This is from AAPC online, above answers holds true for initial excision but not for re-excision.
Answer: Regardless of whether a skin excision is the initial procedure or a repeat excision, you should code a malignant lesion according to the size and margin noted in the medical record.
If the dimensions fit, you should use 11600 (Excision, malignant lesion including margins, trunk, arms, or legs; excised diameter 0.5 cm or less) again, because you state that the re-excision is because the margins were not clear and not because of some issue related to the scar or repair.
Add modifier: Because 11600 has a 10-day global period and the re-excision takes place within a week, you’ll need to append modifier 58 (Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period) to the second procedure. You should append modifier 58 when a procedure or service is planned or anticipated at the time of the original procedure (staged), is more extensive than the original procedure (which is the case in this scenario), or represents therapy following a surgical procedure.
Tip: You need not return the patient to the operating room to report modifier 58. Also, be sure to use the same malignant diagnosis again even if the most recent excision shows no cancer cells in the specimen, which is common in these re-excision situations.