Vermilion-lip tumors may be riskier than those on cutaneous lip
By David Douglas
NEW YORK (Reuters Health) - Compared with tumors on the cutaneous lip, cutaneous squamous cell carcinomas (cSCC) on the vermilion lip appears to carry a greater risk of metastasis, researchers have found.
Moreover, David M. Wang told Reuters Health by email "Our research showed that squamous cell carcinomas, one of the most common types of skin cancer, are more likely to spread to lymph nodes when they occur on the vermilion lip (pink part of lip) compared to the cutaneous lip (adjacent skin part of lip). We hypothesize that this may be due to the absence of a fat layer in the vermilion lip, which a tumor on the cutaneous lip would need to grow through to spread to lymph nodes."
In a paper online May 2 in JAMA Dermatology, Wang, of Case Western Reserve University School of Medicine in Cleveland, Ohio, and colleagues note that although the lip is considered a high-risk location, it is not clear whether this is true of the cutaneous lip, the vermilion lip, or both.
To investigate, the team retrospectively examined data from 303 patients with 310 primary cSCCs of the lip; 172 were vermilion and 138 were cutaneous. The median age at diagnosis was 68 years.
Local recurrence was seen in 6.4% of vermilion locations compared to 2.9% of cutaneous locations. Nodal metastasis occurred in 7.6% and 1.5%, respectively, and disease-specific death in 3.5% and 2.9%; for all-cause death, the rates were 26.7% and 29.0%.
The difference was statistically significant for nodal metastasis on the vermilion lip (P=0.01). On multivariable analysis, the risk of nodal metastasis was increased five-fold for vermilion-lip tumors.
The researchers note that cSCCs of the cutaneous lip "have a nodal metastasis risk similar to cSCCs in general (1.5%). Thus, vermilion involvement appears responsible for the increased risk associated with cSCC of lip."
Wang concluded, "Given the 5-fold difference in risk we identified between these two lip zones squamous cell carcinomas on the vermilion lip may benefit from earlier radiologic imaging for staging and treatment purposes. In addition, it may be warranted for future staging systems to take into account the increased risk associated with the vermilion-lip location."
Dr. Maie A. St. John, professor and chair of the department of head and neck surgery at the University of California, Los Angeles, stressed the importance of the heightened risk of nodal metastasis for cSCCs on the vermilion lip.
Dr. St. John, who was not involved in the study, added, "Vermilion involvement may merit radiologic nodal staging and inclusion in future tumor staging, since it was independently associated with higher-risk cSCC of the lip region."
JAMA Dermatol 2018.(c) Copyright Thomson Reuters 2018. Click For Restrictions - https://agency.reuters.com/en/copyright.html