ICD-10-CM > N00-N99 > N80-N98 > N80 > N80.5 > N80.54 N80.54 Endometriosis of the appendix Non-Billable/Non-Specific Codes N80.541Superficial endometriosis of the appendixN80.542Deep endometriosis of the appendixN80.549Endometriosis of the appendix, unspecified depth