I would use "plump"

Histologic Findings: The granular cell tumor is characterized by the presence of sheets or clusters of plump cells with a granular cytoplasm. These lesions are not circumscribed and often come into intimate contact with the overlying surface squamous epithelium. A frequent finding is pseudoepitheliomatous hyperplasia of the overlying epithelial layer. These cells generally are uniform and do not exhibit significant atypical features. Malignant granular cell tumors, which fortunately are rare, may have a very benign histologic appearance. Tumor cells more or less stain uniformly positive for S-100 protein, neuron-specific enolase, CD68, and PGP9.5.
http://www.emedicine.com/derm/topic672.htm

The tumor was composed of spindle-shaped and plump cells embedded in dense collagenous stroma. The tumor cells were arranged in interlacing fascicles or in a patternless pattern.
http://arpa.allenpress.com/arpaonline/?request=get-document&...

The untreated R3327-H tumor had acini of varying sizes and shapes with moderately plump cells whose cytoplasm were slightly hyperchromatic.
http://www.jurology.com/pt/re/juro/fulltext.00005392-1998120...