2.2 Inclusion and exclusion criteria
The inclusion criteria were as follows: (1) NPC confirmed by pathology;
(2) relapse after EBRT and unable or rejecting to undergo surgery or
re-irradiation; (3) tumor diameter ≤7cm; (4)pre-plan shown a feasible
needle pathway to avoid bones, large blood vessels or organs at risk
(OARs); (5) Karnofsky Performance Status (KPS) ≥60; (6) expected
survival ≥3 months. The exclusion criteria were as follows: (1) severe
bleeding tendency; (2) immunocompromised with acute infection or chronic
active infection; (3) patient with conditions intolerant to minimal
invasive procedure/surgery such as severe cardiopulmonary insufficiency
or liver and kidney; (4) contraindication to anesthesia; (5)
uncontrolled multiple metastases.