Chemosurgical Reports: Malignancies on the External Ear: Methods of Ablation and Reconstruction of Defects*

Embryologic Fusion Planes and the Spread of Cutaneous Carcinoma: A Review and Reassessment

“…These authors concluded that the spread of epithelial carcinomas was “markedly influenced by embryologic fusion planes.” 17 Levine and Bailin concluded that deep midf acial extension of tumor was probably due to embryologic lines of fusion 18 . Similar conclusions have been made about tumor arising on the auricle 19,20 . Subsequent authors have cited these articles in support of the view that tumors invade deeply along fusion planes with less of a tendency to cross them 21–33 …”

“…However, certain sites that they identified as sites of fusion clearly are not. Others similarly fail to make the distinction between sites of fusion and regions of merging 17,19,20,26 . As reviewed above, the two concepts represent two very different developmental processes.…”

Neoplasms of the Conchal Bowl: Treatment with Mohs Micrographic Surgery

“…Analysis of Figure 3 suggests that series of conchal bowl malignancies from otolaryngologists or tertiary referral cancer centers have a high ratio of SCC to BCC and a high incidence of distant metastasis 8,10,12,13,16,19,20 . The series reported from dermatologic surgeons have higher numbers of BCC to SCC and a negligible rate of metastasis 3,21,22 . This may reflect a referral pattern that sends more aggressive tumors directly to otolaryngologists for treatment.…”

Chemosurgical Report: Basal Cell Carcinoma Involving the External Auditory Canal—Treatment with Mohs Micrographic Surgery

“…Spread to the ear canal may occur from tumors that begin on the helix, antihelix, concha, tragus, and pre‐auricular area. Tumors arising in the pre‐and postauricular areas do not spread to the ear canal until very late in their history 15,16 …”

“…The spread of auricular cancers is believed to be due to the embryonic fusion planes which develop around the first branchial groove from six hillocks: three from the first branchial arch and three from the second branchial arch 15,16 . The tragus and superior helix form from the first branchial arch.…”