[A correlation between metastasis and histopathological differentiation in patients with carcinoma of the nasal cavity and paranasal sinuses].

The aim of this retrospective study was to investigate a correlation between histopathological differentiation and metastasis in patients with carcinoma of the nasal cavity and paranasal sinuses to improve the survival. Between 1984 and 1992, 52 cases of sino-nasal malignant tumors were treated at Kagawa Medical School Hospital. Squamous cell carcinoma was evaluated in 29 patients and undifferentiated carcinoma in five patients. Treatment in most cases consisted of radiotherapy, 50 Gy/25 fr/5 weeks, continuous intra-arterial infusion of 5-FU 2000 mg/4 weeks, and an extensive Denker's operation 2-3 weeks after the completion of radiotherapy. The 5-year survival rate was 53%, and the local control rate was 82%. Patients died of local failure (six), distant metastases (six), lymph node metastases (one) and other causes (three). Twenty-eight patients with local control were classified into G1-2 (well- and moderately-differentiated) and G3-4 (poorly-differentiated and undifferentiated) groups. Lymph node metastasis was unrelated to the degree of differentiation, but distant metastasis was significantly correlated to the degree of differentiation (P = 0.014). The 5-year survival rates in lymph node metastasis (n = 7), non-lymph node metastasis (n = 21), distant metastasis (n = 7), non-distant metastasis (n = 21), and the G1-2 (n = 17) group and the G3-4 group (n = 11) with local control were 57%, 63%, 14%, 78% (P = 0.002), 72% and 44% (P = 0.0384), respectively. The results of combination therapy were poor in patients with poorly-differentiated or undifferentiated carcinoma because of distant metastasis, and adjuvant chemotherapy may be necessary in such patients to prevent distant metastasis.