Diagnosis and Treatment of Basal Cell Carcinoma in Specialized Dermatology Units: A Clinical Practice Guideline

Follow-up of Patients With Keratinocyte Carcinoma: A Systematic Review of Clinical Practice Guidelines

Importance

Patients treated for cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), collectively called keratinocyte carcinoma (KC), are at risk for recurrence, metastasis, and additional primary cutaneous malignant neoplasms. It is unclear how often patients should be seen for follow-up skin examination after initial treatment of KC.

Objective

To summarize the recommendations and evaluate the methodological quality of clinical practice guidelines for dermatologic follow-up of patients with BCC and invasive SCC.

Evidence Review

PubMed, MEDLINE, and Embase were searched for relevant articles published from January 2010 to March 2022. Search terms included guideline, squamous cell carcinoma, and basal cell carcinoma. National or international guidelines containing recommendations for follow-up frequency after a diagnosis of localized cutaneous KC were included. Quality was assessed using the 6 domains of the Appraisal of Guidelines Research and Evaluation II (AGREE II) tool: (1) scope and purpose; (2) stakeholder development; (3) rigor of development; (4) clarity of presentation; (5) applicability; and (6) editorial independence. The Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) was used to guide study reporting.

Findings

Among the 14 guidelines meeting eligibility criteria, there was little consensus on the appropriate follow-up frequency after initial KC treatment. Overall duration of follow-up ranged from a single posttreatment visit to lifelong surveillance. Most guidelines stratified their recommendations by recurrence risk. For low-risk BCC and guidelines that did not stratify by risk, follow-up recommendations ranged from every 6 to 12 months. For high-risk BCC, 1 guideline suggested follow-up every 3 months, while 4 recommended every 6 months. For low-risk SCC, 5 guidelines recommended annual follow-up; 3 guidelines, every 6 months; and 1 guideline, every 3 months. For high-risk SCC, recommendations included a range of follow-up frequencies, spanning every 3 months (n = 5 guidelines), 4 months (n = 1), 6 months (n = 6), or annually (n = 4). One guideline did not use risk stratification and recommended annual screening. The highest scoring AGREE II domain was "scope and purpose," which assessed the guideline's overall objectives, and the lowest scoring was "applicability," which assessed barriers and facilitators to implementation.

Conclusions and Relevance

The findings of this systemic review highlight variations in follow-up recommendations for patients after initial treatment for KC. Randomized clinical trials are needed to define an optimal follow-up regimen.

Clinical Application of Pharmacogenetic Markers in the Treatment of Dermatologic Pathologies

Dermatologic pathologies are the fourth most common cause of non-fatal disease worldwide; however, they produce a psychosocial, economic, and occupational impact equal to or greater than other chronic conditions. The most prevalent are actinic keratosis, followed by basal-cell carcinoma, in a lesser proportion acne vulgaris, psoriasis, and hidradenitis suppurativa, among others, and more rarely dermatitis herpetiformis. To treat actinic keratosis and basal-cell carcinoma, 5-fluorouracil (5-FU) 0.5% is administered topically with good results, although in certain patients it produces severe toxicity. On the other hand, dapsone is a drug commonly used in inflammatory skin conditions such as dermatitis herpetiformis; however, it occasionally causes hemolytic anemia. Additionally, biologic drugs indicated for the treatment of moderate-to-severe psoriasis and hidradenitis suppurativa have proved to be effective and safe; nevertheless, a small percentage of patients do not respond to treatment with biologics in the long term or they are ineffective. This interindividual variability in response may be due to alterations in genes that encode proteins involved in the pathologic environment of the disease or the mechanism of action of the medication. Pharmacogenetics studies the relationship between genetic variations and drug response, which is useful for the early identification of non-responsive patients and those with a higher risk of developing toxicity upon treatment. This review describes the pharmacogenetic recommendations with the strongest evidence at present for the treatments used in dermatology, highlighting those included in clinical practice guides. Currently, we could only find pharmacogenetic clinical guidelines for 5-FU. However, the summary of product characteristics for dapsone contains a pharmacogenetic recommendation from the United States Food and Drug Administration. Finally, there is an enormous amount of information from pharmacogenetic studies in patients with dermatologic pathologies (mainly psoriasis) treated with biologic therapies, but they need to be validated in order to be included in clinical practice guides.