Postoperative radiation for XXXX metastatic to cervical lymph nodes from an unknown primary site: outcomes and patterns of failure.

@entity1 @entity135 @entity66 @entity5 @entity957 @entity1544 @entity1442
BACKGROUND: This retrospective study assesses the outcomes and patterns of failure in @entity1 with @entity957 metastatic to cervical lymph nodes from an unknown primary site treated with combined surgery and postoperative radiotherapy. METHODS: One hundred thirty-six @entity1 with @entity957 metastatic to cervical lymph nodes from an unknown primary source were treated postoperatively with radiotherapy at the University of Texas M. D. Anderson @entity5 Center between the years 1968 and 1992. Stage distribution was: N1, 31 @entity1 ; N2a, 49; N2b, 25; N2c, 3; N3, 18; and Nx, 10. Thirty-nine @entity1 had excisional biopsies only, 64 @entity1 underwent modified neck dissections, and 33 had radical neck dissections. Extracapsular extension was present in 87 cases. Fifty-nine @entity1 had multiple nodes involved. The median duration of follow-up for surviving @entity1 was 8.7 years. RESULTS: Twelve @entity1 , all with extracapsular @entity66 , developed regional relapse. The 5-year actuarial rates of regional relapse in @entity1 with and without extracapsular @entity66 were 16% and 0%, respectively (p = .004). Nine @entity1 (22%) with @entity66 and multiple nodes relapsed compared with three @entity1 (7%) with @entity66 and a solitary node (p = .02). None of the @entity1 treated with excisional biopsy and radiotherapy relapsed regionally. No statistically significant relationship between dose, treatment duration, time interval between surgery, and the start of radiotherapy and relapse was detected. The 2-, 5-, and 10-year actuarial disease-specific survival rates were 82%, 74%, and 68%, respectively. Fourteen @entity1 developed @entity5 in @entity135 ; six of these @entity5 were located in unirradiated tissues. CONCLUSIONS: Relapse occurred infrequently in @entity1 treated with excisional biopsies and postoperative radiotherapy. Extracapsular extension and multiple nodes were associated with worse regional control and disease-specific survival. These results appear consistent with those expected for @entity1 with @entity1442 and a known primary site, and the absence of a primary site should not exclude @entity1 from studies aiming to improve outcomes in @entity1 with @entity135 from a head and neck @entity1544 . We continue to recommend radiation to the necks and pharyngeal axis for @entity1 suspected of having residual microscopic disease following surgery for @entity957 metastatic to the neck from an unknown primary site.
