A PAS stain or immunostain for type IV collagen will help demonstrate the absence of basal lamina. The features in the table below highlight the differences between tubular carcinoma and other benign entities which may be confused with a carcinoma. The tubular pattern should be present throughout the tumor for a designation of pure tubular carcinoma. Tubular carcinoma rarely involves more than 1 low axillary node. When axillary node metastases occur, the tubular pattern is retained.
Tubular carcinomas have an excellent prognosis and are ideally suited for conservative therapy.
Even with lymph node metastases the survival for pure tubular carcinoma is significantly better than that of infiltrating ductal carcinoma. The mixed variant also has a better prognosis than infiltrating ductal carcinoma, although it is not as good as for pure tubular carcinomas.