Role of cyclooxygenase-2 in tumor progression and survival of head and neck squamous cell carcinoma

Inhibition of cyclooxygenase-2 (COX-2) pathways may have significant implications for the prevention and treatment of head and neck squamous cell carcinoma (HNSCC). COX-2 is overexpressed in both premalignant lesions and invasive HNSCC. We examined COX-2 expression by immunohistochemistry in normal tissues, different stages of premalignant lesions, and carcinoma in situ (CIS). We also evaluated the correlation between COX-2 expression and clinical characteristics of HNSCC patients. Tissue specimens were obtained from the following: premalignant lesions from 25 subjects enrolled in a biochemoprevention trial, tumor samples collected at diagnosis from 38 HNSCC patients enrolled in an induction chemotherapy trial, and normal control tissues from 10 noncancer, nonsmoking subjects. COX-2 was expressed in early and intermediate stages of premalignant lesions, increasing first in the basal and parabasal layers, then lower spinous, and upper spinous layers. This correlation was noted in normal epithelium (P < 0.0001), histologically normal in-field samples (P < 0.0001), low-grade dysplasia (P = 0.024), and moderate-grade dysplasia (P = 0.009), but was lost in the majority of high-grade dysplasia/CIS (P = 0.896). COX-2 expression was also noted to increase progressively through the early stages of premalignancy, and to decrease in severe/CIS stage and invasive carcinoma. COX-2 expression in tumors from patients treated with induction chemotherapy was correlated with overall survival after controlling for clinical variables. These findings elucidate the differential expression pattern of COX-2 in stages of head and neck premalignant lesions and invasive carcinoma, supporting the rationale for COX-2 inhibition as an important strategy for cancer chemoprevention. Further validation of COX-2 expression is needed in prospective ongoing chemoprevention trials.

The role of taxanes and targeted therapies in locally advanced head and neck cancer

PURPOSE OF REVIEW

This review presents new data on the role of taxanes and targeted therapies in the management of squamous cell carcinoma of the head and neck.

RECENT FINDINGS

Taxane-containing triplets are clearly superior as an induction regimen in locally advanced squamous cell carcinoma of the head and neck when compared with cisplatin/5 fluorouracil which has been the standard for two decades. Preliminary data suggest that the addition of a taxane to cisplatin/5 fluorouracil as induction regimen followed by chemoradiation may be superior to chemoradiation alone. The addition of cetuximab to radiation prolongs locoregional control and survival without increasing mucositis. Areas of active investigation are the search for epidermal growth factor receptor mutations and the optimal way of integrating epidermal growth factor receptor-directed therapies into standard management. Meanwhile new targets are explored.

SUMMARY

Taxane/cisplatin/5 fluorouracil induction chemotherapy is clearly superior to cisplatin/5 fluorouracil. Epidermal growth factor receptor directed therapies can safely be combined with radiation and the combination shows encouraging results.