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

Treatment of persistent/recurrent nodal disease in nasopharyngeal cancer

PURPOSE OF REVIEW

Persistent or recurrent disease in the neck lymphatics is an unusual pattern of failure in nasopharyngeal carcinoma (NPC) after definitive radiotherapy or chemoradiotherapy. The purpose of this review is to critically synthesize the current knowledge regarding salvage treatment of this unique form of failure in NPC.

RECENT FINDINGS

Surgery in the form of radical neck dissection has been established as the standard salvage treatment with 5-year regional control of 60--86%. Recent shift in paradigm has resulted in the use of modified or selective neck dissection as salvage surgery in some centers. Risk factors for poor survival outcome include recurrent nodal disease, number of involved lymph nodes, extracapsular extension, high lymph node ratio, and positive resection margin. There are no well controlled studies on the role of additional radiotherapy or chemotherapy to improve local control or survival after salvage neck dissection in this group of patients with regional failure.

SUMMARY

There is limited literature regarding the extent of surgical dissection in treating nodal persistent or recurrent disease. Prospective studies are also needed to determine whether adjuvant therapy improves treatment outcomes.

Lymph-node Epstein-Barr virus concentration in diagnosing cervical lymph-node metastasis in nasopharyngeal carcinoma

PURPOSE

Cervical lymph-node (CLN) metastasis commonly occurs in patients with nasopharyngeal carcinoma (NPC) metastasis. The presence of Epstein-Barr virus (EBV) genomes in neck lymph nodes may diagnose CLN. This research was designed to appraise the diagnostic value of EBV concentration for cervical lymph nodes in NPC.

METHODS

Two hundred and fifty-three NPC patients with 276 CLNs were enrolled. MRI was performed to detect CLN metastasis, and plasma EBV concentration was measured by quantitative PCR before treatment. Ultrasonography (US) and US-FNA were subsequently performed in the suspicious lymph nodes. Fifteen patients (22 lymph nodes) underwent fine-needle aspiration cytology (FNAC), and the remaining 242 patients (254 lymph nodes) underwent core needle biopsy (CNB) for CLNs at the clinician's demand. The aspiration needle was rinsed with 1 ml of normal saline for EBV detection. The method of lymph-node EBV measurement was consistent with that for plasma. The MRI results and EBV concentrations in plasma and lymph nodes were recorded and analyzed. Plasma EBV concentrations ≥ 4000 copies/ml were regarded as positive.

RESULTS

CLN-EBV concentrations ≥ 787.5 copies/ml were regarded as positive according to receiver-operating characteristic curve analysis. The AUC of the EBV (0.925) concentration in CLN metastasis was significantly larger than the AUC of MRI (0.714) (P < 0.001). The sensitivity and specificity were 94.09% and 48.72% for MRI in lymph-node metastasis and 95.36% (P > 0.05) and 84.62% (P < 0.01) for EBV DNA in CLN metastasis, respectively. The sensitivity and specificity of EBV in plasma were 77.2% and 71.8%, respectively. The diagnostic specificity and AUC of EBV in CLNs were higher than those of MRI and plasma EBV (P < 0.005).

CONCLUSIONS

Ultrasound-guided CLN FNA to obtain EBV concentrations may provide a new method to diagnose CLN metastasis with high sensitivity and specificity.

The diagnostic and prognostic values of plasma Epstein-Barr virus DNA for residual cervical lymphadenopathy in nasopharyngeal carcinoma patients: a retrospective study

Background

Currently, the diagnosis and treatment of nasopharyngeal carcinoma (NPC) patients with residual cervical lymphadenopathy following radical radiotherapy with or without chemotherapy are challenging. We investigated the prognosis of NPC patients with residual cervical lymphadenopathy and assessed the diagnostic and prognostic values of Epstein-Barr virus (EBV) DNA in these patients.

Methods

This study included 82 NPC patients who were diagnosed with suspected residual cervical lymphadenopathy following completion of antitumor therapy. Their plasma EBV DNA levels were measured using quantitative polymerase chain reaction (qPCR) before the initiation of treatment and before neck dissection. Fine needle aspiration cytology (FNAC) was performed in 21 patients. All patients had undergone neck dissection and postoperative pathological examination to identify the nature of residual cervical lymphadenopathy. The overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS), and locoregional relapse-free survival (LRRFS) were calculated using the Kaplan–Meier method and compared using the log-rank test. The Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs). Multivariable analysis was used to estimate the effect of potential prognostic factors on survival.

Results

Following a median follow-up of 52.6 months, compared with patients with negative postoperative pathological findings for residual cervical lymphadenopathy, the patients with positive findings had a significantly lower 3-year PFS rate (49.9% vs. 83.3%, P = 0.008). Among NPC patients with residual cervical lymphadenopathy, the patients with preoperative plasma EBV DNA > 0 copy/mL had a lower 3-year PFS rate than did those with no detectable EBV DNA (43.7% vs. 61.1%, P = 0.031). In addition, combining FNAC with preoperative EBV DNA detection improved the diagnostic sensitivity. Multivariable analysis demonstrated that residual cervical lymphadenopathy with positive postoperative pathological result was an independent prognostic factor for PFS and that detectable preoperative plasma EBV DNA was an independent prognostic factor for OS.

Conclusions

Using FNAC combined with preoperative EBV DNA detection improves the sensitivity in diagnosing NPC with residual cervical lymphadenopathy. Compared with patients with undetectable EBV DNA, patients with detectable preoperative plasma EBV DNA have worse prognosis and may require a more aggressive treatment strategy.