Observational Study of Women With Endometrial Cancer Who Receive the Standard Treatment for Their Disease

Screening Inclusion Criteria:

ECOG performance status 0-1 or KPS ≥ 70%
Age ≥ 18 years
Endometrioid adenocarcinoma histologic diagnosis on endometrial biopsy or dilatation and curettage confirmed at the enrolling institution
No evidence of extrauterine disease, or suspicious pelvic lymph nodes, or distant metastases, or cervical invasion on pre-operative conventional imaging studies (Pelvic +/- Abdomen CT or MRI or sonogram, or body PET scan) and physical examination (uterine confined by exam and imaging )
Suitable candidate for surgery
Planned surgical treatment including hysterectomy in combination with SLN biopsy and a bilateral salpingo-oophorectomy
No history of second primary cancer (invasive or in situ) within the past 5 years, not including non-melanoma skin cancer
Approved and signed informed consent
No history of neoadjuvant chemotherapy or radiotherapy for endometrial cancer
No history of prior pelvic or abdominal radiotherapy

Screening Exclusion Criteria:

Extrauterine disease, or gross lymph node involvement, or cervical invasion suspected on pre-operative imaging studies and physical examination (disease not uterine confined clinical stage > I)
Contraindication for SLN mapping
The planned treatment is not surgery, or the surgical treatment does not include hysterectomy in combination with SLN biopsy and a bilateral salpingo-oophorectomy

Eligibility Inclusion Criteria

Patients will be classified in the study cohort (part 2; n=182) according to surgical treatment received, final post hysterectomy and staging pathologic report, and planned adjuvant treatment. The inclusion criteria are specified below.

Study Cohort (n=182)

A patient will be enrolled in the study cohort if all the following criteria are met:

At surgery, the patient must undergo:

Hysterectomy
Bilateral salpingo-oophorectomy, unless already previously performed
Bilateral pelvic SLN mapping (bilateral sentinel nodes are negative for malignancy)

On the final pathologic report, the patient must have a diagnosis of:

Stage I intermediate-risk endometrial endometrioid cancer (Grade 1 or Grade 2 with ≥ 50% myometrial invasion or Grade 3 with <50% myometrial invasion, including non-invasive disease)
Negative pelvic peritoneal cytology

Adjuvant treatment as recommended by the multidisciplinary team must be as follows:

No adjuvant treatment, or
Intravaginal radiation only

Eligibility Exclusion Criteria

There is intra-operative detection of extra-uterine disease or grossly involved lymph nodes
Presence of any positive pelvic nodes including micrometastasis and isolated tumor cells (ITC)
Hysterectomy is not performed
Bilateral salpingo-oophorectomy is not performed, unless already previously performed
Failed unilateral or bilateral SLN mapping
Patient undergoes a complete unilateral or bilateral pelvic lymphadenectomy
Patient undergoes a radical type C hysterectomy
Stage IA endometrioid cancer Grade1 or 2 and myometrial invasion <50%
Stage IB Grade 3 endometrioid cancer
Non-endometrioid histology: Serous, clear cell, carcinosarcoma, undifferentiated, or de-differentiated histology noted on final hysterectomy pathology
Empty unilateral or bilateral sentinel lymph nodal packet(s)
Positive peritoneal cytology