Coding Corner

A dental cyst is submitted and a gross and microscopic exam is performed.  Would CPT code 88304 be the correct code to report for this cyst?
 
Per CPT, code 88304 is reported for a skin cyst, tag or debridement.  Examples would be simple skin cysts, skin polyp, skin tags, etc.  A dental cyst which develops on or within the gum line is a listed specimen per CPT and reported with code 88305.  There are many types of cysts in different locations and not all are classified to code 88304. Some can be 88305 and certain types of ovarian cysts such as dermoid cysts or cystadenomas are 88307.      
 
We have a surgical case and the specimen is a lung mass, where a definitive diagnosis cannot be provided.  Should we assign ICD-9 code 235.7 for “uncertain” behavior?
 
Per ICD-9, the definition of “uncertain” behavior is described as “tumors histomorphologically well-defined neoplasms, the subsequent behavior of which cannot be predicted from the present appearance.”  Uncertain behavior codes are assigned when a specimen is identified as a neoplasm that has characteristics showing it might become malignant and a distinction between benign and malignant cannot be determined as the cells may be in transformation to malignant.  So, it is the cells that are “uncertain” not because a definite diagnosis cannot be provided.  In this case assigning 786.6 (Swelling, mass, or lump in chest) would be most appropriate.