A Clinical Study on Distant Metastasis of Oral Squamous Cell Carcinomas
The recent advance in cancer treatment has improved loco-regional control of oral squamous cell carcinomas (OSCC). On the other hand, unfavorable outcome due to distance metastasis becomes an important issue in OSCC treatment. The purpose of this study is to summarize clinical characteristics of OSCC patients with distance metastases.
Subjects and methods
A retrospective study was carried out with a sample of OSCC patients who met the following criteria : 1) no primary cancers of other organs except for the oral cavity were noted, and 2) distant metastasis was diagnosed by imaging examinations. Out of 559 OSCC patients who were treated at our department between 1981 and 2013, 21 patients were retrieved for this study.
Results
Twenty-one patients consisted of 13 men and 8 women. The age at the first visit ranged from 17 to 83 years old. Primary site was tongue in 12 cases, mandibular gingiva in 4, floor of mouth in 2 and buccal mucosa, maxillary gingiva and maxillary sinus in 1. Clinical staging was classified as Stage I in 3 cases, Stage II in 3, Stage III in 3 and Stage IV in 12. Histopathological examination showed OSCC in 20 cases and basaloid squamous cell carcinoma (BSCC) in 1. The organ of distant metastasis was lung in 19 cases, bone in 5, mediastinal lymph node in 5, blain in 3, skin in 3 and liver in 1. Fourteen cases had distant metastases of a single organ and 7 cases had those of multiple organs. When the diagnosis of distant metastasis was made, 9 cases had no recurrent lesions loco-regionally, and meanwhile 12 cases had recurrence. When compared the patients with loco-regional control and those with loco-regional recurrence, the median time until the appearance of distant metastasis was 6 months and 15 days (range 26 days - 22 months and 29 days) in the control cases, and 3 months (range 0 day - 9 months and 19 days) in the uncontrol cases. There was a tendency that the period to distant metastasis appearance was longer in the control cases. However, there were 3 cases which showed early distant metastasis within 3 months after loco-regional treatments; this suggested the existence of a subtype of OSCC, which easily occurred hematogenous metastasis. About gender, age, primary site and clinical staging, there were no differences between the control and the uncontrol cases. Cervical lymph node metastasis was observed before distant metastasis in 20 cases except for the BSCC case. Furthermore, there was no relationship between chemotherapy regimens and the period to distant metastasis appearance. Twenty cases, except for the BSCC case, took the outcome of death.
Conclusion
Further studies are needed to search risk factors of distant metastasis to improve the survival of OSCC patients.
References
Minoru T et al : Causes of Oral Tongue Cancer Treatment Failures. CANCER March 2,2992, Volume 69, No. 5
Waseem Jerjes et al : Clinicopathological parameters, recurrence, locoregional and distant metastasis in 115 T1-T2 oral squamous cell carcinoma patients. Head & Neck Oncology 2010, 2:9