The purpose of the SENTRY (Stability Enhanced Transcriptional Analytics) Study is to test whether combining a unique analytical approach with changes in platelet RNA expression accurately diagnoses ovarian cancer. Using retrospective data, the investigators have developed an approach that appears to accurately classify ovarian cancer with relatively high sensitivity and specificity. The SENTRY Study will build upon these retrospective analyses to prospectively recruit women with ovarian cancer or an ovarian mass (and healthy control women), obtain platelet RNA samples from whole blood, and perform validation analyses to test our hypothesis.

Study Populations 1 and 2: Women with a Recent Diagnosis of an Ovarian or Pelvic Mass (n=215)

Inclusion Criteria:

1. Women aged 21 years or older
2. Diagnosed with any type of ovarian or pelvic mass
3. Treatment naïve for current ovarian cancer (if cancer has been diagnosed)
4. The treating medical provider(s) are planning to perform a biopsy, surgery, or other diagnostic procedure to further evaluate the ovarian or pelvic mass (if not already diagnosed prior to consent)

Exclusion Criteria:

1. Any other active malignancy
2. Other diagnosis of any cancer within the last 6 months except for non-melanoma skin cancer or carcinoma in situ of the cervix
3. Treatment for any cancer within the last 6 months except for non-melanoma skin cancer or carcinoma in situ of the cervix. Adjuvant endocrine therapy or other maintenance therapy is allowed.
4. Currently receiving chemotherapy, radiation therapy, or other treatments for ovarian cancer
5. Has already undergone complete ovarian mass resection
6. Unable to provide blood sample

Study Population 3: Control Women without Ovarian Cancer (n=30)

Inclusion Criteria:

1. Women aged 21 years or older

Exclusion Criteria:

1. Any active malignancy or diagnosis of cancer within the last 6 months except for non-melanoma skin cancer or carcinoma in situ of the cervix
2. Treatment for any cancer within the last 6 months except for non-melanoma skin cancer or carcinoma in situ of the cervix
3. Hospitalization or surgery (other than minor surgery such as mole removal) within the last 8 weeks
4. Renal failure (defined as eGFR < 60 mL/min/1.73m² or on dialysis)
5. Liver failure (defined as having hepatic encephalopathy of any degree, OR moderately severe coagulopathy defined as INR ≥ 1.5, OR known cirrhosis, OR ALT of ≥ 10X ULN, OR total bilirubin of ≥ 3.0 mg/dL, OR diagnosis of liver failure)
6. Decompensated or end-stage heart failure (defined as ACC/AHA Stage C or Stage D heart failure)
7. Poorly controlled diabetes mellitus (defined as a HbA1c > 9.0%)
8. Venous thrombosis, myocardial infarction, or stroke within the last 8 weeks
9. Currently pregnant or have been pregnant within the last 12 weeks
10. Any blood product transfusion within the last 8 weeks
11. Personal history of ovarian cancer at any time
12. History of bilateral salpingo-oophorectomy
13. History of oophorectomy
14. Unable to provide blood sample

Participants will be patients in the Huntsman Cancer Hospital Clinics in Salt Lake City, Utah.