A sarcoma oncologist will generally give you an edge.  Frank discussion of effectiveness of adjuvant [see next section] or other therapies is very important. Except for those which are CD117 positive and respond to Glivec, the tumors' response rate to chemotherapy or radiation treatment is not high. The success rate is on the order of 1/3 of the tumors showing response...the cure rate, however is very, very low.  However, these drugs can, if successful, buy you time. Because none of the chemotoxic agents are very effective with LMS, there are new drugs being tested all the time. 

Unless a tumor is growing in a sensitive place, it is often not the local recurrence which is eventually fatal, but the metastases--either by bulk, or by other effects.  Chemotherapy or radiation treatment can keep the bulk and effects of the metastases under control, but at the expense of your bone marrow and/or liver.

Furthermore, radiation and chemotherapy have some permanent effects on bone marrow.  Chemotherapy can also injure liver.  Too many treatments, and your bone marrow no longer makes blood cells [see Myelodysplasia (My-ehh-low  dis-play-zya)], or your liver no longer works.  At these points, the oncologists will no longer give you chemotherapy or radiation.  

This is another reason why surgical resection is the management of choice, if it is possible.

For more information on the approach to treatment of leiomyosarcoma, 
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