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[Regional failure of hypopharyngeal squamous cell carcinoma].

PURPOSE
Lymph nodes and distant metastases contribute to the poor prognosis of hypopharyngeal squamous cell carcinoma. The purpose of this study is to estimate the frequency, mode and prognosis factors related to regional and distant metastasis.


PATIENTS AND METHOD
The authors' report is based on a retrospective study concerning 271 hypopharyngeal squamous cell carcinoma, compiled in the service of Surgery of Head and Neck Cancers of the Salah-Azaïz Institute (1977-2002). Frequency and histoclinical characters of cervical and distant metastases have been assessed, as well as their prognosis factors among 155 patients treated in a curative purpose.


RESULTS
39.1% of the tumours were classified N0, 24.4% N1, 10.7% N2 and 25.8% N3 (UICC 2002). The cervical nodal invasion was significantly more frequent for the classified tumors T3T4 than for the T1T2 (for pyriform sinus, postcricoid esophagus, posterior wall, and total hypopharynx, respectively : P =0.001, P =0.007, P =0.047 and P =0.0005). A cervical lymphatic evidement was preferred in thirty two patients. Among N0, 46.9% were N+; The frequencies of the capsular effraction were not significantly different for the N0N1 from for the N2N3 (P =0.11). The two and five years survival rates were respectively 32.5 and 20.5% for N0, and 10.9% and zero for N3. The survival differences after two and five years between the N0N1 and the N2N3 were significant (P =0.04). A regional failure was noticed for 18.5% of the patients. The tumoral site did not influence significantly the rate of nodal failure (P =0.98), neither the clinical status N (P =0.34). Capsular effraction was a significant factor for the regional failure (P =0.007). Distant metastasis significantly occurred more frequently among the patients initially classified N2N3 than those classified N0N1 (P =0.03), and in case of capsular effraction (P =0.0009).


CONCLUSION
Hypopharyngeal squamous cell carcinoma has a high rate of lymph nodes metastasis, correlated to the local extension, and a high rate of occult nodal metastasis. Lymph node clinical status does not seem to have influenced the patients survival; however, capsular effraction constitutes a major prognosis factor of regional failure and distant metastasis. Distant metastases are frequent, particularly in case of wide local and regional tumoral extension.