Analysis of pre-and postoperative pathological findings in endometrial cancer

Łukasz Cwonda, Katarzyna Wójcik-Krowiranda, Tomasz Michalski, Joanna Stefaniak-Wrońska, Andrzej Bieńkiewicz Received: 19.05.2017 Accepted: 10.08.2017 Published: 31.08.2017 © Curr Gynecol Oncol 2017, 15 (2), p. 105–112 DOI: 10.15557/CGO.2017.0010 Łukasz Cwonda, Katarzyna Wójcik-Krowiranda, Tomasz Michalski, Joanna Stefaniak-Wrońska, Andrzej Bieńkiewicz


E
ndometrial cancer is the most common gynecologic malignancy in Poland.Low parity, obesity, diabetes as well as limited physical activity among Polish women are emphasized as the major factors in the pathogenesis of this cancer.The incidence rates in Poland are higher than the European Union average (23.4 vs. 17.9/100,000women -age standardized rate, EUCAN 2012).In 2013, a total of 5,706 new cases were registered, which accounts for 7.3% of all malignancies and ranks this cancer fourth in terms of incidence among females.Mortality rates for this cancer in Poland reached 1,243 in 2013 (1) .The peak incidence for endometrial carcinoma is observed in the peri-and postmenopausal period.Risk factors that may predispose to endometrial cancer include early menarche, late menopause, and the use of hormone replacement therapy without gestagen (2) .The impact of obesity on the development of the disease is associated with elevated serum estrogen levels due to peripheral conversion of androgen precursors to estrogens in the adipose tissue (3,4) .An increased risk of endometrial cancer is also observed in nulliparous women, particularly after long-term infertility treatment (5,6) .There are also genetic risk factors for endometrial cancer, such as hereditary nonpolyposis colorectal cancer (i.e.Lynch syndrome).Abnormal uterine bleeding, which may obviously differ in intensity but typically occurs between menses or after menopause, is the main symptom of endometrial cancer that is observed in almost 90% affected women.In rare cases, serous, serous-bloody or even purulent vaginal discharge may occur.Pelvic pain, weight loss, and general malaise usually occur in more advanced stages of the disease (7,8) .The diagnosis of endometrial cancer is based on histopathological examination which is usually conducted in duplicate.First, material obtained with the dilation and curettage (hysteroscopy or biopsy) is assessed, which is followed by an evaluation of samples obtained during surgical procedure.Therefore, surgery is not only a part of treatment, but it also allows to ultimately determine the type and the clinical stage of cancer.Discrepancies between the initial and the final diagnosis may lead to inappropriate therapeutic decisions, which may in turn result in an unfavorable course of therapy associated with either excessively or insufficiently radical treatment.

AIM OF THE STUDY
The aim of the study was to compare pre-and postoperative histopathological findings in women with endometrial cancer as well as to evaluate the diagnostic value of dilation and curettage in patients with postoperatively diagnosed endometrial cancer.

MATERIAL AND METHOD
This was a retrospective study based on the results of pre-and postoperative histopathological examinations in patients treated surgically in the Clinical Department of Gynecologic Oncology in Nicolaus Copernicus Memorial Specialist Hospital in Łódź between 2010 and 2015.Initially, the comparison was performed in a group of 200 patients with postoperative histopathological findings of endometrial cancer.However, patients whose histopathological examination after dilation and curettage indicated endometrioid endometrial cancer but did not assess grading were excluded from the study to improve the value of comparison.Final analysis included a group of 115 women with endometrial cancer.The youngest patient at the time of surgery was 31 years old and the oldest was 84 years.The mean age was 62.43 years (median -62, standard deviation, SD -10.73).(Fig. 1).
In most cases, curettage procedure and histopathological evaluation of the obtained tissue material were performed outside the Clinical Department of Gynecologic Oncology in Nicolaus Copernicus Memorial Specialist Hospital in Łódź.

RESULTS
Endometrioid endometrial cancer was the most common cancer in the evaluated material obtained by curettage in the study group.We assessed grading for this type of cancer (Tab. 1

Other types of endometrial cancer
Among 2 patients with preoperatively diagnosed serous carcinoma, consistency between pre-and postoperative findings was reported in 1 patient, whereas G2 endometrioid cancer was revealed in the other patient (50%).
Postoperative evaluation revealed the coexistence of endometrioid and mucous cancer in two patients preoperatively diagnosed with mucosal cancer.
Of the 2 cases of preoperatively diagnosed sarcoma, histopathological examination of postoperative material showed sarcoma in 1 case and carcinosarcoma in the other.In a group of 5 patients, the preoperative diagnosis of carcinosarcoma matched postoperative examination in 100%.
Fully compliant histopathological results were also obtained in 1 patient with anaplastic cancer.In 3 patients with a preoperative diagnosis of clear cell carcinoma, compatibility of the initial histological diagnosis was achieved in 2 patients, whereas 1 patient was postoperatively diagnosed with carcinosarcoma.
One patient was preoperatively diagnosed with both serous carcinoma and clear cell carcinoma; however, postoperative examination did not confirm the initial diagnosis and revealed G2 endometrioid endometrial cancer.
Of the 2 patients preoperatively diagnosed with endometrial cancer coincident with clear cell carcinoma, histopathological compatibility was obtained in 1 patient.The other patient was ultimately diagnosed with serous carcinoma.
In a group of 4 patients preoperatively diagnosed with endometrial hyperplasia (proper description of the type of hyperplasia is missing), 3 cases of G2 endometrioid cancer and 1 case of G1endometrioid cancer were eventually identified.
In total, final diagnosis matched the initial one in 86.96% of patients with endometrial cancer diagnosed in postoperative material.

DISCUSSION
The compliance of histopathological findings obtained by curettage with the postoperative material is very important.
Preoperative histopathological findings are crucial when planning therapeutic approach.A different extent of surgery is planned for a patient preoperatively diagnosed with endometrioid endometrial cancer, and a different one for a patient with type II endometrial cancer (clear cell, serous).The range of surgical treatment in a patient with a low-grade tumor differs from the one in a patient with more malignant cancer (G3) (9) .In many countries, patients with endometrial cancer of low malignant potential receive surgical treatment outside oncology centers.However, those with high-grade endometrial cancer found preoperatively are treated in oncology centers specialized in this type of surgeries.
The above-mentioned inconsistency may be due to the differences between histopathology laboratories.As mentioned before, the vast majority of curettage procedures were performed outside the Clinical Department of Gynecologic Oncology in Nicolaus Copernicus Memorial Specialist Hospital in Łódź, where all final surgical procedures were performed.Histopathological examinations were conducted in different histopathological laboratories and by many histopathologists.The influence of such a discrepancy on the consistency of the histopathological findings was also described by Mitchard and Hirschowitz (12) .The data may suggest the need for conducting preoperative histopathological consultation of specimens in tertiary gynecologic oncology centers.Consultation should be absolutely considered in cases where the assessment lacks tumor grading, which is crucial for planning a therapeutic approach (9) .Every finding of complex endometrial hyperplasia, especially atypical one, should be consulted by a pathologist with extensive experience in gynecologic oncology (24) .Lack of experience of the surgeon who performs dilation and curettage may also contribute to the discussed discrepancy.This may be associated with the collection of material from a small, unrepresentative endometrial surface.Cancerous lesions, especially in the initial stage, may be limited to a small portion of the mucosa.According to Epstein et al., 58% of polyps, 60% of complex atypical hyperplasias and 11% of endometrial cancers are missed during dilation and curettage in women with postmenopausal bleeding and endometrial width of more than 5 mm (25) .An inadequate assessment of the lesion can also be observed if the depth of mucosal sampling is insufficient.
which would require a different, more radical therapeutic approach, seems to be of crucial importance.Alternative, more precise diagnostic methods, such as hysteroscopy, could be employed to solve the problem (26) .Hysteroscopy allows for an accurate visualization of the uterine cavity and thus target-sampling as well as a simultaneous removal of some lesions using proper operational instruments.According to the latest research, hysteroscopy does not significantly increase the risk of tumor spreading into the peritoneal cavity.Also, no effects on the mortality of patients who underwent this procedure have been reported (27) .The procedure is associated with lower rates of grading discrepancy compared to postoperative findings (11) .
Recently, an increasing number of reports on the high diagnostic sensitivity in the estimation of endometrial pathology may be found in medical databases for some modern imaging techniques, such as 3D-transvaginal ultrasound or magnetic resonance imaging (28,29) .Although lower invasiveness and lower risk of complications are undoubtedly advantages of these techniques, they cannot replace the classical pathological evaluation as they do not allow for obtaining tissue samples needed for diagnosis.

CONCLUSIONS
1. Consultation of preoperative specimens with pathologists who have extensive experience in oncology before making medical decisions seems to be an appropriate way of reducing the discrepancies of preoperative and postoperative findings in endometrial cancer.2. Treatment and postoperative assessment in medical centers experienced in gynecologic oncology may have an impact on the choice of adequate treatment for patients with endometrial cancer.