Abstract: Aim: Morphologic examination of endometrial polyps and assess the occurrence of endometrial cancer. Materials & Methods: One hundred sixty cases of endometrial polyps received at the department of Pathology of a tertiary care hospital over 31 months i.e., from January 2014 and July 2016 were analysed. The clinical data was retrieved from the medical records department. Results: Out of the 160 cases of endometrial polyps, 94.4% of the endometrial polyps were non neoplastic & 5.6% were neoplastic. The mean age of presentation of non-neoplastic polyps was 45 years (21-76 years) & neoplastic polyps was 52 years (42-62 years). The mean size of non-neoplastic polyp was 2.4 cm (0.5-9 cm) & neoplastic polyp was 4.5cm (1.5-9cm). The non-neoplastic polyps were benign endometrial glandular polyp (83.7%), leiomyomatous polyp (2.2%), adenomyomatous polyp (1.1%) & stromomyoma (0.5%). The neoplastic polyps encountered were endometrial carcinoma type 1 (1.67%), endometrial carcinoma type 2 (0.5%), endometrial stromal sarcoma (1.67%), adenosarcoma (0.5%) & malignant mixed mullerian tumor (0.5%). Post-menopausal bleeding was seen in 27% of patients. Immunohistochemistry was performed in 3 of the cases. Tamoxifen induced endometrial polyp were seen in 1.67%. Conclusion: Endometrial polyps are rarely associated with malignancy, as most of them are hyperplastic glandular polyps. Multiple risk factors such as age, multiparity, tamoxifen usage show higher association with malignancy. Post-menopausal bleeding cases needs to be thoroughly evaluated for presence of endometrial malignancy. Histopathological evaluation of resected polyps proves the nature of the disease.
Key Words: Endometrial Carcinoma, Endometrial polyps, Malignant mixed mullerian tumor, Post-menopausal bleeding, Stromal sarcoma |
Introduction:
Endometrial polyps are an overgrowth of endometrial tissue. They are covered by a lining epithelium and are composed of variable amounts of glands, stroma and blood vessels. It is frequently encountered in women of reproductive age group with history of abnormal menstrual cycle. Most often the intraepithelial neoplastic (IEN) lesions manifested as polyps and the literature do support the association of endometrial polyp with carcinogenesis. [1,2]
Endometrial polyps are one of the causes for abnormal uterine bleeding. The factors that are usually associated with endometrial polyps are age, menopausal status, hormonal therapy, tamoxifen usage, polyp diameter and presence of symptoms such as abnormal uterine bleeding, spotting in between menstrual cycles, abdominal pain and mass. One of the well-known factors for neoplastic changes in endometrial polyp is post-menopausal status and older age. The progression of simple to complex endometrial hyperplasia happens over years depending upon the accumulation of specific genetic aberrations, which explains the post-menopausal state and older age being the risk factors. Lately, there is increased incidence of endometrial polyps in patients of breast cancer on tamoxifen treatment. [2-4]
Endometrial polypoid lesions are picked up with transvaginal ultrasound examinations in both symptomatic and asymptomatic cases. [5] Hysteroscopic polypectomy or curettage are commonly done and specimen is sent for further investigations to rule out any association of neoplasia. But, only polypectomy remains valuable as it gives the chance of removing the polyp with the stalk so that risk of malignancy can be confidently estimated. [3] Polyps can show wide spectrum of alterations from being normal to malignant thus, has to be properly studied for the right management and treatment. It is necessary to differentiate frank polypoid lesions and carcinomas as some polypoid lesions tend to mimic endometrial neoplasms like stromal sarcoma, malignant mixed mullerian tumor. Association, pathogenesis and frequencies of endometrial polyp with neoplasia is not understood fully yet. [6,7]
Hence this study was done to examine the histomorphologic features of endometrial polyp and assess the occurrence of endometrial cancer.
Materials and Methods:
One hundred sixty cases of endometrial polyps received at department of Pathology of a tertiary care hospital over 31 months i.e., from January 2014 and July 2016 were analyzed. The clinical data was retrieved from the medical records department. The women were subjected to hysteroscopic polypectomy or curettage of the polyps. Women in all age group diagnosed with endometrial polyps were considered. Factors like age, symptoms, tamoxifen usage, and menopausal status were essentially studied, to understand the precipitating factors for polyp and cancers manifesting as polyps. Frequencies of histological subtypes were analyzed with special regards to neoplastic endometrial polyps.
Results:
During the study period, 160 cases of endometrial polyps were analysed. Among which, majority (94.4%) comprised of non-neoplastic lesions & only 5.6% polyps were neoplastic. The mean age of presentation of non-neoplastic polyps was 45 years (21-76 years) & neoplastic polyps were 52 years (42-62 years). Post-menopausal bleeding was seen in 27% of patients. The mean size of non-neoplastic polyp was 2.4cm (0.5-9cm) & neoplastic polyp was 4.5cm (1.5-9cm). [Figure 1]
 |
Figure 1: Gross appearance of endometrial polyps. AB: Benign Polyps of endometrium. CD: Malignant Polyps of Endometrium, Endometrial carcinoma Type 1 (C) & Malignant mixed mullerian tumor presenting as a polyp (D). |
 |
Figure 2: Non-neoplastic polyps of Endometrium. AB: Adenomyomatous polyp showing the endometrial glands in a leiomyomatous stroma. CD: Infarction & necrosis in an endometrial polyp |
The various histopathological diagnoses are shown in Table 1. The non-neoplastic lesions were more common than neoplastic lesion. The most common lesion was benign endometrial glandular polyp of 141 cases (83.7%). [Figure 2] The most common neoplastic lesion was endometrial carcinoma type 1 & endometrial stromal sarcoma of 1.67% each. Immunohistochemistry was performed in 3 of the cases for confirmation of diagnosis. [Figure 3] Tamoxifen induced endometrial polyp were seen in 1.67% cases.
 |
Figure 3: Neoplastic polyps of Endometrium. AB: Endometrioid endometrial adenocarcinoma. Endometrial neoplastic glands are invading the stroma. CD: Endometrial stromal sarcoma with CD 10 positivity. E-G: Malignant mixed mullerian tumor (Carcinosarcoma) showing atypical glands embedded in a sarcomatous stroma. H: CD 10 is positive stromal cells. I-J: Adenosarcoma. Benign glands and sarcomatous stroma. KL: Malignant mixed mullerian tumor (Carcinosarcoma) showing malignant glands with sarcomatous stroma. Heterogenous elements like cartilage are present. [L] |
| Table 1: Various histopathological diagnoses among the endometrial polyps |
|
Histopathological diagnosis |
Cases |
% |
Non- Neoplastic |
Benign Endometrial Glandular Polyp |
141 |
83.7 |
Leiomyomatous Polyp |
4 |
2.2 |
Adenomyomatous Polyp |
2 |
1.1 |
Stromomyoma |
1 |
0.5 |
Tamoxifen induced endometrial polyp |
3 |
1.67 |
Neoplastic |
Endometrial Carcinoma Type I |
3 |
1.67 |
Endometrial Carcinoma Type II |
1 |
0.5 |
Endometrial Stromal Sarcoma |
3 |
1.67 |
Adenosarcoma |
1 |
0.5 |
Malignant mixed mullerian tumor (Carcinosarcoma) |
1 |
0.5 |
|
Total |
160 |
100 |
Most of the cases presented with abnormal bleeding like menorrhagia, spotting or post-menopausal bleeding and some were asymptomatic and picked up on ultrasound examination or per vaginal examination. The results of percentage of cases presented with various symptoms has been tabulated. [Table 2]
| Table 2: Endometrial polyp cases with various clinical details |
| Complaints |
Percentage of cases |
Post-Menopausal Bleeding |
27% |
Menorrhagia |
26% |
UV Prolapse |
12.6% |
Fibroid Uterus |
7.2% |
Post-Tamoxifen Usage In Breast Cancer |
2.7% |
Others |
25.5% |
Total |
100% |
Discussion
The study was conducted to assess the occurrence of neoplasms in endometrial polyps. In the present study, the prevalence of neoplastic lesions was 5.5%, which is in concordance with records in the literature. (0.2-12.9%). [7]
The present study showed similar results when compared to previously done studies on age-dependent association for endometrial polypoid lesions. Benign type of polyps were encountered in both younger (as young as 21 years) and older (as old as 76 years) age. Malignant polyps were more likely to be encountered in older age group. The age group for non-neoplastic and neoplastic polypoid lesions according to this study is 21-76 years and 42-62 years respectively.
Highlighting the malignant polyps, the age group manifesting neoplastic endometrial polyps were 42-62 years, inclining more towards the older age group. Also this age group falls in the category of peri-menopausal and post-menopausal group. This supports age-dependent association of polyps and malignancy in the polyps. [7]
The consideration of sizes of polyp is least understood and this study has made an attempt to understand their importance in the diagnosis. According to the literature, the sizes of polyp were ranging from 3-45 mm.(8) We encountered sizes as big as 9 cm in both malignant and non-malignant endometrial polyps and sizes were can highly varying ranging from 0.5cm to 9 cm. The drawback of considering this factor for diagnostic and management purpose is that some are hysterectomy specimens and some are curettaged. The polyps in the specimen with the stalk and base provides the accurate size and helps to understand the etiopathogenesis, which are encountered only in hysterectomy specimens. In our study 40% (72 out of 179) of the specimens received by the pathology lab was polyp with post-hysterectomy or polyps bottled after polypectomy and, the remaining 60% were curettaged specimens. Only when the stalk and base are available the nature of the lesion can be appreciated and be more accurate, but becomes difficult to understand because of this drawback. Knowing the sizes of polyps that are worrisome (that can be known by ultrasound examination) can help the physician in selecting the proper treatment and efficient management. The mean size can aid in indication for hysterectomy which has to be the last mode of treatment especially in reproductive women, as it would affect their reproductive life. The mean size from the results is 2.4cm for non-neoplastic and 4.5cm for neoplastic polyps. Most of the non- neoplastic polyps were smaller than the neoplastic and below 4cm. More than 4cms can be the indication to be screened for any neoplastic changes. But, still because of the drawbacks like number and nature of such specimens leads to the insignificance of understanding the sizes. Some studies have had the results of insignificance of knowing the sizes. [7] They could have significance if more number of hysterectomy or polypectomy specimens are carefully studied, rather than curettaged.
The highest number of cases have presented with post-menopausal bleeding and menorrhagia. Similarly in one of the studies the post-menopausal bleeding was accounting to 35.6% and menorrhagia of about 34.7%. [7] Yet in both the cases post-menopausal bleeding is the commonly encountered symptom amounting to the fact polyps occur more commonly in post-menopausal women. One of the most important observations is that women on tamoxifen for breast cancer patients also presented with endometrial polyp. Though it is only 2.7% of the cases presenting with such history, one of the studies had observed 17.7% of the cases with similar background. [3] Hence, there is an increased risk of endometrial polyps occurring post breast cancer therapy.
The number of neoplastic polyps encountered in the study is less (5.5%), but is significantly more than the previously done studies. According to the studies, association of malignancy associated with endometrial polyps were 0.8% in 2002 and 2.7% in 2015. [3,7] Hence, such association is increasing over years. This indicates that polyp has to be a thought for manifesting any underlying neoplasm of uterus. Here, the most common most common neoplastic lesion was endometrial carcinoma type 1 & endometrial stromal sarcoma. This result in comparison with previous studies is little different, as adenosarcoma is the most common. [7] Immunohistochemistry was performed in 3 of the cases, using markers such as p16 which was used to provide the ultimate differential diagnosis.
To conclude, endometrial polyps have rare association with malignancy and is quite significant. Their manifestation is more common in elderly, and in women of peri- and post-menopausal age group. Knowing the size appears to be insignificant as there is no much difference in neoplastic & non neoplastic polyps. However, larger polyps require further evaluation to rule out malignancy. A thorough evaluation of post and peri-menopausal women presenting with any abnormal bleeding needs to be done. A multimodality approach with radiology, gynecology and histopathology is required to reach a final diagnosis & plan the next level of treatment. Immunohistochemistry aids in reaching the exact nature of the lesion.
References
- Carlson JW, Mutter GL. Endometrial intraepithelial neoplasia is associated with polyps and frequently has metaplastic change. Histopathology 2008;53(3):325-32.
- Kelly P, Dobbs SP, McCluggage WG. Endometrial hyperplasia involving endometrial polyps: report of a series and discussion of the significance in an endometrial biopsy specimen. BJOG. 2007;114(8):944-50.
- Savelli L, De Iaco P, Santini D, et al. Histopathologic Features and Risk Factors for Benignity, Hyperplasia, And Cancer In Endometrial Polyps. Am J Obstet Gynecol. 2003 ;188(4):927-31.
- Diwakar RK. Endometrial polyp: short review of literature and treatment options. Is every polyp malignant? Indian J Med Case Reports 2015;4(1):8-11.
- Gambadauro P, Martínez-Maestre MÁ, Schneider J, Torrejón R. Endometrial polyp or neoplasia? A case-control study in women with polyps at ultrasound. Climacteric. 2015;18(3):399-404.
- McCluggage WG, Alderdice JM, Walsh MY. Polypoid uterine lesions mimicking endometrial stromal sarcoma. J Clin Pathol 1999;52:543-6.
- Hileeto D, Fadare O, Martel M, Zheng W. Age dependent association of endometrial polyps with increased risk of cancer involvement. World J Surg Oncol. 2005;3(1):8.
|
