Whole organ sectioning of mixed parotid tumors.

A pathologic study involving 15 standard formal parotidectomy specimens was carried out using the whole organ sectioning technique. Histopathologic characteristics noted included the presence of exposed capsule, breaks of the capsule, capsular incompleteness, tumor ingrowth and thickness, cellularity, and lymphocytic infiltration. Tracings of histopathology slides were used to reconstruct the three-dimensional configuration of each tumor as viewed from different angles. No tumor had a smooth surface. At the extreme, two tumor lumps were connected by just a narrow waist. Separated tumors were not seen. In only one specimen did a lymph node contain an additional tumor in the form of an adenolymphoma. All tumors showed some exposed capsule or "bare area" to a degree affected mainly by the position of the tumor. Capsular damage was occasionally seen and was usually minor. Capsular incompleteness and tumor ingrowth make global capsular dissection unsafe. It is concluded that formal parotidectomy remains the operation of choice for pleomorphic adenoma of the parotid gland, although capsular dissection (otherwise termed enucleation) cannot be entirely avoided during the procedure.