Inclusion Criteria:

- Soft tissue sarcoma members histologically confirmed

- Tumor primitive complete excision with margins greater than or equal to 10 mm in the
soft tissue in all directions during the initial surgery.

A sub-centimeter margin is authorized under an anatomic barrier (fascia, fascia,
inter-osseous membrane, periosteum), if surgery is R0 a margin sub-centimeter depth is
allowed for superficial tumors if the underlying fascia RESECTED is not invaded.

- Primitive tumors without breaking initial tumor and without tumor residue in the
systematic recovery in case of incomplete initial excision margins or doubtful

- WHO less than or equal to 2

- Age greater than or equal to 18 years

- Review extension negative (normal chest CT)

- Information and monitoring possible

- Patient affiliated to social security

Exclusion Criteria:

- Previously treated local sarcoma relapse

- Visceral or lymph node metastases

- pre-operative treatment (chemotherapy or radiotherapy)

- PNET, alveolar rhabdomyosarcoma, Darrier-Ferrand sarcoma

- excision margins of less than 10 mm in one direction or doubtful or unspecified,
except under an anatomic barrier (fascia, fascia, inter-osseous membrane,
periosteum), if surgery is R0 and tumors if the superficial fascia underlying
RESECTED is not invaded.

- Break-tumor during the initial surgery, or residual tumor at second surgery

- Chemotherapy

- Delay between surgery R0 margins greater than or equal to 1 cm (initial surgery or
recovery) and the start of radiotherapy exceeding 8 weeks

- History of radiation on the Member

- History of cancer (except carcinoma in situ of the cervix and basal cell skin cancer
or in complete remission for over 5 years)

- Pregnant Women

- Patients under guardianship or curatorship