Table 2.

Synopsis of studies for the impact of COVID-19 on skin cancer outcomes

Paper	Study Characteristics	Key Findings
Barruscotti et al, 20206	Retrospective review of all surgical excisions performed in the dermatologic surgery room at Fondazione IRCCS Policlinico San Matteo from February 22–May 3, 2020 (n = 163).	Melanoma diagnoses in the 2020 lockdown period was reduced 60% from previous years (prevalence, 3.7%; 95% CI, 1–8). 30% relative decrease in all dermatologic surgical activity.
Earnshaw et al, 20207	Retrospective review of a cancer tracking database in the UK from February to April 2020.	34.3% reduction in urgent skin cancer referrals during the study period. Largest decrease observed in April 2020 (56.4% lower cases than April 2019). Lower total skin cancers diagnosed in March 2020 compared with previous years.
Nolan et al, 20208	Prospective cohort of patients undergoing skin cancer surgery from 32 plastic surgery units in the United Kingdom from March 16–June 14, 2020 (n = 1549). Retrospective patient data on melanoma surgery (March 23–June 14, 2020) from 20 plastic surgery units (n = 501).	Treatment of KC decreased by 27%–47% throughout April and May 20. SCCs prioritized over BCCs, and at the pandemic’s peak SCCs comprised 71% of excisions. 77% of Mohs micrographic surgeons stopped procedures.
Filoni et al, 20219	Retrospective review of all dermatologic and surgical activity performed in an Italy-based melanoma skin unit from February 23–May 21, 2020.	When compared with the previous calendar year, surgical excisions during lockdown increased 31.7% and SLNBs decreased 29%. Dermatologic follow-up decreased 30.2%, whereas surgical follow-up decreased 37%.
Ferrara et al, 20214	Standards-based audit retrospective review comparing the number first diagnoses of tumors finalized during weeks 11–20 of 2020 at an Italian pathology unit (n = 2751).	All cancer diagnoses fell in 2020 by 44.9% compared with 2018 and 2019. Melanoma and KC represented 56.7% of all missing diagnoses.
Nicholson et al, 202048	Survey study for all BSDS members practicing Mohs over the course of 3 wk starting April 27, 2020 (n = 47).	49% of respondents stopped Mohs surgery. When Mohs was performed, 35% reported decrease use of grafts/flaps, 81% reported increased use of dissolvable sutures, and 29% reported increase prescribing of prophylactic antibiotics.
Schauer et al, 202047	Retrospective study of a UK hospital laboratory database January 27–March 22, 2020; and March 23–May 18, 2020 (inclusive) (n = 17).	Most cases represented early or thin melanomas (7% and 44% for prelockdown and during lockdown). Malignant melanoma detection rates were higher during lockdown (5.73%).
Ricci et al, 202019	Cross-sectional study of all consecutive primary malignant melanomas from the Pathology Registry of IDI-IRCCS (Rome, Italy) during the COVID-19 pandemic (n = 237).	Mean number of melanomas diagnosed per day: 0.6 during lockdown vs 2.3 prelockdown vs 1.3 postlockdown. Mean Breslow thickness was 0.88 (95% CI, 0.50–1.26) prelockdown and 1.96 (95% CI, 1.16–2.76) postlockdown. Proportion of ulceration was 5.9% (95% CI, 2.4%–11.7%) prelockdown and 23.5% (95% CI, 10.8%–41.2%) postlockdown.
Valenti 202146	Retrospective study of excised advanced melanoma and keratinocyte cancers in an Italian dermatosurgery division from May 18–November 18, 2020 (n = 265).	The number of advanced skin cancers was significantly higher during lockdown (54 vs 22; OR, 2.64; 95% CI, 1.56–4.47; P = .0003). The number of advanced SCCs (OR, 4.60; 95% CI, 1.31–16.18; P = .0175) and BCCs (OR, 2.15; 95% CI, 1.14–4.07; P = .0187) was significantly higher during lockdown.
Marson 202143	Retrospective study of 143 US dermatology practices (350 providers) covering 4.7 million patients across 13 geographically distributed states.	Average monthly number of skin cancers decreased during lockdown compared with before (cutaneous melanoma mean difference, −126.5; cSCC, −2086.6; BCC, −3305.8) and immediately after (cutaneous melanoma, −144.7; cSCC, −2057.7; BCC, −3370.0). Largest decreases were observed during April 2020 (cutaneous melanomas, −69.6%; SCCs, −77.7%; BCCs, −85.9%).
Andrew 202144	Retrospective review of data from the Northern Cancer Network from March 23–June 23, 2020 compared with the same period in 2019.	Skin cancer diagnoses decreased 68.61% (P<.01). Waiting times were decreased during COVID-19 compared with before (median 8 d and 12 d, respectively; P<.0001).

We found 11 studies that reported short-term skin cancer outcomes because of the pandemic, only one of which was based in the United States. At the time of this review, no studies were found reporting long-term patient outcomes because of surgical treatment delay.

Abbreviation: BCC, basal cell carcinoma; BSDS, British Society for Dermatological Surgery; KC, Keratinocyte cancer; SCC, squamous cell carcinoma.