Release: July 29, 2000
Contact: Kenneth Satterfield
703-519-1563
[email protected]
In San Francisco (7/28-8/2)
415-284-8082
PREDICTORS OF DISTANT METASTASIS FROM HEAD AND NECK CANCER ARE IDENTIFIED, MAY IMPROVE OUTCOME
San Francisco, CA-- A new study identifies several clinical and pathologic criteria associated with distant metastasis (DM). This is the first study with lengthy follow-up data and large patient population to correlate these prognostic factors to rates of distant metastasis in head and neck squamous cell carcinoma (HNSCC).
Distant metastasis in HNSCC is an ominous development, since there is no effective therapy currently available. Systemic therapy directed at microscopic disease may however be of benefit in decreasing the rate of DM and thereby improve disease-free survival. This study provides a panel of clinical and histopathologic predictors that may identify patients at the greatest risk for development of DM.
The authors of the study, "Clinicopathologic Predictors of Distant Metastases from Head and Neck Squamous Cell Carcinoma" are F. Christopher Holsinger MD, Robert M. Byers, MD, Dianna B. Roberts PhD, Pat F. Wolf, Jeffrey N. Myers, MD PhD, all from the Department of Head and Neck Surgery, University of Texas M.D. Anderson Cancer Center, in Houston, TX. The findings were presented before the 5th International Conference on Head and Neck Cancer, being held July 29 through August 2, at the San Francisco Marriott, San Francisco, CA. More than 1,500 leading head and neck surgeons from the United States and 46 nations will gather to hear the latest medical research in the diagnosis, treatment, and reconstruction associated with head and neck cancer. The medical conference is sponsored by the American Head and Neck Society, www.headandneckcancer.org.
Methodology: The research team viewed two separate databases from the M.D. Anderson Cancer Center (1970-1979, 601 patients; 1985-1989, 520 patients). A model was developed to predict the incidence of Distant Metastases (DM) for head and neck cancer patients. The pilot data suggested that T stage greater than 3, N stage greater than 2, and a pharyngeal primary (oropharynx or hypopharynx) are associated with significantly increased risk for distant metastases.
To test this hypothesis, 650 consecutive patients with HNSCC (head and neck squamous cell carcinoma) were identified in a period from May 31, 1991 to March 31, 1994. Clinical data included demographic factors (age, gender, and race) as well as tumor site and staging. Tumors were staged based on clinical examination using the American Joint Committee on Cancer (AJCC) 1988 and 1992 staging system. Tumor site was classified as hypopharynx, larynx, oral cavity, and oropharynx. Patients with primary tumors of the nasopharynx and paranasal sinuses were excluded from the review.
Histopathologic data were recorded. The surgical pathology report for the initial biopsy and/or definitive resection was reviewed and assessed for degree of differentiation, depth of invasion (where applicable), lymphatic invasion, vascular invasion, perineural invasion, DNA aneuploidy, and extracapsular invasion. Data from each neck dissection specimen was collected. Detailed treatment
information included the extent of surgical resection and method of reconstruction. Total radiation therapy dose and treatment interval were recorded. For patients receiving chemotherapy, the number of cycles, the particular agents used, and the type (induction, concomitant, vs. boost) of chemotherapy was noted. These patients were followed prospectively for these outcomes: 5-year survival and local, regional, and distant relapse.
Results: In this study, the five-year incidence of distant metastasis was 15 percent (94/622). Other key findings included:
Pulmonary metastases were most commonly found: 62 to the lung, 4 to the mediastinum, 2 to the pleura. Metastases to bone (21) and to the liver (9) were the next most commonly encountered. Thirty (31.9%) of patients with DM presented with more than one metastatic site. Lung was the most common site for solitary metastasis. The most common site for bony metastasis was the spine (12), followed by skull(4), then rib(3), and axial bones (femur, humerus; 2). More than half of patients with osseous metastases presented with multiple sites.
Of 213 patients with oral cavity SCC, 33 (15 percent) developed DM; 26 of 146 (18 percent) patients with oropharyngeal SCC, 21 of 194 (11 percent) patients with laryngeal SCC, and 14 of 69 (20 percent) patients with hypopharyngeal SCC developed DM.
Disease stage showed a striking correlation with the risk for DM: stage I, 1 percent; stage II, 14 percent; stage III, 15 percent; stage IV, 20 percent (p less than 0.0003). Advanced disease (T stage greater than 3 and N stage greater than 2a) was significantly correlated statistically with the development of DM (p less than 0.003). We found that certain clinical features (extent of cervical metastasis or N stage) and histopathologic data (evidence of lymphatic or vascular invasion and extension beyond the confines of the lymph node) are associated with significantly increased rates of DM.
Conclusions: The five-year incidence of distant metastasis is 15 percent. This study provides a panel of clinical (N-stage) and histopathologic predictors (extracapsular invasion, lymphovascular invasion) that may identify patients at the greatest risk for development of DM. Based on this research, patients could be identified and received systemic chemotherapy that may prevent the development of this fatal disease--before it develops. This could be an important step forward and improved the overall outcome and survival in head and neck cancer.
- end -
For additional information regarding head and neck cancer, log on to http://www.entnet.org/cancer.html
RSS