Table II.

Overview of literature on life expectancy

Study	Type	Participants/age	n	Treatment	Outcome	Limitations
Linos et al. (7) 2013	Prospective cohort study	Patients with KC, median age 69.0 years (IQR, 55.0-78.0 years)	1,360 patients with 1,739 KC	No treatment, destruction 2 types of surgery; - Elliptical excision - MMS	- Most patients were treated surgically - Choice of surgery was not influenced by the patients’ life expectancy - Higher incidences of complications were observed in the group of patients with LLE	- Observational design patient preference was not measured - A significant part of patients with an estimated LLE lived longer than 5 years
Linos et al. (8) 2016	Cross-sectional study	Patients with KC, aged ≥65 years, mean age 79 years	2,702 patients, 9653 KC	MMS, simple excision or electrodessication and curettage	- Most tumours were treated surgically - Type of treatment was not different between patients with normal life expectancy and LLE	- KC treated with topical therapies, radiotherapy and untreated KC were not included - Information about patient preferences was not available
Charles et al. (10) 2002	Retrospective study	Nonagenarians (90-99 years) with KC	99 patients	MMS	- Patients no comorbidities had a longer survival than patients with multiple comorbidities (measured with CCI). - Women survived longer than men. - No patient died within 30 days after surgery.	The variability in survival among patients within a particular CCI was broad. Therefore, predictions of life expectancy for individual patients are not very reliable.
Delaney et al. (11) 2013	Retrospective study	Patients with KC aged ≥90 years, mean age 92.3 years	214 patients	MMS	- No significant difference in survival in patients with different CCI scores. - Defect size, tumour characteristics, number of surgical stages and closure type did not affect survival rates.	Data about follow-up and causes of death were not available.
Pascual et al. (12) 2013	Prospective study	Patients with KC aged ≥80 years	130 patients	Surgery	Age, comorbidity (measured by the CCI), closure with a graft and the Barthel Index* before surgery were associated with increased mortality	An univariate analysis was performed, no multivariate analyses were performed
Rogers et al. (13) 2018	Retrospective study	Patients with KC aged ≥85 years, mean age 88.1 years	488 patients	MMS vs no MMS	- ACE-27 and ACCI scores can predict LLE - Higher comorbidity scores were associated with decreased survival	Retrospective study design

KC: keratinocyte carcinoma; IQR: interquartile range; MMS: Mohs micrographic surgery; LLE: limited life expectancy; CCI: Charlson Comorbidity Index; ACCI: age-adjusted Charlson comorbidity index.

^*An instrument measuring disability in terms of a person’s level of functional independence in personal activities of daily living.