Time from incident primary cancer until recurrence or second primary cancer: Risk factors and impact in general practice.
OBJECTIVE
Specialised follow-up care after cancer treatment is changing towards increased involvement of general practice. To ensure timely detection of new cancer events, knowledge is warranted on the timing of cancer recurrence (CR) and second primary cancer (SPC), including risk factors for CR.


METHODS
This population-based register study included 67,092 patients diagnosed with malignant melanoma, bladder, lung, ovarian, endometrial, colorectal and breast cancer in Denmark in 2008-2016. The time from primary cancer to CR or SPC and risk factors for prolonged time to CR were analysed and stratified on sex and primary cancer type.


RESULTS
Cancer recurrence proportions ranged from 6% to 35%. The risk of CR increased profoundly within the first 3 years and then levelled off, except for breast cancer. A total of 3%-6% of patients had SPC, with monotonously increasing cumulative incidence proportions. Besides primary tumour characteristics, lower educational level, living alone and comorbidity were associated with earlier CR. For example, in female malignant melanoma, HRs and 95% confidence intervals were 0.47 (0.37-0.61) for high educational level, 1.40 (1.16-1.68) for living alone and 2.38 (1.53-3.70) for high comorbidity.


CONCLUSION
The results may inform stratified risk assessment in decision of frequency, location and duration of post-cancer follow-up care.
['Rasmussen|Linda Aagaard|LA|https://orcid.org/0000-0002-9753-2008', 'Jensen|Henry|H|https://orcid.org/0000-0003-4040-7334', 'Virgilsen|Line Flytkjaer|LF|', 'Falborg|Alina Zalounina|AZ|', 'Møller|Henrik|H|', 'Vedsted|Peter|P|']
D000359:Aftercare D000368:Aged D001943:Breast Neoplasms D000073116:Cancer Survivors D015179:Colorectal Neoplasms D015897:Comorbidity D003718:Denmark D018572:Disease-Free Survival D004522:Educational Status D016889:Endometrial Neoplasms D005260:Female D058006:General Practice D006801:Humans D015994:Incidence D008175:Lung Neoplasms D008297:Male D008545:Melanoma D008875:Middle Aged D009364:Neoplasm Recurrence, Local D009369:Neoplasms D016609:Neoplasms, Second Primary D010051:Ovarian Neoplasms D016016:Proportional Hazards Models D012042:Registries D012111:Residence Characteristics D012737:Sex Factors D012878:Skin Neoplasms D013997:Time Factors D001749:Urinary Bladder Neoplasms
recurrence cancer survivors care transition primary health care second primary neoplasms