Predicting distant failure in nasopharyngeal cancer.
In a prospective study of 78 patients with nasopharyngeal cancer, we examined the prognostic significance of T stage, histology, parapharyngeal involvement, and lymph node dimensions, size, and level concerning distant metastasis. AU patients were treated with radical radiotherapy alone and completed 3 to 7 years of follow-up. In univariate analysis of time to metastasis, there was a significant difference stratifying for T stage (T1 and 2 versus T3 and 4), node dimensions (less than 6 versus more than or equal to 6 cm), neck level (above versus below the thyroid notch), and parapharyngeal involvement, but not for bilaterality of lymphadenopathy. Histology was an important prognostic factor related to distant metastasis since none of the 24 World Health Organization class I cases showed distant metastasis versus 14 (26%) of 54 patients with World Health Organization class II/III carcinoma. A multivariate duration model of time to metastasis within the later histologic group suggested that lymph node dimensions, node level, and T stage were the most important factors related to distant metastases, with the hazard ratios being 3.98, 3.23, and 1.76, respectively. Multivariate analysis within the T3- to T4-stage group showed that node dimension was the only significant variable, with an associated hazard ratio of 4.09. Cases with upper-neck lymphadenopathy and node dimensions of less than 6 cm had a distant metastasis rate of <5%. We conclude that adjuvant chemotherapy for nasopharyngeal cancer is justified in T3- and T4-staged cases with nonkeratinizing or undifferentiated histology and with lymph nodes larger than 6 cm and/or located below the thyroid notch.
Koukourakis
M I
MI
Department of Radiotherapy and Oncology, University Hospital of Iraklion, Crete, Greece.
Whitehouse
R M
RM
Giatromanolaki
A
A
Saunders
M
M
Kaklamanis
L
L
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009303:Nasopharyngeal Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D011879:Radiotherapy Dosage; D015996:Survival Rate; D017211:Treatment Failure