The Association of Body Mass Index and Ki67 Values in Patients with Endometrial Carcinoma

ALEXANDRU FURAU1#, MARIUS LUCIAN CRAINA2#, CRISTIAN FURAU3, TUDOR CONSTANTIN LUCA4#, BOGDAN CORNELIU ANDOR5#, DANIELA RADU6*, LAVINIA CRISTINA MOLERIU7*, DIANA CAMELIA BONTE8#, DANIELA OANA TOADER9#, GHEORGHE FURAU3 1Vasile Goldis Western University of Arad, Romania 2University of Medicine and Pharmacy Victor Babes Timisoara, Department XII, Discipline of Obstetrics and Gynecology, Timisoara, Romania 3Vasile Goldis Western University OF Arad, Department of Obstetrics and Gynecalogy, Romania 4University of Medicine and Pharmacy Victor Babes Timisoara, Department of Cardiology, Timisoara, Romania 5University of Medicine and Pharmacy Victor Babes Timisoara, Department XV of Orthopedics, Traumatology, Urology and Medical Imaging, Timisoara, Romania 6University of Medicine and Pharmacy Victor Babes Timisoara, Department Surgery, Timisoara, Romania 7University of Medicine and Pharmacy Victor Babes Timisoara, Department of Functional Sciences, Medical Informatics and Biostatistics Discipline, Timisoara, Romania 8University of Medicine and Pharmacy Victor Babes Timisoara, Department II, Discipline of Biochemistry and Pharmacology, Timisoara, Romania 9National Institute for Mother and Child Health, Alessandrescu–Rusescu, Polizu Clinical Hospital, Bucharest, Romania

Endometrial cancer is the result of abnormal cell growth originating from the endometrium and have the ability to invade or spread to other locations [1]. The first symptom is vaginal bleeding, between periods, or in postmenopausal patients. Other symptoms include dysuria, pain during intercourse or pelvic pain. Endometrial cancer is commonly diagnosed with endometrial biopsy or biopsy curettage.
According to the studies, the age at which it is found in more than 90% of cases is over 50 years old, but can also occur in women under 40 years old. If in the United States, over 80% of cases are diagnosed in stage 1, unfortunately in our countr y there are a number of risk factors incriminated in the occurrence of the disease. Approximately 40% of cases are related to obesity, diabetes, hypertension, an ovulatory infertility, nulliparity, infertility, polycystic ovary syndrome early menarche and late menopause, family history, BRCA gene mutations, a long exposure to estrogen, tumors secreting estrogen, tamoxifen treatment [6][7][8][9].
There have also been identified a number of protective factors against endometrial carcinoma: the use of combined oral contraceptives, the use of menopausal hormone replacement therapy.
In patients diagnosed with endometrial carcinoma, there was no consensus on levels and correlation with clinical pathologic factors and predictive value of HER-2 / neu alterations.
Endometrial carcinoma can be classified into two distinct groups: Type 1 endometrial cancers may arise from complex atypical hyperplasia and is pathogenetically linked to unopposed estrogenic stimulation. Approximately 80% of the endometrial carcinomas are type 1, i.e. low histological tumor type and grade (G1, G2). These cancers can occur in the event of persistent unopposed estrogen stimulation and tend to occur in perimenopausal women. They are generally preceded by endometrial hyperplasia and are estrogen receptor (ER) and/or progesterone receptor (PR) positive. Molecular changes associated with type 1 endometrial cancers include mutations by deletion / inactivation of the PTEN tumor suppressor gene (36-83%), microsatellite instability (20-40%), KRAS mutations (15-30%) and gain-of-function β-catenin mutation (25-40%) [10][11][12].
Type 2 endometrial cancers develop from atrophic endometrium and is not linked to hormonally driven pathogenesis. By contrast, type II endometrial cancers are histologically non-endometrioid cancers and have no association with the increased levels of endogenous or exogenous estrogen. They tend to appear in older women being very aggressive, with a tendency to lymph-vascular invasion, distant dissemination, and deep tissue invasion. They represent almost half of the mortality rates due to endometrial cancer. Genetic changes associated with Type II endometrial cancers include aneuploidy, p53 mutations (80-90%), p16 inactivation (40%), human epidermal growth factor receptor 2 overexpression (HER-2 / Neu (40-80%) and changes in E-cadherin expression (80-90%).
Deregulation of the mechanisms controlling cell proliferation and apoptosis is known in the case of malignant neoplasms. Recent data on Ki-67 and HER-2 / neu that are involved in these processes merged as valuable prognostic tools [13].
HER-2/neu protooncogene is associated with an unsatisfactory prognosis in in human breast and ovarian cancer. The significance of HER-2/neu in endometrial carcinoma is less clearly established. Some authors analyzed HER-2/ neu gene amplification by fluorescence in situ hybridization and protein overexpression measured by immunohistochemistry [14][15][16].

Experimental part Material and methods
We studied HER-2/neu amplification status and Ki-67 expression in hysterectomy specimens of endometrial carcinoma, determined by immunohistochemical analysis correlated with some clinical and pathological factors. The histological grade and stage of endometrial cancers were assigned according to the FIGO criteria. HER-2/neu signals were scored on histological sections in at least 150 neoplastic cells using a conventional microscope (Zeiss).
It is well known that increased cell proliferation is responsible for tumor growth. Among the markers of proliferation, our study suggested that Ki-67 provided additional information on clinical progression and prognosis.
The study included all patients who had been evaluated for vaginal bleeding in Obstetrics and Gynecology Department of Clinical Emergency County Hospital, Timisoara between 2016-2018. Before performing curettage biopsy, the thickness of the endometrium was measured with transvaginal ultrasonography. Of the 195 cases of uterus scraping, 19 cases were labeled as malignant endometrial pathology. After surgery, the anatomopathological results consisted of 13 cases of endometrial adenocarcinoma, 3 cases of mixed carcinoma and 3 cases of clear-cell carcinoma. Age of patients ranged between 54-82 years, with a higher frequency between 60-67 years (13 cases) [17][18][19].
The statistical analysis was performed using two different programs: Microsoft Excel and SPSSv17. For the descriptive statistics we calculated the central tendency parameters and the dispersion parameters, we made frequency tables and we plotted the most important results. For the statistical significance we performed a Mann -Whitney test, having α = 0.05 as the confidence level.

Results and discussions
It is important that malignant endometrial pathology can be detected early and the lesions are limited to the uterus in 70% of the cases. Unfortunately, in the case of our study group, type 1 endometrial cancers are found in only 5 cases, unlike other countries where most of endometrial cancers are diagnosed early (80% in the first stage) and the 5-year survival rate is about 95%. In any case, the 5-year survival rate is much lower if there is involvement of regional lymph nodes or distant metastasis (68% and 17%, respectively)as in our case where all cases were classified as Stage III and IV [20,21].
A common risk factor encountered in 15 cases was obesity that increases the risk of developing endometrial cancer; data suggests that a 2-to 3-fold greater than in people of normal weight (about 16 kg) increases the risk of developing endometrial cancer. Obesity is known to increase endogenous estrogen, because the presence of fat appears to be responsible for the conversion of androstenedione to estrogens in case of higher rates of overweight.
Upon all our diseased patients (N=19) we calculated the central tendency and dispersion parameters for the age and BMI (body mass index) parameters (Table 1) and as well for the nominal variables we calculated frequency tables ( Table 2). As well we plotted the most important results by using histograms (Figure 1), and a column and a pie chart (Figure 2).
After observing the characteristics of our data we tested to see if an increased BMI can influence the appearance of endometrial carcinoma. For this we applied a Mann-Whitney test and we obtained extremely significant differences between this two mean BMI values. The diseased patients are having a higher BMI value. In the end of our study we tested the possible association between the Ki-67 values and the HER-2 / neu status in our two groups (patients with or without endometrial carcinoma) and we obtained extremely significant differences between the groups (p<0.001) .
So we can say that Ki-67 values are increasing proportionally with the carcinoma staging.

Conclusions
According to published studies, we noticed that Ki-67 reactivity in 2/3 of our cases, increased along with the grade and stage of tumours and the myometrium invasion progressed along with the presence of lymph vascular space invasion. These findings indicate a severe deregulation of the cell cycle in cases with more aggressive oncogenic behaviour. However, data prognostic significance of Ki-67 in predicting endometrial carcinoma are variable.