Evaluation of the VX2 rabbit auricle carcinoma as a model for head and neck cancer in humans.
BACKGROUND
This study investigates whether the VX2 carcinoma cell line, transplanted into the rabbit auricle, can be used as a head and neck cancer model. The biologic behaviour of this model is evaluated, comparing tumour transplantation with either tissue pieces or cell suspensions.


METHODS
Thirty-six adult NZW rabbits received s.c. injections of VX2-suspensions (Group S) and 11 rabbits received solid VX2-pieces (Group P) into both auricles.


METHODS
In Group S, 16 rabbits were sacrificed at various days before (S1) and 15 after (S2) the 28th day following transplantation. In the other five rabbits transplantation failed. Animals from Group P were sacrificed every 2 weeks after the 28th day. At autopsy the size of the primary tumours and of lymph node, lung and other metastases were assessed. If transplantation failed, the maximal tumour size and the time at which regression took place were recorded. Exponential trend lines were used to create growth curves of metastases. Differences between groups were evaluated with the chi2 test, correlations between parameters with Kendall's tau.


RESULTS
The tumour take-rate in Groups S and P was 78% and 59% respectively. The maximal size and time at which regression occurred was significantly different, amounting to 83 +/- 7 mm2 at 10.4 +/- 1.6 days (Group S) and 243 +/- 30 mm2 at 20.9 +/- 2.0 days (Group P), respectively. Development of lymph node metastases was not different. In Groups P and S2, over 90% of the necks contained lymph node metastases. There was a higher incidence of lung metastases in Group S2 when compared to Group P (47% vs. 14%) but it was not statistically significant. A significant correlation (p<0.05) between weight loss and the size of lung metastases was found.


CONCLUSIONS
Transplantation of the VX2-tumour with cell suspensions produces a useful head and neck cancer model for locoregional disease in which anti-tumour regimens against both the primary and lymph node metastases can be tested. Transplantation with tumour pieces is not advised as the take-rate is low and spontaneous remissions occur at a late stage.
van Es
R J
RJ
Department of Oral and Maxillofacial Surgery, University Medical Centre Utrecht, The Netherlands. omfsurg@kmb.azu.nl
Dullens
H F
HF
van der Bilt
A
A
Koole
R
R
Slootweg
P J
PJ
D000818:Animals; D002277:Carcinoma / Q000473:pathology* / Q000556:secondary; D016009:Chi-Square Distribution; D004195:Disease Models, Animal; D004428:Ear Neoplasms / Q000473:pathology; D004431:Ear, External; D005260:Female; D006258:Head and Neck Neoplasms / Q000473:pathology*; D006801:Humans; D015994:Incidence; D007279:Injections, Subcutaneous; D008175:Lung Neoplasms / Q000473:pathology / Q000556:secondary; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis / Q000473:pathology; D009365:Neoplasm Regression, Spontaneous; D009368:Neoplasm Transplantation / Q000379:methods; D011817:Rabbits; D013223:Statistics as Topic; D014407:Tumor Cells, Cultured; D015431:Weight Loss