevalence of endometrial polyps is significantly higher in infertile patients with Fallopian tube obstruction than in patients with Fallopian tube patency. In contrast, a retrospective review of patients who received in vitro fertilization (IVF) with known polyps during IVF cycles found no difference in pregnancy rates, miscarriage rates, or live birth rates. Currently, the expert recommendation is the removal of endometrial polyps prior to in-vitro fertilization.
Education should focus on the etiology and the management of abnormal uterine bleeding. A majority of polyps have benign pathology however, patients should also be counseled on the possible risk of malignancy. Discussion of malignancy carries a potentially harmful risk to the mental well-being of patients. Quality of life and future fertility is also impacted by the presence of endometrial polyps. Patients should be educated on the possibility of recurrence and modifiable factors to decrease these risks.
Endometrial polyps can have a negative impact on the quality of life and mental health in patients who have a poor understanding of the disease. Patients should be counseled on the disease pathology keeping in mind that terms like “lesion” or “neoplasm” may cause excessive concern for the patient.
Symptoms of abnormal uterine bleeding should be fully evaluated to rule out more serious etiologies, like malignancy. Endometrial polyps may be managed conservatively for low-risk patients or can be treated surgically. Recurrence risks should be discussed, and appropriate candidates may benefit from endometrial ablation and levonorgestrel intrauterine device to decrease these risks. In cases of surgical management, anesthesia consult should be considered for high-risk patients. Specialized surgical nurses will be responsible for preparing the patient before and after the procedure, intraoperative positioning, and arranging the correct surgical supplies. Nursing staff can follow up postoperatively to assess treatment success and inform the care team of any concerns.
All healthcare professionals should counsel the patient on the benefits, risks, alternatives, and outcomes of the procedure. Emphasis should be placed on communication and collaboration among team members to deliver safe and patient-centered care.
|||Tanos V,Berry KE,Seikkula J,Abi Raad E,Stavroulis A,Sleiman Z,Campo R,Gordts S, The management of polyps in female reproductive organs. International journal of surgery (London, England). 2017 Jul; [PubMed PMID: 28483662]|
|||Vanni R,Dal Cin P,Marras S,Moerman P,Andria M,Valdes E,Deprest J,Van den Berghe H, Endometrial polyp: another benign tumor characterized by 12q13-q15 changes. Cancer genetics and cytogenetics. 1993 Jul 1; [PubMed PMID: 8330280]|
|||Dal Cin P,Vanni R,Marras S,Moerman P,Kools P,Andria M,Valdes E,Deprest J,Van de Ven W,Van den Berghe H, Four cytogenetic subgroups can be identified in endometrial polyps. Cancer research. 1995 Apr 1; [PubMed PMID: 7882366]|
|||Xuebing P,TinChiu L,Enlan X,Jing L,Xiaowu H, Is endometrial polyp formation associated with increased expression of vascular endothelial growth factor and transforming growth factor-beta1? European journal of obstetrics, gynecology, and reproductive biology. 2011 Nov; [PubMed PMID: 21726930]|
|||Hu J,Yuan R, The expression levels of stem cell markers importin13, c-kit, CD146, and telomerase are decreased in endometrial polyps. Medical science monitor : international medical journal of experimental and clinical research. 2011 Aug; [PubMed PMID: 21804459]|
|||Runowicz CD,Costantino JP,Wickerham DL,Cecchini RS,Cronin WM,Ford LG,Vogel VG,Wolmark N, Gynecologic conditions in participants in the NSABP breast cancer prevention study of tamoxifen and raloxifene (STAR). American journal of obstetrics and gynecology. 2011 Dec; [PubMed PMID: 21872200]|
|||Bakour SH,Khan KS,Gupta JK, The risk of premalignant and malignant pathology in endometrial polyps. Acta obstetricia et gynecologica Scandinavica. 2000 Apr; [PubMed PMID: 10746849]|
|||Lee SC,Kaunitz AM,Sanchez-Ramos L,Rhatigan RM, The oncogenic potential of endometrial polyps: a systematic review and meta-analysis. Obstetrics and gynecology. 2010 Nov; [PubMed PMID: 20966706]|
|||Elfayomy AK,Soliman BS, Risk Factors Associated with the Malignant Changes of Symptomatic and Asymptomatic Endometrial Polyps in Premenopausal Women. Journal of obstetrics and gynaecology of India. 2015 May; [PubMed PMID: 26085741]|
|||Kolhe S, Management of abnormal uterine bleeding - focus on ambulatory hysteroscopy. International journal of women's health. 2018; [PubMed PMID: 29606892]|
|||Uglietti A,Mazzei C,Deminico N,Somigliana E,Vercellini P,Fedele L, Endometrial polyps detected at ultrasound and rate of malignancy. Archives of gynecology and obstetrics. 2014 Apr; [PubMed PMID: 24091484]|
|||Mourits MJ,De Vries EG,Willemse PH,Ten Hoor KA,Hollema H,Van der Zee AG, Tamoxifen treatment and gynecologic side effects: a review. Obstetrics and gynecology. 2001 May; [PubMed PMID: 11336777]|
|||Maia H Jr,Barbosa IC,Marques D,Calmon LC,Ladipo OA,Coutinho EM, Hysteroscopy and transvaginal sonography in menopausal women receiving hormone replacement therapy. The Journal of the American Association of Gynecologic Laparoscopists. 1996 Nov; [PubMed PMID: 9132309]|
|||Kupfer MC,Schiller VL,Hansen GC,Tessler FN, Transvaginal sonographic evaluation of endometrial polyps. Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine. 1994 Jul; [PubMed PMID: 7933016]|
|||Hassa H,Tekin B,Senses T,Kaya M,Karatas A, Are the site, diameter, and number of endometrial polyps related with symptomatology? American journal of obstetrics and gynecology. 2006 Mar; [PubMed PMID: 16522403]|
|||AAGL practice report: practice guidelines for the diagnosis and management of endometrial polyps. Journal of minimally invasive gynecology. 2012 Jan-Feb; [PubMed PMID: 22196255]|
|||Lieng M,Istre O,Sandvik L,Qvigstad E, Prevalence, 1-year regression rate, and clinical significance of asymptomatic endometrial polyps: cross-sectional study. Journal of minimally invasive gynecology. 2009 Jul-Aug; [PubMed PMID: 19573823]|
|||de Azevedo JM,de Azevedo LM,Freitas F,Wender MC, Endometrial polyps: when to resect? Archives of gynecology and obstetrics. 2016 Mar; [PubMed PMID: 26305029]|
|||Cravello L,Stolla V,Bretelle F,Roger V,Blanc B, Hysteroscopic resection of endometrial polyps: a study of 195 cases. European journal of obstetrics, gynecology, and reproductive biology. 2000 Dec; [PubMed PMID: 11074132]|
|||Yang JH,Chen CD,Chen SU,Yang YS,Chen MJ, Factors Influencing the Recurrence Potential of Benign Endometrial Polyps after Hysteroscopic Polypectomy. PloS one. 2015; [PubMed PMID: 26660149]|
|||Roberts H,Hickey M, Levonorgestrel intrauterine system for endometrial protection in women with breast cancer on adjuvant tamoxifen: A cochrane review summary. Maturitas. 2016 Jul; [PubMed PMID: 27180151]|
|||Deans R,Abbott J, Review of intrauterine adhesions. Journal of minimally invasive gynecology. 2010 Sep-Oct; [PubMed PMID: 20656564]|
|||Pérez-Medina T,Bajo-Arenas J,Salazar F,Redondo T,Sanfrutos L,Alvarez P,Engels V, Endometrial polyps and their implication in the pregnancy rates of patients undergoing intrauterine insemination: a prospective, randomized study. Human reproduction (Oxford, England). 2005 Jun; [PubMed PMID: 15760959]|
|||Sun Y,Zhang J,Bai W, Higher Prevalence of Endometrial Polyps in Patients with Fallopian Tube Obstruction: A Case-control Study. Journal of minimally invasive gynecology. 2019 Jul - Aug; [PubMed PMID: 30273685]|
|||Elias RT,Pereira N,Karipcin FS,Rosenwaks Z,Spandorfer SD, Impact of newly diagnosed endometrial polyps during controlled ovarian hyperstimulation on in vitro fertilization outcomes. Journal of minimally invasive gynecology. 2015 May-Jun; [PubMed PMID: 25580003]|