The purpose of this study is to find out if giving a dose of heated chemotherapy in the abdomen immediately after surgery that is done to remove uterine leiomyosarcoma type of cancer will help lower the risk of the cancer coming back in the future.

Primary Objective:

- To assess the efficacy of cytoreductive surgery with gemcitabine HIPEC followed by postoperative systemic chemotherapy with dacarbazine in subjects with locally recurrent uterine LMS.

Secondary Objectives:

• To assess the safety of cytoreductive surgery with gemcitabine HIPEC in subjects with locally recurrent uterine LMS.
• To assess the 6 month and 12 month intraabdominal relapse free survival in subjects with locally recurrent uterine LMS
• To determine quality of life prior to therapy (within 28 days prior to surgery with HIPEC), 4 to 6 weeks after surgery with HIPEC, and then at Cycle

Inclusion Criteria:

1. Histologically confirmed diagnosis of uterine leiomyosarcoma (LMS) with evidence of local recurrence.
2. Imaging provides evidence of locally recurrent uterine LMS.
3. Candidate for potentially radical, maximal effort cytoreductive surgery at the discretion and expertise of the treating physician.
4. Age ≥ 18 years.
5. Life expectancy > 3 months.
6. Women of childbearing potential (WOCBP) will have a negative pregnancy test ≤ 7 days prior to surgery (this test can be omitted if subject is post menopausal by either surgery or elevated FSH)
7. Eastern Cooperative Oncology Group (ECOG) Performance Status ≤ 2.
8. Hemoglobin (HGB) ≥ 9 g/dL.
9. White blood cell count (WBC) ≥ 3.0 K/ul.
10. Absolute neutrophil count (ANC) ≥ 1.5 K/ul.
11. Platelets (PLT) ≥ 100 K/ul.
12. Total bilirubin within normal institutional limits.
13. Serum glutamic oxaloacetic transaminase (SGOT/Serum glutamic pyruvic transaminase (SGPT) < 2.5 x institutional upper limit of normal (ULN).
14. Creatinine < 1.5 x ULN or creatinine clearance > 60 mL/min according to Cockroft Gault formula.
15. Prothrombin Time (PT) such that international normalized ratio (INR) is < 1.5 (or an in range INR, usually between 2 and 3, if a subject is on a stable dose of therapeutic warfarin or low molecular weight heparin) and a partial thromboplastin time (PTT) < 1.2 times control.
16. Serum albumin ≥ 2.5 g/dL.
17. Ability to understand and the willingness to personally sign the written IRB approved informed consent document.

Note that this study does not allow the use of a legally authorized representative

Exclusion Criteria:

1. Recurrence of LMS within less than 6 months after the last dose of gemcitabine.
2. Active extra abdominal disease including active malignant pleural effusion. Subjects who have been successfully treated with neoadjuvant chemotherapy and no longer have (malignant) pleural effusions may be included.
3. Prior gemcitabine given in non adjuvant setting.
4. Prior treatment with dacarbazine.
5. Active infection requiring antibiotics.
6. Unresolved toxic effects of prior therapy (except alopecia). Resolution is considered ≤ Grade 1 per NCI CTCAE, version 5.0.
7. Pregnant.
8. Breast feeding.
9. Presence of metastatic liver disease