Natural course and tumor doubling time of nasopharyngeal carcinoma. A study of 15 patients

Focal Nasopharyngeal Activity Detected on [18F]FDG PET/CT: Clinical Implications and Comparison of Metabolic Parameters for Prediction of Malignancy

Purpose

We aimed to investigate the incidence and clinical significance of incidental focal nasopharyngeal uptake on [18F]FDG PET/CT and to evaluate the diagnostic performance of various metabolic parameters to differentiate between benign and malignant nasopharyngeal lesions.

Methods

A total of 63 consecutive patients with incidental focal nasopharyngeal uptake on [18F]FDG PET/CT and subsequent nasopharyngeal biopsy were retrospectively enrolled. In addition, baseline pretherapeutic [18F]FDG PET/CT images of 59 patients with newly diagnosed pathologically proven nasopharyngeal carcinoma (NPC) were reviewed. Maximum standardized uptake value (SUVmax), mean SUV (SUVmean), nasopharynx-to-palatine tonsil ratio (NPR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the nasopharyngeal lesions were determined. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance of the metabolic parameters.

Results

Incidental focal nasopharyngeal uptake in two patients (3.2%, 2/63) was pathologically confirmed to be NPC. All the metabolic parameters (SUVmax, SUVmean, NPR, MTV, and TLG) demonstrated significantly greater values in patients with NPC compared with patients with benign or physiological nasopharyngeal uptake (p < 0.001). Among the metabolic parameters, NPR demonstrated the greatest area under the curve of 0.992 (p < 0.05), with a sensitivity of 96.7% and a specificity of 93.4% when a cut-off of 1.1 was used. Similar results were seen in nasopharyngeal lesions without morphological abnormality.

Conclusion

NPC is an infrequent but important cause of incidental focal nasopharyngeal uptake on [18F]FDG PET/CT. Metabolic parameters were shown to be useful to differentiate between benign and malignant nasopharyngeal lesions, and NPR showed the best diagnostic performance.

Clinical Characteristics and Predictive Outcomes of Recurrent Nasopharyngeal Carcinoma-A Lingering Pitfall of the Long Latency

Purpose: To investigate the clinical characteristics, risk factors, and clinical outcomes of long-latent recurrence (>five years) of nasopharyngeal carcinoma (NPC). Methods: This retrospective study enrolled newly diagnosed NPC patients from the Chang Gung Research Database between January 2007 and December 2019. We analyzed the patients’ characteristics and survival outcomes after recurrence. Results: A total of 2599 NPC patients were enrolled. The overall recurrence rate was 20.5%, while 8.1% of patients had long-latent recurrence (>five years). These patients had a higher percentage of initial AJCC (The American Joint Committee on Cancer) stage I/II (60.5%, p = 0.001) and local recurrence (46.5%, p < 0.001). Unresectable rT3 and rT4 were found in 60% of patients when recurrence and 30% of local recurrence occurred in the skull base, which could not be detected by the regular endoscopy. The five-year overall survival rate of long-latent recurrence was 19.7%. Alive patients tended to be asymptomatic but have regular follow-ups with the interval less than six months. Multivariate analysis showed age and initial advanced AJCC stages were independent risk factors of death after recurrence. In contrast, patients with recurrence between two and five years, salvage surgeries, and regional recurrence had favorable survival outcomes. Conclusion: Long-latent NPC recurrence is not rare, and the survival outcome is poor. Regular follow-up for early detection of NPC recurrence is necessary even after five years of disease-free period.

Survival impact of increasing time to IMRT initiation following induction chemotherapy in nasopharyngeal carcinoma: A propensity score-matched analysis

PURPOSE

To explore the prognostic impact of waiting time for radiotherapy (RT) after induction chemotherapy (IC) for nasopharyngeal carcinoma (NPC).

METHODS AND MATERIALS

A total of 648 NPC patients receiving IC between 2009 and 2011 were included. Propensity score matching (PSM) was performed to balance the variables. Survival outcomes were compared in subgroups based on time to RT (TTR) after IC.

RESULTS

The optimal cutoff point for TTR was 28 days. A total of 330 patients were selected by 1:2 PSM. Stratified and dichotomized TTRs were both strongly correlated with prognosis. Patients with TTR > 28 days had significantly worse 5-year LRFS, DMFS, DFS and OS than those with TTR ≤ 28 days (P < 0.05). In multivariate analysis, TTR > 28 days was an independent predictor of worse LRFS [HR=2.08; 95% CI, 1.18-3.66; P = 0.011), DMFS (HR=1.65; 95% CI, 1.04-2.62; P = 0.033), DFS (HR=1.86; 95% CI, 1.35-2.62; P < 0.001) and OS (HR=1.90; 95% CI, 1.26-2.85; P < 0.001). High-risk patients with T4 or N2-3 disease were highly susceptible to RT delay with impaired DFS and OS. In high-risk patients with TTR > 28 days, concurrent chemotherapy yielded better DMFS (70.9% vs. 52.0%, P  =  0.041), DFS (52.5% vs. 34.3%, P = 0.039) and OS (70.3% vs. 53.2%, P = 0.048).

CONCLUSIONS

Prolonged waiting is detrimental to survival in NPC, and it is strongly recommended to start RT within 28 days after IC. T4/N2-3 NPC has a higher risk of treatment failure with delayed RT. With potential protection against RT delay, concurrent chemotherapy should be performed in high-risk patients as salvage therapy.

A prospective study: current problems in radiotherapy for nasopharyngeal carcinoma in yogyakarta, indonesia

Introduction

Nasopharyngeal carcinoma (NPC) has a high incidence in Indonesia. Previous study in Yogyakarta revealed a complete response of 29% and a median overall survival of less than 2 years. These poor treatment outcome are influenced by the long diagnose-to-treatment interval to radiotherapy (DTI) and the extended overall treatment time of radiotherapy (OTT). This study reveals insight why the OTT and DTI are prolonged.

Method

All patients treated with curative intent radiotherapy for NPC between July 2011 until October 2012 were included. During radiotherapy a daily diary was kept, containing information on DTI, missed radiotherapy days, the reason for missing and length of OTT.

Results

Sixty-eight patients were included. The median DTI was 106 days (95% CI: 98−170). Fifty-nine patients (87%) finished the treatment. The median OTT for radiotherapy was 57 days (95% CI: 57–65). The main reason for missing days was an inoperative radiotherapy machine (36%). Other reasons were patient’s poor condition (21%), public holidays (14%), adjustment of the radiation field (7%), power blackout (3%), inoperative treatment planning system (2%) and patient related reasons (9%). Patient’s insurance type was correlated to DTI in disadvantage for poor people.

Conclusion

Yogyakarta has a lack of sufficient radiotherapy units which causes a delay of 3–4 months, besides the OTT is extended by 10–12 days. This influences treatment outcome to a great extend. The best solution would be creating sufficient radiotherapy units and better management in health care for poor patients. The growing economy in Indonesia will expectantly in time enable these solutions, but in the meantime solutions are needed. Solutions can consist of radiation outside office hours, better maintenance of the facilities and more effort from patient, doctor and nurse to finish treatment in time. These results are valuable when improving cancer care in low and middle income countries.