Prognostic significance of parapharyngeal space venous plexus and marrow involvement: potential landmarks of dissemination for stage I-III nasopharyngeal carcinoma.
OBJECTIVE
To determine whether the parapharyngeal space venous plexus and marrow of the skull base bones are anatomic landmarks of the potential routes for the spread of disease for Stage I-III (American Joint Commission on Cancer 1997 staging system) nasopharyngeal carcinoma (NPC).


METHODS
A total of 364 patients with NPC were enrolled in this study. The selection criteria were Stage I-III disease and primary radiotherapy at our hospital between 1990 and 2001. All patients had undergone MRI to evaluate the head-and-neck tumors. Patients who had undergone inadequate radiotherapy at a dose of <60 Gy and/or preradiotherapy chemotherapy before the imaging evaluation were excluded from the study.


RESULTS
Of the 364 patients treated between 1990 and 2001, 163 (44.8%) had low-risk Stage I-III NPC (without parapharyngeal space extension or T3 disease). The 5-year distant metastasis-free survival rate, with and without adjuvant chemotherapy, was 97% and 96%, respectively. The remaining 201 patients had Stage II-III with parapharyngeal space extension or T3 disease. Their 5-year recurrence-free survival rate, with and without adjuvant chemotherapy, was 76.8% and 53.2% (p = 0.01), respectively.


CONCLUSIONS
Our findings suggest that the risk of distant metastasis in Stage I-III NPC patients without parapharyngeal space extension or T3 disease is extremely low. Invasion into the parapharyngeal space venous plexus and marrow of the skull base bones is associated with distant metastasis, and involvement of these anatomic sites is considered a potential route for hematogenous disease spread in patients with Stage I-III NPC.
Cheng
Skye Hongiun
SH
Department of Radiation Oncology, Koo Foundation Sun Yat-Sen Cancer Center, Taipei, Taiwan. skye@mail.kfcc.org.tw
Tsai
Stella Y C
SY
Yen
K Lawrence
KL
Jian
James Jer-Min
JJ
Feng
An-Chen
AC
Chan
Kwan-Yee
KY
Hong
Cheng-Fang
CF
Chu
Nei-Min
NM
Lin
Yen-Chun
YC
Lin
Chin-Yen
CY
Tan
Tran-Der
TD
Hsieh
Cheng-Yee
CY
Chong
Vincent
V
Huang
Andrew T
AT
D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D017024:Chemotherapy, Adjuvant; D002945:Cisplatin / Q000008:administration & dosage; D005260:Female; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000188:drug therapy* / Q000473:pathology / Q000532:radiotherapy*; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis / Q000517:prevention & control; D009367:Neoplasm Staging; D010614:Pharynx; D017410:Practice Guidelines as Topic; D011379:Prognosis; D016016:Proportional Hazards Models; D015996:Survival Rate; D017211:Treatment Failure
D002945:Cisplatin; D005472:Fluorouracil