Evaluation of recurrent nodal disease after definitive radiation therapy for nasopharyngeal carcinoma: Diagnostic value of fine‐needle aspiration cytology and CT scan

Abstract

Radiological imaging and FNAC are useful diagnostic modalities in assessing recurrent nodal disease in the post-irradiated neck in patients with NPC. Although routine CT scan criteria for pathologic lymphadenopathy cannot be accurately applied in the post-irradiated neck, it is a useful surveillance tool in the routine follow-up of patients with post-irradiated neck with NPC. Clinicians, however, must understand their limitations when assessing these patients. The possibility of negative neck dissection must be conveyed to the patients.

Residual cervical lymphadenopathy after definitive treatment of nasopharyngeal carcinoma: fine needle aspiration cytology, computed tomography and histopathological findings

“…In our previously published study on recurrent nodal disease, CT scanning had a positive predictive value of 78.6 per cent and a negative predictive value of 20 per cent for multilevel lymph node involvement. 12 The final pathological neck dissection specimen showed more nodal involvement than was radiologically evident. 12 These findings mirror reports by other investigators.…”

“…12 The final pathological neck dissection specimen showed more nodal involvement than was radiologically evident. 12 These findings mirror reports by other investigators. 6,9,16,17 High resolution ultrasound (US) is reported to be more sensitive than clinical examination (92 per cent versus 70 per cent) in detecting and differentiating benign from malignant nodes.…”

“…In a separately published study, we reported a 10.8 per cent negative neck dissection rate for 42 patients presenting with recurrent nodal disease. 12 Other studies combining patients with residual and recurrent disease in their analysis have reported negative neck dissection rates of 4-12 per cent. 8,9 There is no standardised time-frame for observing residual lymph nodes before instituting treatment.…”

“…9 In a separate study, we published data on 42 patients presenting with suspected recurrent cervical nodal disease; we found a sensitivity, specificity, positive predictive value and negative predictive value of 75, 75, 93.8 and 37.5 per cent, respectively, for the use of FNAC to identify disease. 12 Rates as low as 57 per cent have been reported for the sensitivity of FNAC to detect recurrent nodal disease. 7 Whether FNAC is needed in the first place, or should be repeated if negative, is controversial.…”

Sonographic Examination of the Neck after Definitive Radiotherapy for Node-Positive Oropharyngeal Cancer

“…33 A study from Singapore found a higher PPV and NPV for US over CT in the evaluation of recurrent nodal adenopathy from nasopharyngeal cancer. 34 However, legitimate concerns have been raised about performance of US of the neck after RT as an inaccurate and overly formidable technical undertaking. One common belief is that fibrosis in the neck limits examination and makes FNAC samples overly difficult to obtain, and another is that either due to sampling error or idiosyncratically responding nodes at varying stages of posttreatment viability, reliable results are unlikely.…”