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Updated: May 11, 2026

Competing-Risk Nomogram for Predicting Cancer-Specific Survival in Multiple Primary Colorectal Cancer Patients after Surgery
Published on: September 27, 2024
Multiple primary malignancies--a retrospective analysis at a single center in Turkey
Erkan Arpaci1, Saadet Tokluoglu, Tarkan Yetigyigit
1Department of Medical Oncology, Sakarya University, Sakarya Education and Research Hospital, Sakarya, Turkey. doktorerkan2001@yahoo.com
Background:
A literature review on 1,104,269 cancer patients concluded that the prevalence of multiple primary malignancies (MPM) is between 0.73% and 11.7%. MPMs seem to have higher incidence than that influenced by hazard only. The purpose of this study was to investigate clinically useful information for effective screening for synchronous and metachronous second primary cancers and to identify a potential surveillance protocol.
Materials And Methods:
Using statistical and epidemiological indicators we evaluated the patients with MPMs (double locations) admitted to Dr. Abdurrahman Yurtarslan Ankara Oncology Education and Research Hospital between 1981 and 2010.
Results:
Out of the 130 cases, 24 (18.4%) were synchronous while 106 cases (81.6%) were metachronous tumours. Mean interval time from first to second primary cancers was 4.65 years (0-27 years). The most frequent malignant associations were breast-breast, breast-endometrium and breast-ovary. Both primary and secondary tumors tended to be in an advanced stage explained by the low compliance of the patients to follow-up.
Conclusions:
The possibility that MPMs exist must always be considered during pretreatment evaluation. Screening procedures are especially useful for the early detection of associated tumors, whereas careful monitoring of patients treated for primary cancer and a good communication between patients and medical care teams should ensure early detection of secondary tumors, and subsequent appropriate management.