A system and method are provided for accessing and cannulating a target mass. The system includes a combined cystotome and access needle that provides for efficient operation. The access needle may be embodied as a polymeric sheath with a piercing stylet configured to extend beyond its distal end. The device embodiments allow a user to access and cannulate a target site such as, for example, a pancreatic pseudocyst with a single device. The device is also configured to allow introduction of a wire guide such that the cannulated target site can readily receive a wire-guided stent, or a stent delivered over the access needle.