Assessment of murine lung tumour development: a comparison of two techniques.

Two techniques (surface photographic analysis [SPA] and microscopic tumour analysis [MTA]) are described for assessing the stage of tumour development induced by intraperitoneal 4-(methyl nitrosamino)- 1-(3 pyridyl)-1-butanone in syngeneic A/J mice. Parameters used to assess the number and size of tumours were surface tumour count (STC), surface tumour area (STA). and relative tumour surface area (RTSA)--all using SPA; and mean tumour count (MTC), mean tumour area, and relative tumour area (RTA)--all using MTA. In a study examining the possible effects of Millipore chamber implantation on lung tumours, the stage of tumour development was assessed in 239 mice using both SPA and MTA. Statistically significant correlations (Spearman-Rank) were apparent between the derived parameters: STC vs. MTC (r = 0.6, P <0.0001); STA vs. mean tumour area (r = 0.5, P <0.0001); RTSA vs. RTA (r = 0.4, P <0.0001). Therefore, it is concluded that SPA--the simpler technique--is an appropriate method for assessing the stage of tumour development in this model.