WASHINGTON, March 7 (Reuters) - Bostwick Laboratories Inc, a specialized anatomic pathology laboratory focused on the diagnosis of cancer, said on Friday it is planning an initial public offering of as much as $100 million in common stock.

Banc of America Securities LLC, Wachovia Securities, William Blair & Co, and Cowen & Co will underwrite the IPO, according to a preliminary offering document filed with the U.S. Securities and Exchange Commission.

The Glen Allen, Virginia-based company is seeking a Nasdaq listing under the symbol "BOST" (BOST.O: Quote, Profile, Research).

(Reporting by John Poirier, editing by Richard Chang)