Prospective Study of Stereotactic Body Radiation Therapy for Thymoma Inoma: Therapeutic Effect and Toxicity Assessment
Condition: Thymoma; Thymic Tumor
MeSH terms: Thymoma; Thymus Neoplasms
Study type: Interventional

Summary: 
      For patients with unresectable or recurrent disease, radiation is routinely administered,
      often in combination with systemic chemotherapy. However, because of wide range of radiation,
      more complications of conventional radiotherapy limit its treatment dose. The local
      recurrence rates of conventional radiotherapy are dissatisfied.Stereotactic body radiation
      therapy(SBRT) well solved the problem above. On the one hand, by improving the single dose,
      it not only shortens the total radiation treatment, but also increases the total dose of
      equivalent biological effects.
    

Detailed description: 
      Thymoma is mainly divided into two types, invasive and noninvasive type, and more than 60% of
      patients belong to noninvasive thymoma. When feasible, complete surgical resection is the
      primary treatment. There are quite a number of thymoma patients that has lost its surgical
      indications when diagnosed. Even after complete resection, the recurrence rate can be about
      20%. For patients with unresectable or recurrent disease, radiation is routinely
      administered, often in combination with systemic chemotherapy. However, because of wide range
      of radiation, more complications of conventional radiotherapy limit its treatment dose. The
      local recurrence rates of conventional radiotherapy are up 16% to 45%. Moreover, it's not
      suitable for patients with severe heart and lung disease. Stereotactic body radiation
      therapy(SBRT) well solved the problem above. On the one hand, by improving the single dose,
      it not only shortens the total radiation treatment, but also increases the total dose of
      equivalent biological effects; On the other hand, SBRT, with more precise conformal radiation
      therapy, significantly reduces the damage to the surrounding normal tissues. Theoretically,
      SBRT can improve the local control, as well greatly reduces incidence of the radiation
      pneumonia, pericarditis, tracheitis, esophagitis and so on. However, few studies focused on
      the treatment of thymoma by SBRT, except two case reports Here we performed a prospective
      study on the treatment of thymoma by SBRT. The purpose of this prospective study was a
      preliminary evaluation of feasibility, efficacy and toxicity ofγ-SBRT in the treatment of
      thymoma.
    

Intervention name(s): stereotactic body radiation therapy
Intervention type(s): Radiation
Intervention description(s): A total radiation dose of 35-50 Gy was delivered to the 50% isodose line covering at least 95% of the PTV (3.5-5Gy/fraction), and a total radiation dose of 49-70 Gy was delivered to the 70% isodose line covering at least 95% of GTV (4.9-7 Gy/fraction).
Other intervention name(s): Gamma knife
Intervention model: Sequential Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Thymoma; Thymic tumor; Stereotactic body radiotherapy