Second primary malignancies in colorectal cancer patients

Prognosis and clinicopathological features of patients with early-onset and late-onset colorectal cancer with second primary malignancies

BACKGROUND AND AIM

The risk of developing a second primary malignancy differs among colorectal cancer patients in different age groups. This study aimed to investigate the differences in prognosis and clinicopathological features of patients with early-onset colorectal cancer and late-onset colorectal cancer who developed second primary malignancies.

METHODS

The study included 15 489 patients who underwent surgery for colorectal cancer at Fudan University Shanghai Cancer Center between January 2008 and December 2018. Data pertaining to these patients were derived from the database.

RESULTS

A total of 680 (4.5%) patients subsequently developed a second primary malignancy. Considering death as a competing event, the 10-year cumulative risk of second primary malignancy for early-onset colorectal cancer was 5.3%, compared with 7.3% for late-onset colorectal cancer. Cox analysis showed that late-onset colorectal cancer, colon cancer, smaller tumor size, and fewer tumor nodules without residual lymph node structure, chemotherapy, and radiotherapy were independent risk factors for second primary malignancy. In our patient cohort, early-onset colorectal cancer was associated with better prognosis compared to late-onset colorectal cancer, for both overall survival and second primary malignancy-free survival. In addition, there was insufficient evidence that early-onset colorectal cancer also affected prognosis after the occurrence of second primary malignancies.

CONCLUSIONS

The risk of early-onset colorectal cancer subsequently developing second primary malignancy was significantly lower than late-onset colorectal cancer, and the second primary malignancies of early-onset colorectal cancer were more likely to be colorectal cancer. Overall survival and second primary malignancy-free survival of early-onset colorectal cancer were consistently better than late-onset colorectal cancer.

Germline DNA Damage Repair Gene Alterations in Patients with Metachronous Breast and Colorectal Cancer

A hereditary component of breast (BC) and colorectal cancer (CRC) has been described in approximately one-third of these tumor types. BC patients have an increased risk of developing CRC as a second primary tumor and vice versa. Germline genomic variants (NextSeq550, Illumina) were investigated in 24 unrelated BC and/or CRC patients and 7 relatives from 3 index patients. Fifty-six pathogenic or likely pathogenic variants were identified in 19 of 24 patients. We detected single-nucleotide variants (SNVs) in CRC predisposition genes (MLH1 and MUTYH) and other promising candidates (CDK5RAP3, MAD1L1, NOS3, and POLM). Eighteen patients presented SNVs or copy number variants (CNVs) in DNA damage repair genes. We also identified SNVs recently associated with BC or CRC predisposition (PABPC1, TYRO3, MAP3K1, SLC15A4, and LAMA1). The PABPC1c.1255C>T variant was detected in nine unrelated patients. Each patient presented at least one SNV/CNV in a candidate gene, and most had alterations in more than one gene, reinforcing a polygenic model for BC/CRC predisposition. A significant fraction of BC/CRC patients with a family history of these tumors harbored deleterious germline variants in DNA repair genes. Our findings can lead to strategies to improve the diagnosis, genetic counseling, and treatment of patients and their relatives.

Synchronous Primary Gallbladder and Colon Adenocarcinoma: A Case Report and Systematic Literature Review

Synchronous primary malignancies, defined as two or more primary malignancies diagnosed simultaneously or within six months, are uncommon and present unique diagnostic and therapeutic challenges. Synchronous primary adenocarcinoma of the gallbladder and colon is particularly rare. We report a case of a 48-year-old female presenting with persistent right upper abdominal pain. Laboratory tests and imaging studies initially suggested xanthogranulomatous cholecystitis. However, subsequent laparoscopic cholecystectomy and pathological examination revealed a moderately differentiated adenocarcinoma of the gallbladder (pT2bN1M0). Further staging with CT and PET-CT scans identified a suspicious mass in the transverse colon, confirmed by colonoscopy and surgical resection as well-differentiated adenocarcinoma of the transverse colon (pT3N0M0). Immunohistochemistry and genetic profiling of both tumors indicated distinct primary origins without loss of mismatch repair (MMR) protein expression. The patient underwent additional liver resection, lymph node dissection, and right extended hemicolectomy. She is currently undergoing further staging and awaiting chemotherapy. A review of English-language literature revealed eight reported cases of synchronous primary gallbladder and colorectal cancer and a total of 13 with synchronous primary malignancy of other organs. Such cases are rare and diagnostically complex cases. Common factors contributing to multiple primary malignancies (MPM) include genetic predispositions, previous cancer treatments, and lifestyle factors such as smoking and alcohol consumption. This case underscores the importance of thorough investigation and prompt treatment in patients suspected of having MPM. Advances in diagnostic imaging and molecular profiling are crucial for early detection and tailored therapeutic strategies. Standardized guidelines for managing synchronous cancers are needed to improve patient outcomes.

A nomogram for overall survival of second primary cancers following upper-tract urothelial carcinoma: a SEER population-based study

Background

With improving prognosis in upper-tract urothelial carcinoma (UTUC), an increasing number of second primary malignancies (SPMs) are being identified. However, there is limited research on SPMs following UTUC. This study aims to evaluate the risk of SPMs in UTUC patients and create a nomogram to predict their survival rates.

Methods

Utilizing data from the Surveillance, Epidemiology, and End Results (SEER) database, we assessed the risk of SPMs among UTUC patients. Additionally, we developed and validated an overall survival (OS) nomogram for SPM patients post-UTUC diagnosis.

Results

The prevalence of SPMs among UTUC patients was 30.23%, with solid tumors being the most prevalent type of second malignancy, constituting 95.30% of all SPMs. The overall risk of SPMs was significantly elevated across all subgroups. Univariate and multivariate Cox regression analyses identified age, race, gender, UTUC SEER historic stage, surgery, SPM site, histologic type, grade, and SEER historic stage as independent prognostic factors for SPM OS. Subsequently, we developed a nomogram for predicting SPM OS. The C-index for the training and validation sets were 0.72 [95% confidence interval (CI): 0.70-0.74] and 0.71 (95% CI: 0.67-0.75), respectively. The area under the curve (AUC) demonstrated good performance of our model in predicting the 3-year (0.73 and 0.737) and 5-year (0.723 and 0.733) OS of SPMs in both sets.

Conclusions

This study represents the first comprehensive analysis of SPM incidence in UTUC patients and introduces a nomogram for predicting SPM prognosis.

Incidence of late recurrence and second primary cancers 5-10 years after non-metastatic colorectal cancer

The fraction of patients who are cancer-free survivors 5 years after curative-intended surgery for colorectal cancer (CRC) is increasing, suggesting that extending surveillance beyond 5 years may be indicated. Here we estimate the incidence of late recurrence, metachronous CRC, and second primary cancers 5-10 years postoperative. All patients resected for UICC stage I-III CRC in Denmark through 2004-2013 were identified. Through individual-level linkage of nationwide health registry data, recurrence status was determined using a validated algorithm. Cancer-free survivors 5 years after surgery, were included. Cumulative incidence functions (CIF) of late recurrence, metachronous CRC, and second primary cancer 5-10 years postoperative were constructed. Subdistribution hazards ratios (sHR) were computed using Fine-Gray regression. Among 8883 patients, 370 developed late recurrence (5-10-year CIF = 4.1%, 95%CI: 3.7%-4.6%), 270 metachronous CRC (5-10-year CIF = 3.0%, 95%CI: 2.7%-3.4%), and 635 a second primary cancer (5-10-year CIF = 7.2%, 95%CI: 6.7%-7.7%). The risk of late recurrence was reduced for patients operated in 2009-2013 compared to 2004-2008 (2.9% vs. 5.6%, sHR = 0.52, 95% CI: 0.42-0.65). The risk of metachronous CRC was likewise reduced from 4.1% to 2.1% (sHR = 0.50, 95%CI: 0.39-0.65). While the risk of second primary cancer did not change between 2009-2013 and 2004-2008 (7.1% vs. 7.1%, sHR = 0.98, 95% CI: 0.84-1.15). Using nation-wide 10-year follow-up data, we document that the incidences of late recurrence and metachronous CRC are low and decreasing from 2004 to 2013. Thus, despite increasing numbers of long-term cancer survivors, the data do not advocate for extending CRC-specific surveillance beyond 5 years.

Double versus Single Primary Malignant Neoplasm of Breast and Colorectal Cancer: A Case-Control Study

PURPOSE

Breast cancer (BC) and colorectal cancer (CRC) are common in female. This study compared survival time between women affected with both cancers with ones with single BC or single CRC.

METHOD

Medical records of subjects with both BC & CRC (June 1, 2010, to June 30, 2021) were reviewed. Age-matched subjects who had BC or CRC alone were used as control. Survival analysis using Kaplan-Meier method was performed.

RESULT

There were 63 double cancers [40 BC first (DBC): 23 CRC first (DCRC), mean age±SD 60.5±9.9 and 60.9±12.2 years] and 76 subjects in single cancer group [53 SBC: 23 SCRC, mean age 57.4±11.3 and 61.1±12.5 years]. The 5-year survival rate of the double cancer group was 74.6% and the single cancer group was 63.2%. D-group had slightly longer survival time than S-group (116.5±4.0 vs. 101.3±5.5, p=0.055). In D-group, the occurrence of addition of other primary cancers were more common (p=0.015). The second cancer occurred 61.7±45.3 months later in DBC group, and 39.1±26.6 months later in DCRC group (p=0.016). SCRC had shorter survival time vs. DCRC group (p=0.031). SBC and DBC had no different in mean survival time.

CONCLUSION

BC and CRC could occur as a part of multiple primary cancers. Detection of more than one cancer did not lead to decrease survival if the second cancer was early detected and treated. The occurrence of the second cancer might be beyond 5 years after the diagnosis of the first cancer. Thus, longer surveillance may be warranted. Awareness and provision of early screening should be offered to individuals diagnosed with either primary cancer. Detection of more than one cancer did not lead to shorter survival.

Mortality patterns of patients with tonsillar squamous cell carcinoma: a population-based study

Objective

Tonsillar squamous cell carcinoma (TSCC) and second primary malignancies (SPMs) are the most common causes of mortality in patients with primary TSCC. However, the competing data on TSCC-specific death (TSD) or SPM-related death in patients with TSCC have not been evaluated. This study aimed to analyze the mortality patterns and formulate prediction models of mortality risk caused by TSCC and SPMs.

Methods

Data on patients with a first diagnosis of TSCC were extracted as the training cohort from the 18 registries comprising the Surveillance, Epidemiology, and End Results (SEER) database. A competing risk approach of cumulation incidence function was used to estimate cumulative incidence curves. Fine and gray proportional sub-distributed hazard model analyses were performed to investigate the risk factors of TSD and SPMs. A nomogram was developed to predict the 5- and 10-year risk probabilities of death caused by TSCC and SPMs. Moreover, data from the 22 registries of the SEER database were also extracted to validate the nomograms.

Results

In the training cohort, we identified 14,530 patients with primary TSCC, with TSCC (46.84%) as the leading cause of death, followed by SPMs (26.86%) among all causes of death. In the proportion of SPMs, the lungs and bronchus (22.64%) were the most common sites for SPM-related deaths, followed by the larynx (9.99%), esophagus (8.46%), and Non-Melanoma skin (6.82%). Multivariate competing risk model showed that age, ethnicity, marital status, primary site, summary stage, radiotherapy, and surgery were independently associated with mortality caused by TSCC and SPMs. Such risk factors were selected to formulate prognostic nomograms. The nomograms showed preferable discrimination and calibration in both the training and validation cohorts.

Conclusion

Patients with primary TSCC have a high mortality risk of SPMs, and the competing risk nomogram has an ideal performance for predicting TSD and SPMs-related mortality. Routine follow-up care for TSCC survivors should be expanded to monitor SPMs.

A prognostic nomogram and risk classification system of elderly patients with extraosseous plasmacytoma: a SEER database analysis

BACKGROUND

The survival trends and prognostic factors of patients with extraosseous plasmacytoma (EOP) or extramedullary plasmacytoma (EMP) have not been reported in recent years. The objective of this study was to develop a novel nomogram and risk stratification system for predicting the overall survival (OS) of elderly patients with EOP based on the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

The demographic characteristics of 900 patients aged 60 years and above, diagnosed with EOP between 2000 and 2019, were extracted from the SEER database. The patient population was randomly divided into a training cohort and an internal validation cohort in a ratio of 7:3. Univariate and multivariate Cox regression analyses were conducted to identify independent predictors of prognosis in elderly EOP patients, followed by developing a nomogram for prognostic assessment. The performance of the model was evaluated through receiver-operating characteristic (ROC) curves, C-index, calibration curves for calibration accuracy assessment, and decision curve analysis (DCA) to assess its clinical utility. All elderly EOP patients were stratified into three risk subgroups by cutoff value utilizing X-tile software based on their total OS scores for comparative analysis purposes. Kaplan-Meier (K-M) survival curve analysis was employed to validate any observed differences in OS among these three risk groups.

RESULTS

Six factors including age, year of diagnosis, marital status, primary site, surgery, and prior tumor history were identified to be independently predictive of the OS of elderly patients with EOP, and these predictors were included in the construction of the nomogram. The 1-, 3-, and 5-year area under the curves (AUCs) for OS were 0.717, 0.754, and 0.734 in the training cohort and 0.740, 0.730, and 0.765 in the validation cohort, respectively. The C-index values in the two cohorts were 0.695 and 0.690. The calibration curves and DCA exhibit commendable consistency and validity, respectively, thereby demonstrating their robust performance. The training set was stratified into low-, medium-, and high-risk subgroups based on the optimal cutoff points (167.8 and 264.8) identified. The K-M curve and cumulative risk curve exhibited statistically significant disparities in survival rates among the groups.

CONCLUSIONS

We developed a nomogram and risk classification system, which can serve as an intuitive and effective tool for clinicians to enhance the prediction of OS in elderly EOP patients, thereby facilitating the formulation of more rational and personalized treatment strategies.

Investigating the tissue specificity and prognostic impact of cis-regulatory cancer risk variants

The tissue-specific incidence of cancers and their genetic basis are poorly understood. Although prior studies have shown global correlation across tissues for cancer risk single-nucleotide polymorphisms (SNPs) identified through genome-wide association studies (GWAS), any shared functional regulation of gene expression on a per SNP basis has not been well characterized. We set to quantify cis-mediated gene regulation and tissue sharing for SNPs associated with eight common cancers. We identify significant tissue sharing for individual SNPs and global enrichment for breast, colorectal, and Hodgkin lymphoma cancer risk SNPs in multiple tissues. In addition, we observe increasing tissue sharing for cancer risk SNPs overlapping with super-enhancers for breast cancer and Hodgkin lymphoma providing further evidence of tissue specificity. Finally, for genes under cis-regulation by breast cancer SNPs, we identify a phenotype characterized by low expression of tumor suppressors and negative regulators of the WNT pathway associated with worse freedom from progression and overall survival in patients who eventually develop breast cancer. Our results introduce a paradigm for functionally annotating individual cancer risk SNPs and will inform the design of future translational studies aimed to personalize assessment of inherited cancer risk across tissues.

Co-Occurrence of Germline Genomic Variants and Copy Number Variations in Hereditary Breast and Colorectal Cancer Patients

Hereditary Breast and Ovarian Cancer (HBOC) syndrome is an autosomal dominant disease associated with a high risk of developing breast, ovarian, and other malignancies. Lynch syndrome is caused by mutations in mismatch repair genes predisposing to colorectal and endometrial cancers, among others. A rare phenotype overlapping hereditary colorectal and breast cancer syndromes is poorly characterized. Three breast and colorectal cancer unrelated patients fulfilling clinical criteria for HBOC were tested by whole exome sequencing. A family history of colorectal cancer was reported in two patients (cases 2 and 3). Several variants and copy number variations were identified, which potentially contribute to the cancer risk or prognosis. All patients presented copy number imbalances encompassing PMS2 (two deletions and one duplication), a known gene involved in the DNA mismatch repair pathway. Two patients showed gains covering the POLE2 (cases 1 and 3), which is associated with DNA replication. Germline potentially damaging variants were found in PTCH1 (patient 3), MAT1A, and WRN (patient 2). Overall, concurrent genomic alterations were described that may increase the risk of cancer appearance in HBOC patients with breast and colorectal cancers.

Incidence and risk outcomes of second primary malignancy of patients with post-operative colorectal cancer

BACKGROUND AND AIMS

This study aimed to investigate the incidence and the risk factors of incidence for second primary malignancies (SPMs) onset among survivors diagnosed with colorectal cancer (CRC).

METHODS

A large population-based cohort study was performed. Data of patients diagnosed with CRC was identified and extracted from 8 cancer registries of Surveillance, Epidemiology, and End Results database from January 1990 to December 2017. The outcome of interest was percentage and common sites of SPM onset after primary CRC diagnosis. The cumulative incidence and standardize incidence rates (SIRs) were also reported. Afterwards, we estimated sub-distribution hazards ratios (SHRs) and relative risks (RRs) for SPM occurrence using multivariable competing-risk and Poisson regression models, respectively.

RESULTS

A total of 152,402 patients with CRC were included to analyze. Overall, 23,816 patients of all CRC survivors (15.6%) were reported SPM occurrence. The highest proportion of SPMs development after primary CRC diagnosis was second CRC, followed by lung and bronchus cancer among all survivors. Also, CRC survivors were more susceptible to develop second gastrointestinal cancers (GICs). Besides, pelvic cancers were analyzed with a relative high proportion among patients who received RT in comparison to those without RT. The cumulative incidence of all SPMs onset was 22.16% (95% CI: 21.82-22.49%) after near 30-year follow-up. Several factors including older age, male, married status, and localized stage of CRC were related to the high risk of SPMs onset. In treatment-specific analyses, RT was related to a higher cumulative incidence of SPMs occurrence (all SPMs: 14.08% vs. 8.72%; GICs: 2.67% vs. 2.04%; CRC: 1.01% vs. 1.57%; all p < 0.01). Furthermore, the increased risk of SPMs onset was found among patients who received RT than patients within the NRT group (SHR: 1.50, 95% CI: 1.32-1.71), p < 0.01; RR: 1.61, 95% CI: 1.45-1.79, p < 0.01).

CONCLUSION

The present study described the incidence pattern of SPM among CRC survivors and identified the risk factors of the SPM onset. RT treatment for patients diagnosed with CRC may increase the risk of SPMs occurrence. The findings suggest the need for long-term follow-up surveillance for these patients.

Better survival and prognosis in SCLC survivors after combined second primary malignancies: A SEER database-based study

With recent advances in treatment modalities, the survival time for patients with small cell lung cancer (SCLC) has increased, along with the likelihood of recurrence of a second primary tumor. However, patient treatment options and prognosis remain uncertain. This research evaluated the survival rates of patients with SCLC with a second malignancy, aiming to provide new insights and statistics on whether to proceed with more active therapy. SCLC patients were selected based on the Surveillance, Epidemiology, and End Results (SEER) database, updated on April 15, 2021. We defined those with SCLC followed by other cancers (1st of 2 or more primaries) in the sequence number as S-second primary malignant cancer (S-SPM). Those who had other cancers followed by SCLC (2nd of 2 or more primaries) were defined as OC-SCLC. We performed Kaplan-Meier survival analysis, life table analysis, univariate analysis, stratified analysis, and multiple regression analysis of patient data. We considered the difference statistically meaningful at P < .05. After selection, data for 88,448 participants from the SEER database was included in our analysis. The mean survival time for patients with S-SPM was 69.349 months (95% confidence interval [CI]: 65.939, 72.759), and the medium duration of survival was 34 months (95% CI: 29.900, 38.100). Univariate analysis showed that for overall survival, the hazard ratio (HR) of S-SPM was 0.367 (95% CI: 0.351, 0.383), which was 0.633 lower than that of patients with solitary SCLC and 0.606 lower than that of patients with OC-SCLC. For cancer-specific survival (CSS), the HR of S-SPM was 0.285 (95% CI: 0.271, 0.301), which was 0.715 lower than for patients with solitary SCLC and 0.608 lower than that for patients with OC-SCLC. Multiple regression analysis showed that the HR values of S-SPM were lower than those of patients with single SCLC and those with OC-SCLC, before and after adjustment for variables. Kaplan-Meier survival curves showed that patients with S-SPM had significantly better survival times than the other groups. The survival time and prognosis of patients with S-SPM were clearly superior to those with single SCLC and OC-SCLC.

Genetic mutation and tumor microbiota determine heterogenicity of tumor immune signature: Evidence from gastric and colorectal synchronous cancers

Both colorectal and gastric cancer are lethal solid-tumor malignancies, leading to the majority of cancer-associated deaths worldwide. Although colorectal cancer (CRC) and gastric cancer (GC) share many similarities, the prognosis and drug response of CRC and GC are different. However, determinants for such differences have not been elucidated. To avoid genetic background variance, we performed multi-omics analysis, including single-cell RNA sequencing, whole-exome sequencing, and microbiome sequencing, to dissect the tumor immune signature of synchronous primary tumors of GC and CRC. We found that cellular components of juxta-tumoral sites were quite similar, while tumoral cellular components were specific to the tumoral sites. In addition, the mutational landscape and microbiome contributed to the distinct TME cellular components. Overall, we found that different prognoses and drug responses of GC and CRC were mainly due to the distinct TME determined by mutational landscape and microbiome components.

Second Primary Cancers following Colorectal Cancer in Sicily, Italy

Simple Summary

This study addressed the under-investigated issue of second primary cancer occurring in colorectal cancer survivors. Our aim was to explore whether patients recovered from a first colorectal cancer were at higher risk of developing a subsequent primary cancer. The hypothesis was that exposure to cancer treatment, enhanced health surveillance and shared risk factors may lead to an excess risk of second primary cancer in this population. The number of cases of second primary cancer exceeded the expected in this population, mainly driven by female genital cancers, and especially observed in the first years after colorectal cancer diagnosis. Our findings are overall consistent with previous studies, providing valuable information to better characterize and predict mortality from second primary cancer in subjects who suffered from first colorectal cancer.

Abstract

Background: Cancer survivors are at risk of developing second primary cancers (SPC). We investigated the risk of SPC in colorectal cancer (CRC) survivors in Sicily, Southern Italy. Methods: We analyzed data from the Eastern Sicily cancer registry covering 2.5 million people diagnosed and followed up between 2003 and 2017. We calculated the standardized incidence ratio (SIR) and 95% confidence interval (CI) of SPC overall and by cancer type, using the general Sicily population rates as reference. Results: A total of 19,040 cases of CRC and 1453 cases of SPC were included in the analysis. Mean age of occurrence of SPC was 68.1. The SIR for any SPC was 1.11 (95% CI 1.05–1.17); it was higher in women (1.18; 95% CI 1.08–1.29) than in men (1.07; 95% CI 0.97–1.14, p-value of difference 0.07). The SIR was increased for SPC from the ovary (SIR 2.01; 95% CI 1.33–2.95), kidney (SIR 2.00; 95% CI 1.54–2.56), endometrium (SIR 1.94; 95% CI 1.45–2.54), bladder (SIR 1.22, 95% CI 1.04–1.43) and stomach (1.29; 95% CI 0.98–1.66). The SIR for CRC as SPC was 0.84 (95% CI 0.70–1.01). No increased incidence was found for lung, prostate, breast, thyroid and liver cancer. The SIR for SPC overall and several cancers decreased with time of follow-up. Conclusions: In this population, CRC survivors have an 11% higher risk of developing a SPC than the general population, particularly cancers of the ovary, kidney, endometrium, bladder and stomach. Follow-up for SPC is required, especially during the first 5 years from CRC diagnosis.

Mediastinal thymoma in a patient with previous rectal and breast cancers: A report of a case with multiple primary cancers and review of literature

A 42-year-old female patient with intellectual disability was presented to us as a newly diagnosed case of thymoma. She was identified as a case of multiple primary cancers, including adenocarcinoma of the rectum, carcinoma of the breast, and mediastinal thymoma, in a 15-year period, who underwent chemotherapy, radiotherapy, and surgical resection.

Multiple Primary Tumors Originating From the Prostate and Colorectum A Clinical-Pathological and Therapeutic Challenge

Considering that the incidence of colorectal (CRC) and prostatic cancer (PC) increases with age, metachronous and synchronous tumors can often affect the same patient. Despite the importance of this subject for the diagnosis and management of oncologic patients, in medical literature the data are scarce. The aim of the study was to evaluate the incidence and the characteristics of double/multiple primary malignant tumors (D/MPMTs) with colorectal and prostatic origin, in patients admitted to a reference hospital in West Romania. A 4-year retrospective observational study (2016–2019) was conducted by analyzing the medical records of all patients admitted in the hospital. Demographic and clinical data, as well as tumor-related parameters, were extracted. We identified 413 consecutive hospitalized patients with PC, and 21 (5%) of them also had a primary CRC. At the time of diagnosis, the mean age of the patients with PC was 71.2 ± 6 years, and 71.8 ± 10 years for patients with CRC. Synchronous PC and CRC tumors were identified in 3/21 cases and metachronous tumors in 18/21 cases. Prostate cancer was the first tumor to be diagnosed in 13/18 cases and CRC in 5/18 cases. The most frequent subtype of PC was acinar adenocarcinoma (90%) and for CRC cases, conventional adenocarcinoma (90%). Prostate and colorectal cancers tend to co-occur in a single patient. The diagnosis of one of these two types of tumors should imply the screening for the other one, because these patients require a multidisciplinary and personalized approach.