Risk of primary non-breast cancer after female breast cancer by age at diagnosis

Unbalanced bidirectional causal association between thyroid cancer and ER-positive breast cancer: should we recommend screening for thyroid cancer in breast cancer patients?

BACKGROUND

The association between breast cancer (BC) and thyroid cancer (TC) has been studied in several epidemiological studies. However, the underlying causal relationship between them is not yet clear.

METHODS

The data from the latest large-sample genome-wide association studies (GWAS) of BC and TC were searched in the public GWAS database. The BC GWAS data included estrogen receptor (ER)-positive and negative subgroups. Two-way two-sample Mendelian Randomization (MR) was used to explore the potential causal relationship between BC and TC. Inverse variance weighting (IVW) and the MR-Egger method were used to combine the estimation of each single nucleotide variation (previous single nucleotide polymorphism). BC was taken as the result, and the effect of TC exposure was analyzed. Then, the effect of BC exposure on the result of TC was analyzed.

RESULTS

Both IVW and MR-Egger results indicated that gene-driven thyroid cancer does not cause estrogen receptor-positive breast cancer and is a protective factor (β = -1.203, SE = 4.663*10-4, P = 0.010). However, gene-driven estrogen receptor-positive breast cancer can lead to the development of thyroid cancer (β = 0.516, SE = 0.220, P = 0.019).

CONCLUSION

From the perspective of gene drive, people with TC are less likely to have ER-positive BC. In contrast, people with ER-positive BC are more likely to have TC. Therefore, it is recommended that patients with BC be screened regularly for TC.

Susceptibility Genes Associated with Multiple Primary Cancers

With advancements in treatment and screening techniques, we have been witnessing an era where more cancer survivors harbor multiple primary cancers (MPCs), affecting approximately one in six patients. Identifying MPCs is crucial for tumor staging and subsequent treatment choices. However, the current clinicopathological criteria for clinical application are limited and insufficient, making it challenging to differentiate them from recurrences or metastases. The emergence of next-generation sequencing (NGS) technology has provided a genetic perspective for defining multiple primary cancers. Researchers have found that, when considering multiple tumor pairs, it is crucial not only to examine well-known essential mutations like MLH1/MSH2, EGFR, PTEN, BRCA1/2, CHEK2, and TP53 mutations but also to explore certain pleiotropic loci. Moreover, specific deleterious mutations may serve as regulatory factors in second cancer development following treatment. This review aims to discuss these susceptibility genes and provide an explanation of their functions based on the signaling pathway background. Additionally, the association network between genetic signatures and different tumor pairs will be summarized.

Risk of second primary cancer among women in the Kaiser Permanente Breast Cancer Survivors Cohort

BACKGROUND

Breast cancer survivors are living longer due to early detection and advances in treatment and are at increased risk for second primary cancers. Comprehensive evaluation of second cancer risk among patients treated in recent decades is lacking.

METHODS

We identified 16,004 females diagnosed with a first primary stage I-III breast cancer between 1990 and 2016 (followed through 2017) and survived ≥ 1 year at Kaiser Permanente (KP) Colorado, Northwest, and Washington. Second cancer was defined as an invasive primary cancer diagnosed ≥ 12 months after the first primary breast cancer. Second cancer risk was evaluated for all cancers (excluding ipsilateral breast cancer) using standardized incidence ratios (SIRs), and a competing risk approach for cumulative incidence and hazard ratios (HRs) adjusted for KP center, treatment, age, and year of first cancer diagnosis.

RESULTS

Over a median follow-up of 6.2 years, 1,562 women developed second cancer. Breast cancer survivors had a 70% higher risk of any cancer (95%CI = 1.62-1.79) and 45% higher risk of non-breast cancer (95%CI = 1.37-1.54) compared with the general population. SIRs were highest for malignancies of the peritoneum (SIR = 3.44, 95%CI = 1.65-6.33), soft tissue (SIR = 3.32, 95%CI = 2.51-4.30), contralateral breast (SIR = 3.10, 95%CI = 2.82-3.40), and acute myeloid leukemia (SIR = 2.11, 95%CI = 1.18-3.48)/myelodysplastic syndrome (SIR = 3.25, 95%CI = 1.89-5.20). Women also had elevated risks for oral, colon, pancreas, lung, and uterine corpus cancer, melanoma, and non-Hodgkin lymphoma (SIR range = 1.31-1.97). Radiotherapy was associated with increased risk for all second cancers (HR = 1.13, 95%CI = 1.01-1.25) and soft tissue sarcoma (HR = 2.36, 95%CI = 1.17-4.78), chemotherapy with decreased risk for all second cancers (HR = 0.87, 95%CI = 0.78-0.98) and increased myelodysplastic syndrome risk (HR = 3.01, 95%CI = 1.01-8.94), and endocrine therapy with lower contralateral breast cancer risk (HR = 0.48, 95%CI = 0.38-0.60). Approximately 1 in 9 women who survived ≥ 1 year developed second cancer, 1 in 13 developed second non-breast cancer, and 1 in 30 developed contralateral breast cancer by 10 years. Trends in cumulative incidence declined for contralateral breast cancer but not for second non-breast cancers.

CONCLUSIONS

Elevated risks of second cancer among breast cancer survivors treated in recent decades suggests that heightened surveillance is warranted and continued efforts to reduce second cancers are needed.

Clinical characteristics and survival of second primary breast carcinoma with extramammary malignancies

Objectives

To investigate the characteristics, diagnosis, survival and prognosis of second primary breast carcinoma (SPBC).

Materials and methods

Records of 123 patients with SPBC in Tianjin Medical University Cancer Institute & Hospital between December 2002 and December 2020 were retrospectively reviewed. Clinical characteristics, imaging features and survival were analyzed and comparisons between SPBC and breast metastases (BM) were made.

Results

Of 67156 newly diagnosed breast cancer patients, 123 patients (0.18%) suffered previous extramammary primary malignancies. Of the 123 patients with SPBC, approximately 98.37%(121/123)were female. The median age was 55 years old (27-87). The average diameter of breast mass was 2.7 cm (0.5-10.7). Approximately 77.24% (95/123) of the patients presented with symptoms. The most common types of extramammary primary malignancies were thyroid, gynecological cancers, lung, and colorectal. Patients with the first primary malignant tumor of lung cancer were more likely to develop synchronous SPBC, and those with the first primary malignant tumor of ovarian cancer were more likely to develop metachronous SPBC. When comparing with BM, patients with SPBC were more often older (≥45 years old), at earlier stages (I/II), more microcalcification and less multiple breast masses in imaging. More than half (55.88%) of patients in the metachronous group developed primary breast cancer within 5 years after diagnosis of extramammary primary cancer. The median overall survival time was 71 months. Within 90 months, the prognosis of patients with synchronous SPBC was worse than that of patients with metachronous SPBC (p=0.014). Patients with BM had the worst outcome compared with patients with synchronous SPBC and metachronous SPBC (p<0.001).ER/PR-negative status, an interval of less than 6 months between the onset of two tumors, a late stage of first primary malignancy, and an age of diagnosis of first primary malignancy greater than 60 years predicted a worse prognosis for patients with SPBC.

Conclusion

The possibility of SPBC should be considered during the follow-up of patients with primary extramammary malignancy, especially within 5 years of the onset of the first tumor. The stage of first primary malignancy and the age at diagnosis of first primary malignancy have an impact on the prognosis of patients with SPBC.

Risks of second non-breast primaries following breast cancer in women: a systematic review and meta-analysis

BACKGROUND

Second primary cancer incidence is rising among breast cancer survivors. We examined the risks of non-breast second primaries, in combination and at specific cancer sites, through a systematic review and meta-analysis.

METHODS

We conducted a systematic search of PubMed, Embase, and Web of Science, seeking studies published by March 2022. We included studies that reported standardized incidence ratios (SIRs), with associated standard errors, assessing the combined risk of second non-breast primaries following breast cancer. We performed meta-analyses of combined second primary risks, stratifying by age, follow-up duration, and geographic region. We also assessed second primary risks at several specific sites, stratifying by age. The inverse variance method with DerSimonian-Laird estimators was used in all meta-analyses, assuming a random-effects model. Associated biases and study quality were evaluated using the Newcastle-Ottawa scale.

RESULTS

One prospective and twenty-seven retrospective cohort studies were identified. SIRs for second non-breast primaries combined ranged from 0.84 to 1.84. The summary SIR estimate was 1.24 (95% CI 1.14-1.36, I2: 99%). This varied by age: the estimate was 1.59 (95% CI 1.36-1.85) when breast cancer was diagnosed before age 50, which was significantly higher than in women first diagnosed at 50 or over (SIR: 1.13, 95% CI 1.01-1.36, p for difference: < 0.001). SPC risks were also significantly higher when based on Asian, rather than European, registries (Asia-SIR: 1.47, 95% CI 1.29-1.67. Europe-SIR: 1.16, 95% CI 1.04-1.28). There were significantly increased risks of second thyroid (SIR: 1.89, 95% CI 1.49-2.38), corpus uteri (SIR: 1.84, 95% CI 1.53-2.23), ovary (SIR: 1.53, 95% CI 1.35-1.73), kidney (SIR: 1.43, 95% CI 1.17-1.73), oesophagus (SIR: 1.39, 95% CI 1.26-1.55), skin (melanoma) (SIR: 1.34, 95% CI 1.18-1.52), blood (leukaemia) (SIR: 1.30, 95% CI 1.17-1.45), lung (SIR: 1.25, 95% CI 1.03-1.51), stomach (SIR: 1.23, 95% CI 1.12-1.36) and bladder (SIR: 1.15, 95% CI 1.05-1.26) primaries.

CONCLUSIONS

Breast cancer survivors are at significantly increased risk of second primaries at many sites. Risks are higher for those diagnosed with breast cancer before age 50 and in Asian breast cancer survivors compared to European breast cancer survivors. This study is limited by a lack of data on potentially confounding variables. The conclusions may inform clinical management decisions following breast cancer, although specific clinical recommendations lie outside the scope of this review.

Risk of primary haematologic cancers following incident non-metastatic breast cancer: A Danish population-based cohort study

BACKGROUND

Breast cancer survivors may have increased risk of subsequent haematologic cancer. We compared their risk of haematologic cancers with the general population during 38 years of follow-up.

METHODS

Using population-based Danish medical registries, we assembled a nationwide cohort of women diagnosed with incident non-metastatic breast cancer during 1980-2017, with follow-up through 2018. We compared breast cancer survivors with the general population by computing standardised incidence ratios (SIR) and 95% confidence intervals (CI).

RESULTS

Among 101,117 breast cancer survivors, we observed 815 incident haematologic cancers (median follow-up: 7.9 years). We observed excess risk of acute myeloid leukaemia (AML) (SIR: 1.65, 95%CI: 1.33-2.01), particularly in women who received chemotherapy (SIR: 3.33, 95%CI: 2.24-4.75) and premenopausal women (SIR: 3.23, 95%CI: 2.41-4.25). The risk of acute lymphoid leukaemia (ALL) was increased (SIR: 2.25, 95%CI: 1.29-3.66), whereas the risk of chronic lymphoid leukaemia (CLL) was decreased (SIR: 0.66, 95%CI: 0.53-0.82). An additional analysis showed elevated risk of CLL 0-6 months after breast cancer diagnosis (SIR: 3.00 95%CI: 1.75-4.80).

CONCLUSION

Compared to the general population, breast cancer survivors had elevated risk of AML, particularly when treated with chemotherapy. The risk of ALL was elevated, whereas the risk of CLL was lower. The higher risk of CLL in the first six months after diagnosis likely reflects surveillance bias-due to intensified diagnostic efforts at breast cancer diagnosis and treatment-prompting earlier detection. This has likely reduced the long-term risk of CLL in breast cancer survivors.

Risk of second primary cancer among breast cancer patients: A systematic review and meta-analysis

Objectives

The aim of this study was to estimate the extra risk of second primary cancer among breast cancer patients.

Methods and materials

This is a systematic review. A comprehensive search of literature was performed in PubMed, Web of Science, Cochrane library, and Scopus. The search included all published studies up to October 2022. This systematic review included studies published in the English language that reported the risk of second primary non-breast cancer [i.e., standardized incidence ratio (SIR)] among breast cancer patients older than 15 years. After evaluating the methodological quality of the selected studies, SIRs were pooled with consideration of heterogeneity among studies. The estimates were pooled by age and time since the diagnosis of primary breast cancer for both sexes (male and female). Age was categorized based on before 50 years and after 50 years, and time was categorized as duration of less than and more than 10 years, respectively.

Results

From 2,484 articles, 30 articles were eligible for inclusion in the systematic review and meta-analysis. The studies varied in terms of population, number of cases, study design, setting, and year of implementation of the research. The estimated SIR for men and women was 1.28 (95% CI: 1.18, 1.38) and 1.27 (95% CI: 1.15, 1.39), respectively. Women diagnosed with breast cancer before menopause [SIR: 1.52 (95% CI: 1.34, 1.71) vs. 1.21 (95% CI: 1.08, 1.34)] as well as women after 10 years since their breast cancer diagnosis [1.33 (95% CI: 1.22, 1.431) vs. 1.24 (95% CI: 1.10, 1.37)] were at a higher risk of developing second primary cancer. Among men, while there were no differences in risk based on age, with the increase of time, the risk of second primary cancer was reduced [SIR: 1.22 (95% CI: 1.12, 1.33) vs. 1.00 (95% CI: 0.79, 1.22)].

Conclusion

There is an extra risk of second primary cancer among breast cancer patients. The extra risk should be considered for further screening and preventive measures among this population.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=336062, identifier (CRD42022336062).

Links between Breast and Thyroid Cancer: Hormones, Genetic Susceptibility and Medical Interventions

Breast and thyroid glands are two common sites of female malignancies. Since the late 19th century, physicians have found that the cancers in either thyroid or mammary gland might increase the risk of second primary cancers in the other site. From then on, many observational clinical studies have confirmed the hypothesis and more than one theory has been developed to explain the phenomenon. Since the two glands both have secretory functions and are regulated by the hypothalamic-pituitary axis, they may share some common oncogenic molecular pathways. However, other risks factors, including medical interventions and hormones, are also observed to play a role. This article aims to provide a comprehensive review of the associations between the two cancers. The putative mechanisms, such as hormone alteration, autoimmune attack, genetic predisposition and other life-related factors are reviewed and discussed. Medical interventions, such as chemotherapy and radiotherapy, can also increase the risk of second primary cancers. This review will provide novel insights into the research designs, clinical managements and treatments of thyroid and breast cancer patients.

The co-occurrence of both breast- and differentiated thyroid cancer: incidence, association and clinical implications for daily practice

Background

Breast cancer (BC) and differentiated thyroid cancer (TC) are two common cancer types with the highest incidence in women. BC and TC can develop synchronous or metachronous and the occurrence of both is higher than expected by chance. This study aimed to examine the association between BC and TC in the Netherlands.

Methods

This is a retrospective cohort study during the period of 1989–2020 retrieved from the Netherlands Cancer Registry (NCR). Patients diagnosed with BC-TC and BC alone as control group and TC-BC and TC alone as control group were included. The primary outcome was the standardized incidence ratio (SIR) of BC-TC and TC-BC. Secondary outcomes included data on the demographics, type of malignancy, treatment and overall survival (OS).

Results

The incidence of TC among 318.002 women with BC (BC-TC) was 0.1% (423 patients) (SIR = 1.86 (95% CI: 1.40–2.32)) and the incidence of BC among 12,370 patients with TC (TC-BC) was 2.9% (355 patients) (SIR = 1.46 (95% CI: 1.09–1.83)). BC-TC patients were younger compared to the BC alone group at BC diagnosis (55 vs 60 years, p < 0.001). The age-adjusted odds ratio to develop TC was not significantly increased for patients who received chemotherapy and radiotherapy. Most TC cases were synchronous tumors after BC diagnosis (19%) with a TNM stage 1. Only 6% of the BC tumors after TC occurred synchronous with a TNM stage 1 in most cases. The OS of all groups was the most favorable in patients with both BC and TC compared to BC- and TC alone.

Conclusion and relevance

The SIR of TC after BC diagnosis and BC after TC diagnosis was higher than predicted based on the rates of the general population. TC and BC as second primary tumors were diagnosed in an early stage and did not affect overall survival. Therefore, Dutch women who have been treated for BC or TC require no special surveillance for their thyroid- and breast gland.

Temporal patterns of chronic disease incidence after breast cancer: a nationwide population-based cohort study

We conducted a retrospective cohort study to evaluate the temporal pattern of incidence of chronic conditions after developing breast cancer using a population-based national registry. We selected 84,969 women with newly diagnosed breast cancer between 2002 and 2016 and a 1:10 sample of age-matched non-breast cancer controls (N = 1,057,674). The main study exposure was incident breast cancer, considered as a time-varying exposure. The outcomes were incident cases of leukemia, endometrial cancer, myeloma, cardiomyopathy, osteoporosis, end stage renal disease (ESRD), pulmonary fibrosis, hypothyroidism, type 2 diabetes, hypertension and hyperlipidemia. The development of breast cancer was associated with a significantly increased risk of all outcomes analyzed except for ESRD and hypertension. The fully-adjusted risks of leukemia (HR 3.09; 95% CI 2.11–4.51), cardiomyopathy (HR 2.65; 95% CI 1.90–3.68), endometrial cancer (HR 3.53; 95% CI 2.76–4.53), hypothyroidism (HR 1.29; 95% CI 1.19–1.40), pulmonary fibrosis (HR 1.84; 95% CI 1.12–3.02), and hyperlipidemia (HR 1.24; 95% CI 1.20–1.28) remained significantly elevated after more than 5 years since diagnosis. Optimal care for breast cancer survivors requires close collaboration between oncologists and allied health care professionals to identify and manage the long-term morbidity and mortality associated with these chronic conditions.

The WID-BC-index identifies women with primary poor prognostic breast cancer based on DNA methylation in cervical samples

Genetic and non-genetic factors contribute to breast cancer development. An epigenome-based signature capturing these components in easily accessible samples could identify women at risk. Here, we analyse the DNA methylome in 2,818 cervical, 357 and 227 matched buccal and blood samples respectively, and 42 breast tissue samples from women with and without breast cancer. Utilising cervical liquid-based cytology samples, we develop the DNA methylation-based Women’s risk IDentification for Breast Cancer index (WID-BC-index) that identifies women with breast cancer with an AUROC (Area Under the Receiver Operator Characteristic) of 0.84 (95% CI: 0.80–0.88) and 0.81 (95% CI: 0.76–0.86) in internal and external validation sets, respectively. CpGs at progesterone receptor binding sites hypomethylated in normal breast tissue of women with breast cancer or in BRCA mutation carriers are also hypomethylated in cervical samples of women with poor prognostic breast cancer. Our data indicate that a systemic epigenetic programming defect is highly prevalent in women who develop breast cancer. Further studies validating the WID-BC-index may enable clinical implementation for monitoring breast cancer risk.

Breast cancer is most commonly diagnosed via a needle biopsy. In this study, the authors show that cervical samples from women with breast cancer have a methylation signature different to that of healthy controls.

The DNA methylome of cervical cells can predict the presence of ovarian cancer

The vast majority of epithelial ovarian cancer arises from tissues that are embryologically derived from the Müllerian Duct. Here, we demonstrate that a DNA methylation signature in easy-to-access Müllerian Duct-derived cervical cells from women with and without ovarian cancer (i.e. referred to as the Women's risk IDentification for Ovarian Cancer index or WID-OC-index) is capable of identifying women with an ovarian cancer in the absence of tumour DNA with an AUC of 0.76 and women with an endometrial cancer with an AUC of 0.81. This and the observation that the cervical cell WID-OC-index mimics the epigenetic program of those cells at risk of becoming cancerous in BRCA1/2 germline mutation carriers (i.e. mammary epithelium, fallopian tube fimbriae, prostate) further suggest that the epigenetic misprogramming of cervical cells is an indicator for cancer predisposition. This concept has the potential to advance the field of risk-stratified cancer screening and prevention.

Risks and cancer associations of metachronous and synchronous multiple primary cancers: a 25-year retrospective study

Background

The situation of patients developing multiple primary cancers is becoming more frequent and graver. This study investigated the risks of developing second primary cancers that are related to first primary cancers, and the interval times of synchronous and metachronous multiple primary cancers.

Patients and methods

Retrospective data were retrieved from 109,054 patients aged ≥18 who were diagnosed with a first solid cancer and registered at Siriraj Cancer Center between 1991 and 2015. A two-month period between first- and second- primary cancers was used to differentiate metachronous and synchronous multiple primary cancers. The combinations of subsequent cancers and relative risks (RRs) of having multiple primary cancers versus having single primary cancer for the top-ten first and second primary cancers were examined. The RR was adjusted for age of the first primary cancer. A survival analysis of the time to second-primary-cancer development was performed.

Results

Multiple primary cancers were found in 1785 (1.63%) patients. Most (70.87%) second primary cancers occurred after 2 months of first breast, skin, colorectal, lung, head and neck, liver, male genital cancer–prostate, thyroid, and female genital cancer–non-uterine cancers, resulting in those cancers being classified as metachronous multiple primary cancer. After adjustment for age at first diagnosis, head and neck cancers had the highest metachronous association with second esophageal cancers (RR, 25.06; 95% CI, 13.41–50.77). Prostate cancer and second colorectal cancer also demonstrated a high metachronous association (RR, 2.00; 95% CI, 1.25–3.05). A strong synchronous association was found between uterine and ovarian cancers (RR, 27.77; 95% CI, 17.97–43.63). The median time from the first uterine cancer to second-cancer development was 55 days.

Conclusions

The top-ten most frequent multiple primary cancers were the following: breast; liver; head and neck; colorectal; male genital cancer–prostate; skin; female genital cancer–uterine; thyroid; lung; and female genital cancer–non-uterine. Second primary cancers showed specific associations that depended on the first primary cancer. Physicians should be cognizant of the most common combinations and the interval times of metachronous and synchronous multiple primary cancers.

Genetic alterations associated with multiple primary malignancies

Breast cancer (BC) patients are frequently at risk of developing other malignancies following treatment. Although studies have been conducted to elucidate the etiology of multiple primary malignancies (MPM) after a BC diagnosis, few studies have investigated other previously diagnosed primary malignancies (OPPM) before BC. Here, genome‐wide profiling was used to identify potential driver DNA copy number alterations and somatic mutations that promote the development of MPMs. To compare the genomic profiles for two primary tumors (BC and OPPM) from the same patient, tumor pairs from 26 young women (≤50 years) diagnosed with one or more primary malignancies before breast cancer were analyzed. Malignant melanoma was the most frequent OPPM, followed by gynecologic‐ and hematologic malignancies. However, significantly more genetic alterations were detected in BC compared to the OPPM. BC also showed more genetic similarity as a group than the tumor pairs. Clonality testing showed that genetic alterations on chromosomes 1, 3, 16, and 19 were concordant in both tumors in 13 patients. TP53 mutations were also found to be prevalent in BC, MM, and HM. Although all samples were classified as genetically unstable, chromothripsis‐like patterns were primarily observed in BC. Taken together, few recurrent genetic alterations were identified in both tumor pairs that can explain the development of MPMs in the same patient. However, larger studies are warranted to further investigate key driver mutations associated with MPMs.

Risk factors and prediction of second primary cancer in primary female non-metastatic breast cancer survivors

This study aimed to investigate the risk factors of second primary cancer among female breast cancer (BC) survivors, with emphasis on the prediction of the individual risk conditioned on the patient's characteristics. We identified 208,474 BC patients diagnosed between 2004 and 2010 from the Surveillance, Epidemiology and End Results (SEER) database. Subdistribution proportional hazard model and competing-risk nomogram were used to explore the risk factors of second primary BC and non-BC, and to predict the 5- and 10-year probabilities of second primary BC. Model performance was evaluated via calibration curves and decision curve analysis. The overall 3-, 5-, and 10-year cumulative incidences for second primary BC were 0.9%, 1.6% and 4.4%, and for second primary non-BC were 2.3%, 3.9%, and 7.8%, respectively. Age over 70 years at diagnosis, black race, tumor size over 2 cm, negative hormone receptor, mixed histology, localized tumor, lumpectomy alone, and surgeries plus radiotherapy were significantly associated with increased risk of second BC. The risk of second non-BC was only related to age, race and tumor size. The proposed risk model as well as its nomogram was clinically beneficial to identify patients at high risk of developing second primary breast cancer.

Cancer surveillance and preventive services in a diverse sample of breast and colorectal cancer survivors

PURPOSE

Cancer survivors diagnosed at an early age remain at risk for cancer recurrence and other chronic diseases. This study assessed engagement in surveillance for recurrence, cancer screening, and other recommended preventive health services among breast and colorectal cancer survivors with early-onset disease (≤ 50 years) who were diagnosed in California.

METHODS

Breast and colorectal cancer survivors diagnosed with early-onset cancer between 1999 and 2009 were identified through the California Cancer Registry, the state-based cancer registry, and surveyed. Multivariable regression analyses were used to assess correlates of receipt of cancer surveillance, cancer screening, and other preventive health services.

RESULTS

Of the 497 survivors that were invited to participate in the study, 156 completed the survey for a response rate of 31%. The sample was 50 years of age on average (range 32-69 years) with a mean time since diagnosis of 9 years. The majority of the sample (71%) was a racial/ethnic minority (24% Latino, 15% African American, 29% Asian). Overall, 80% received appropriate surveillance for recurrence, and 72% received recommended screening for early detection of other cancers (breast, cervical, colorectal). Increasing age was associated with lower likelihood of early detection screening (adjusted odds ratio (aOR) 0.28, 95% confidence interval (CI) 0.11-0.69), and higher income was associated with a greater likelihood (aOR 4.89, 95% CI 1.62-14.81). Screening rates were highest for blood pressure (96%), cholesterol (86%), and diabetes (81%), followed by dental visits (64%) and flu vaccination (35%). Greater use of recommended preventive health services was associated with increasing age, female sex, higher education level, and having health insurance.

CONCLUSIONS

Although the majority of survivors received appropriate surveillance for recurrence, engagement in other preventive health services varied substantially.

IMPLICATIONS FOR CANCER SURVIVORS

Efforts are needed to address gaps in the use of recommended cancer screening and preventive health services among cancer survivors, particularly survivors with early-onset disease who may be at increased risk for additional cancers and common chronic conditions over their lifetime.

Previously diagnosed multiple primary malignancies in patients with breast carcinoma in Western Sweden between 2007 and 2018

PURPOSE

Multiple primary malignancies (MPMs) caused by breast cancer treatment are well described, but only few studies to date describe which other previous primary malignancies (OPPMs) occur before breast cancer. The purpose of the present study was to evaluate the prevalence of OPPMs in patients with breast cancer between 2007 and 2018 in Western Sweden.

METHODS

Patient selection was performed using both pathology reports at Sahlgrenska University Hospital (Sweden) and the Swedish Cancer Registry. All newly diagnosed breast cancer patients were screened for presence of OPPM.

RESULTS

In total, 8031 breast cancer patients were diagnosed at Sahlgrenska University Hospital between 2007 and 2018. The prevalence of breast cancer patients with OPPMs (n = 414) increased from on average 2.6% to 8.2% during this 12-year period and ranged from 17 to 59 patients annually. The most striking increase in prevalence was found among the gynecological tumors (endometrium and ovarian adenocarcinomas), malignant melanomas and gastrointestinal malignancies. These findings were validated using data of the Swedish Cancer Registry.

CONCLUSIONS

The overall survival rates for cancer patients have improved tremendously during the past 40 years, in part due to individually tailored therapies and screening programs. Our study revealed an increasing trend of OPPMs in breast cancer patients.

Uterine cancer in breast cancer survivors: a systematic review

PURPOSE

Epidemiological evidence on the risk factors for uterine/endometrial cancer in breast cancer (BCa) survivors is limited and inconsistent. Therefore, we critically reviewed and summarized available evidence related to the risk factors for uterine/endometrial cancer in BCa survivors.

METHODS

We conducted a literature search through PubMed, Web of Science Core Collection/Cited Reference Search, as well as through manual searches of the bibliographies of the articles identified in electronic searches. We included in this review studies that were published up to November 30, 2018 that were accessible in full-text format and were published in English.

RESULTS

Of the 27 eligible studies, 96% had > 700 participants, 74% were prospective cohorts, 70% originated outside of the US, 44% reported as having pre-/postmenopausal women, and 26% reported having racially heterogeneous populations. Risk factors positively associated with uterine/endometrial cancer risk among BCa survivors included age at BCa diagnosis > 50 years, African American race, greater BMI/weight gain, and Tamoxifen treatment. For other lifestyle, reproductive and clinical factors, associations were either not significant (parity) or inconsistent (HRT use, menopausal status, smoking status) or had limited evidence (alcohol intake, family history of cancer, age at first birth, oral contraceptive use, age at menopause, comorbidities).

CONCLUSION

We identified several methodological concerns and limitations across epidemiological studies on potential risk factors for uterine/endometrial cancer in BCa survivors, including lack of details on uterine/endometrial cancer case ascertainment, varying and imprecise definitions of important covariates, insufficient adjustment for potential confounders, and small numbers of uterine/endometrial cancer cases in the overall as well as stratified analyses. Based on the available evidence, older age and higher body weight measures appear to be a shared risk factor for uterine/endometrial cancer in the general population as well as in BCa survivors. In addition, there is suggestive evidence that African American BCa survivors have a higher risk of uterine/endometrial cancer as compared to their White counterparts. There is also evidence that Tamoxifen contributes to uterine/endometrial cancer in BCa survivors. Given limitations of existing studies, more thorough investigation of these associations is warranted to identify additional preventive strategies needed for BCa survivors to reduce uterine/endometrial cancer risk and improve overall survival.

Population-Based Cohort Study Reveals Distinct Associations Between Female Lung Cancer and Breast Cancer in Taiwan

PURPOSE

Associations between Asian lung cancer (LC) and breast cancer (BC) are unknown. This study evaluates associations between LC and BC in the Taiwan population.

METHODS

This study was based on the Taiwan National Health Insurance data and Taiwan Cancer Registry. The cohorts included women with newly diagnosed LC or BC between 2000 and 2011 and an age- and sex-stratified random sample as a noncancer comparison cohort during the same period. Cox proportional hazards regression analysis was used to determine the risks. The National Taiwan University Hospital (NTUH) cohort, which comprised patients with confirmed pathology diagnoses of double BC/LC, was reviewed.

RESULTS

In 32,824 women with LC, there were increased risks for synchronous BC in patients younger than age 50 years (hazard ratio, 5.80; 95% CI, 1.83 to 18.73), age 50 to 59 years (HR, 2.37; 95% CI, 1.02 to 5.54), and age 60 to 69 years (HR, 4.42; 95% CI, 1.91 to 10.2). In the 88,446 women with BC, there were increased risks for synchronous LC in patients age 40 to 59 years (HR, 5.86; 95% CI, 3.05 to 11.3) and older than 60 years (HR, 1.98; 95% CI, 1.04 to 3.77). In the 128-patient NTUH double LC/BC cohort, 77 (60%) had both cancers diagnosed within 5 years of each other.

CONCLUSION

LC is associated with an increased risk for synchronous BC in Taiwan and vice versa. Radiotherapy might not be a major risk factor for LC in BC survivors. Etiology for double LC/BC deserves additional exploration and cross-racial genomic studies.

Bilateral Salpingo-Oophorectomy Versus GnRH Analogue in the Adjuvant Treatment of Premenopausal Breast Cancer Patients: Cost-Effectiveness Evaluation of Breast Cancer Outcome, Ovarian Cancer Prevention and Treatment

BACKGROUND AND OBJECTIVE: There is no available evidence to recommend gonadotropin-releasing hormone (GnRH) analogue-based ovarian suppression versus bilateral salpingo-oophorectomy (BSO) in the adjuvant treatment of early breast cancer, since the two approaches are considered equivalent in terms of oncologic outcome. The role of surgical ovarian ablation has been revitalized based on the advances of minimally invasive surgery, and a better understanding of clinical and molecular basis of hereditary breast/ovarian cancer syndromes. The aim of this study is to analyze the cost-effectiveness of laparoscopic BSO and GnRH analogue administration in patients aged 40-49 years with hormone-sensitive breast cancer.

METHODS

A probabilistic decision tree model was developed to evaluate costs and outcomes of ovarian ablation through laparoscopic BSO, or ovarian suppression through monthly injections of GnRH analogue. Results were expressed as incremental costs per quality-adjusted life years (QALYs) gained.

RESULTS

Laparoscopic BSO strategy was associated with a lower mean total cost per patient than GnRH treatment, and considering the difference in terms of QALYs, the incremental effectiveness did not demonstrate a notable difference between the two approaches. From the National Health Service perspective, and for a time horizon of 5 years, laparoscopic BSO was the dominant option compared to GnRH treatment; laparoscopic BSO was less expensive than GnRH, €2385 [95% confidence interval (CI) = 2044, 2753] vs €7093 (95% CI = 3409, 12,105), respectively, and more effective.

CONCLUSION

Surgical ovarian ablation is more cost-effective than GnRH administration in the adjuvant treatment of hormone-sensitive breast cancer patients aged 40-49 years, and the advantage of preventing ovarian cancer through laparoscopic BSO should be considered.

The clinicopathological features of second primary cancer in patients with prior breast cancer

Nowadays, the risk of developing second primary cancers among women diagnosed with prior breast cancer represents a public health issue worldwide.Twenty-eight cases of the primary breast cancer with the multiple primary cancers (MPC) between 2008 and 2015 at our hospital were retrospectively analyzed in regards to age of patients, family history, interval time of the 2 cancers, and survival time of these patients.A total 28 cases were analyzed, at the mean age of 44.57 years at the diagnosis of the first primary cancer. The most common primary cancer in these breast cancer patients was contralateral breast cancer. Of 28 patients with breast cancer, 16 developed a second malignant tumor of the opposite breast, there were no significant difference both median age at first breast cancer and second breast cancer (P > .05). The difference of interval time of 2 cancers also had no statistical significance. There was no statistically significant difference in overall survival between the bilateral primary breast cancers (BPBC) group and the group of breast cancer patients who diagnosed with another cancer (P > .05). If we grouped patients age of diagnosed with the first cancer (<45, ≥45 years), no statistical different between 2 groups (P > .05). However, the survival time with positive-node patients was lower than in patients with node-negative, the difference had a notable significant difference (P < .01). And there are 3 cases had a positive family history for malignant tumor in the form of first-degree relative.Multiple primary carcinoma in patients with prior breast cancer is not the influencing factor of prognosis. It is crucial to detect, diagnose, and treat cancers at their early stage for improving the cure rate of cancer and the survival rate of patients.

The Breast-Thyroid Cancer Link: A Systematic Review and Meta-analysis

Rates of thyroid cancer in women with a history of breast cancer are higher than expected. Similarly, rates of breast cancer in those with a history of thyroid cancer are increased. Explanations for these associations include detection bias, shared hormonal risk factors, treatment effect, and genetic susceptibility. With increasing numbers of breast and thyroid cancer survivors, clinicians should be particularly cognizant of this association. Here, we perform a systematic review and meta-analysis of the literature utilizing PubMed and Scopus search engines to identify all publications studying the incidence of breast cancer as a secondary malignancy following a diagnosis of thyroid cancer or thyroid cancer following a diagnosis of breast cancer. This demonstrated an increased risk of thyroid cancer as a secondary malignancy following breast cancer [OR = 1.55; 95% confidence interval (CI), 1.44-1.67] and an increased risk of breast cancer as a secondary malignancy following thyroid cancer (OR = 1.18; 95% CI, 1.09-1.26). There is a clear increase in the odds of developing either thyroid or breast cancer as a secondary malignancy after diagnosis with the other. Here, we review this association and current hypothesis as to the cause of this correlation.

Blue Lymphangitis of the Breast after Breast Cancer: Case Report

Carcinomatous lymphangitis accounts for 5% of all skin metastases, but blue lymphangitis of the breast has never been described. We report a case of blue lymphangitis of the breast in a patient 11 years after treatment for ipsilateral breast cancer that was in full remission. Breast examination and imaging showed no other abnormalities. Skin biopsy revealed a carcinomatous-pigmented infiltration corresponding to melanoma metastasis, which helped highlight a primitive right flank injury. This case report emphasizes that a full body exam should always be performed with unusual presentation of breast cancer and reiterates the indispensable place of histology before any diagnosis.

Risk of Second Non-Breast Primary Cancer in Male and Female Breast Cancer Patients: A Population-Based Cohort Study

Female breast cancer patients have an increased risk of developing subsequent malignant diseases, but this issue is rarely discussed in regards to male breast cancer patients. Thus, we conducted a national survey that included 100,915 female and 578 male breast cancer patients to investigate the risk of second primary malignancy (SPM). During a follow-up period that included 529,782 person-years, 3,153 cases of SPM developed. Compared with the general population, the standardized incidence ratio (SIR) of SPM in breast cancer patients was 1.51 [95% confidence interval (CI): 1.46-1.56]. The observed risk was significantly higher in male patients (SIR 2.17, 95% CI 1.70-2.73) and in patients whose age at breast cancer diagnosis was 40 years or younger (SIR 3.39, 95% CI 2.80-4.07), comparing to age-matched general population. Compared with the overall female population, the SIRs of female breast cancer patients with uterine (SIR: 2.66, 95% CI: 2.37-2.98), thyroid (SIR: 2.30, 95% CI: 2.02-2.62), and bone and soft tissue (SIR: 2.16, 95% CI: 1.56-2.91) cancers were significantly increased. Male breast cancer patients also displayed significantly higher SIRs for thyroid (SIR: 13.2, 95% CI: 1.60-47.69), skin (SIR: 8.24, 95% CI: 3.02-17.94) and head and neck (SIR: 4.41, 95% CI: 2.35-7.54) cancers. Among breast cancer patients, risk factors significantly associated with SPM included male gender, older age, chemotherapy treatment and comorbidity with liver cirrhosis. From our analysis, we concluded that the risk of SPM was significantly higher for both male and female breast cancer patients compared with the general population, suggesting that more intensive surveillance may be needed, especially in high-risk patients.

Risk of Second Primary Malignancy in Breast Cancer Survivors: A Nested Population-Based Case-Control Study

PURPOSE

Evolving therapies have improved the prognoses of patients with breast cancer; and currently, the number of long-term survivors is continuously increasing. However, these patients are at increased risk of developing a second cancer. Thus, late side effects are becoming an important issue. In this study, we aimed to investigate whether patient and tumor characteristics, and treatment type correlate with secondary tumor risk.

METHODS

This case-control study included 305 patients with a diagnosed second malignancy after almost 6 months after the diagnosis of primary breast cancer and 1,525 controls (ratio 1:5 of cases to controls) from a population-based cohort of 6,325 women. The control patients were randomly selected from the cohort and matched to the cases according to age at diagnosis, calendar period of diagnosis, disease stage, and time of follow-up.

RESULTS

BRCA1 or BRCA2 mutation, human epidermal growth factor receptor 2 (HER2)+ status, chemotherapy, and radiotherapy were related to increased risk of developing a second cancer, whereas hormonotherapy showed a protective effect. Chemotherapy, radiotherapy, and estrogenic receptor level <10% increased the risk of controlateral breast cancer. HER2+ status increased the risk of digestive system and thyroid tumors, while BRCA1 or BRCA2 mutation increased the risk of cancer in the genital system.

CONCLUSION

Breast cancer survivors are exposed to an excess of risk of developing a second primary cancer. The development of excess of malignancies may be related either to patient and tumor characteristics, such as BRCA1 or BRCA2 mutation and HER2+ status, or to treatments factors.

Characteristics and Survival of Breast Cancer Patients with Multiple Synchronous or Metachronous Primary Cancers

PURPOSE

Newly developed extra-mammary multiple primary cancers (MPCs) are an issue of concern when considering the management of breast cancer survivors. This study aimed to investigate the prevalence of MPCs and to evaluate the implications of MPCs on the survival of breast cancer patients.

MATERIALS AND METHODS

A total of 8204 patients who underwent surgery at Severance Hospital between 1990 and 2012 were retrospectively selected. Clinicopathologic features and survival over follow-up periods of ≤5 and >5 years were investigated using univariate and multivariate analyses.

RESULTS

During a mean follow-up of 67.3 months, 962 MPCs in 858 patients (10.5%) were detected. Synchronous and metachronous MPCs were identified in 23.8% and 79.0% of patients, respectively. Thyroid cancer was the most prevalent, and the second most common was gynecologic cancer. At ≤5 years, patients with MPCs were older and demonstrated significantly worse survival despite a higher proportion of patients with lower-stage MPCs. Nevertheless, an increased risk of death in patients with MPCs did not reach statistical significance at >5 years. The causes of death in many of the patients with MPCs were not related to breast cancer. Stage-matched analysis revealed that the implications of MPCs on survival were more evident in the early stages of breast disease.

CONCLUSION

Breast cancer patients with MPCs showed worse survival, especially when early-stage disease was identified. Therefore, it is necessary to follow screening programs in breast cancer survivors and to establish guidelines for improving prognosis and quality of life.

Clinicopathological and Immunohistochemical Characteristics in Male Breast Cancer: A Retrospective Case Series

BACKGROUND

Due to its rarity, male breast cancer (mBC) remains an inadequately characterized disease, and current evidence for treatment derives from female breast cancer (FBC).

METHODS

We retrospectively analyzed the clinicopathological characteristics, treatment patterns, and outcomes of mBCs treated from 2000 to 2013.

RESULTS

From a total of 97 patients with mBC, 6 (6.2%) with ductal in situ carcinoma were excluded, and 91 patients with invasive carcinoma were analyzed. Median age was 65 years (range: 25-87 years). Estrogen receptors were positive in 88 patients (96.7%), and progesterone receptors were positive in 84 patients (92.3%). HER-2 was overexpressed in 13 of 85 patients (16%). Median follow-up was 51.5 months (range: 0.5-219.3 months). Five-year progression-free survival (PFS) was 50%, whereas overall survival (OS) was 68.1%. Patients with grades 1 and 2 presented 5-year PFS of 71% versus 22.5% for patients with grade 3 disease; 5-year OS was 85.7% for patients with grades 1 and 2 versus 53.3% of patients with grade 3. Ki-67 score >20% and adjuvant chemotherapy were also statistically significant for OS on univariate analyses. Twenty-six of 87 patients (29.8%) experienced recurrent disease and 16 of 91 patients (17.6%) developed a second neoplasia.

CONCLUSION

Male breast cancer shows different biological patterns compared with FBC, with higher positive hormone-receptor status and lower HER-2 overexpression. Grade 3 and Ki-67 >20% were associated with shorter OS.

IMPLICATIONS FOR PRACTICE

There is little evidence that prognostic features established in female breast cancer, such as grading and Ki-67 labeling index, could be applied to male breast cancer as well. This study found that grade 3 was associated with shorter overall survival and a trend for Ki-67 >20%; this could help in choosing the best treatment option in the adjuvant setting. Many questions remain regarding the impact of HER-2 positivity on survival and treatment with adjuvant anti-HER-2 therapy. Regarding metastatic male breast cancer, the results suggest that common regimens of chemo-, endocrine and immunotherapy used in female breast cancer are safe and effective for men. Male breast cancer patients show a higher incidence of second primary tumors, especially prostate and colon cancers and should therefore be carefully monitored.

Risk of second cancers cancer after a first primary breast cancer: a systematic review and meta-analysis

OBJECTIVE

To examine the scientific evidence and the risk of second primary cancers in women diagnosed with a first primary breast cancer.

METHODS

The literature was searched in Pubmed and Embase and included studies published up to June 2013, using population-based data and IARC/AICR codification rules for multiple primary cancers. A qualitative synthesis was carried out and the methodological quality of the studies evaluated. Standardised incidence ratios (SIRs) on second cancer risk, weighted by the standard error of each study, were pooled using fixed and random effects models. SIRs were also pooled by age at diagnosis (<50 and ≥ 50 years), and time since diagnosis of the first breast cancer (<10 and ≥ 10 years).

RESULTS

15 out of 710 articles fulfilled the inclusion criteria. All of them were retrospective cohort studies either population-based (13 studies) or hospital-based studies (2 studies). The studies varied with respect to number of cases, selection criteria, definition of multiple primary cancers, and the second cancer sites included. SIRs reported in these studies for all cancers combined varied from 1.0 to 1.4. The pooled SIR estimate for second cancer risk was 1.17 (95% CI: 1.10-1.25). By age groups, SIR estimates were 1.51 (95% CI: 1.35-1.70) for women younger than 50 years and 1.11 (95% CI: 1.02-1.21) for those who were older. Women with breast cancer are at risk of second cancers within the first 10 years after the first breast cancer diagnosis (SIR: 1.19; 95% CI: 1.06-1.33), and thereafter (SIR: 1.26; 95% CI: 1.05-1.52).

CONCLUSION

This higher risk of second cancers in women diagnosed with a first primary breast cancer with respect to the general population emphasises the importance of prevention and control policies aimed at reducing incidence of second cancers.

Association between melanocytic nevi and risk of breast diseases: The French E3N prospective cohort

BACKGROUND

While melanocytic nevi have been associated with genetic factors and childhood sun exposure, several observations also suggest a potential hormonal influence on nevi. To test the hypothesis that nevi are associated with breast tumor risk, we explored the relationships between number of nevi and benign and malignant breast disease risk.

METHODS AND FINDINGS

We prospectively analyzed data from E3N, a cohort of French women aged 40-65 y at inclusion in 1990. Number of nevi was collected at inclusion. Hazard ratios (HRs) for breast cancer and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression models. Associations of number of nevi with personal history of benign breast disease (BBD) and family history of breast cancer were estimated using logistic regression. Over the period 15 June 1990-15 June 2008, 5,956 incident breast cancer cases (including 5,245 invasive tumors) were ascertained among 89,902 women. In models adjusted for age, education, and known breast cancer risk factors, women with "very many" nevi had a significantly higher breast cancer risk (HR = 1.13, 95% CI = 1.01-1.27 versus "none"; ptrend = 0.04), although significance was lost after adjustment for personal history of BBD or family history of breast cancer. The 10-y absolute risk of invasive breast cancer increased from 3,749 per 100,000 women without nevi to 4,124 (95% CI = 3,674-4,649) per 100,000 women with "very many" nevi. The association was restricted to premenopausal women (HR = 1.40, ptrend = 0.01), even after full adjustment (HR = 1.34, ptrend = 0.03; phomogeneity = 0.04), but did not differ according to breast cancer type or hormone receptor status. In addition, we observed significantly positive dose-response relationships between number of nevi and history of biopsy-confirmed BBD (n = 5,169; ptrend<0.0001) and family history of breast cancer in first-degree relatives (n = 7,472; ptrend = 0.0003). The main limitations of our study include self-report of number of nevi using a qualitative scale, and self-reported history of biopsied BBD.

CONCLUSIONS

Our findings suggest associations between number of nevi and the risk of premenopausal breast cancer, BBD, and family history of breast cancer. More research is warranted to elucidate these relationships and to understand their underlying mechanisms.

Mortality and incidence of new primary cancers in men with prostate cancer: a Danish population-based cohort study

BACKGROUND

Prostate cancer (PC) survivors may have an increased risk of new primary cancers (NPCs) due to shared risk factors or PC-directed treatments.

METHODS

Using Danish registries, we conducted a cohort study of men with (n=30,220) and without PC (n=151,100) (comparators), matched 1:5 on age and PC diagnosis/index date. We computed incidence rates of NPCs per 10,000 person years (PY) and associated 95% confidence intervals (CI), and used Cox proportional hazards regression to compute hazard ratios (HRs) and 95%CI, adjusting for comorbidities. In order to obviate any impact of shorter survival among prostate cancer patients, we censored comparator patients when the matched prostate cancer patient died or was censored.

RESULTS

Follow-up spanned 113,487PY and 462,982PY in the PC and comparison cohorts, respectively. 65% of the cohorts were aged >70 years at diagnosis. Among PC patients, 51% had distant/unspecified stage, and 63% had surgery as primary treatment. The PC cohort had lower incidence of NPCs than their comparators. The adjusted HR of NPC among men with PC versus the comparators was 0.84 (95%CI=0.80, 0.88). Lowest HRs were among older men, those with distant stage, and were particularly evident for cancers of the brain, liver, pancreas, respiratory, upper gastrointestinal, and urinary systems.

CONCLUSIONS

We find no evidence of an increased risk of NPCs among men with PC. The deficit of NPCs among men with PC may be a true effect but is more likely due to lower levels of risk factors (e.g., smoking) in PC patients versus comparators, clinical consideration of cancers at new organs as metastases rather than new primaries, or under-recording/under-reporting of NPCs among PC patients.

Risk of second primary cancer among women with breast cancer: a population-based study in Granada (Spain)

OBJECTIVE

The higher risk of developing new cancers in breast cancer survivors is a public health concern. Our aim was to examine risk of second primary cancers among women diagnosed with breast cancer.

METHODS

We studied two cohorts of female cancer patients identified in a population-based cancer registry in Granada (Spain): women first diagnosed with a primary breast cancer (n=5897) and those with a primary cancer in another site (n=22,814), followed during 1985-2007 for second cancers and breast cancer occurrence, respectively. We used Standardized Incidence Ratios (SIRs) to estimate second cancer risk by age (<50y, ≥50y), time since diagnosis (≤5y, >5y) and calendar periods (≤1995, >1996). SIR for breast cancer was calculated in the second cohort.

RESULTS

The risk of developing second cancers (n=314) was 39% higher (95% CI=1.23-1.54) among breast cancer patients, and particularly high among women under 50 (SIR=1.96, 95% CI=1.48-2.44). Excess risk for endometrial cancer (SIR=3.04, 95% CI=2.14-3.94) was statistically significant and remained so in women over 50. Younger women were at higher risk of second ovarian cancer (SIR=4.90, 95% CI=1.27-8.53). Increased SIRs were observed during the first five years after breast cancer diagnosis, whereas SIRs decreased thereafter. Breast cancer incidence (n=171) was not higher among women previously diagnosed with other cancer types (SIR=0.86, 95% CI=0.74-1.00).

CONCLUSION

Women diagnosed with breast cancer have a higher incidence of second primary cancers, particularly of endometrial cancer in women over 50 at diagnosis, and ovarian cancer in younger women. These findings may be explained by treatment-related effects or shared risk factors.

Multiple primary cancers among colorectal cancer survivors in Queensland, Australia, 1996-2007

PURPOSE

To quantify the demographic and clinical factors associated with an increased risk of multiple primary cancers (MPCs) among colorectal cancer survivors.

METHODS

Standardized incidence ratios for MPCs were calculated for residents of Queensland, Australia, who were diagnosed with a first primary colorectal cancer between 1996 and 2005 and survived for at least 2 months. Relative risk ratios were calculated for all MPCs combined and selected individual sites using multivariate Poisson models.

RESULTS

A total of 1,615 MPCs were observed among 15,755 study patients. The cohort had a significant excess risk of developing subsequent colorectal (SIR = 1.47, 95 % CI 1.30-1.66) or non-colorectal (SIR = 1.24, 95 % CI 1.18-1.31) cancers relative to the incidence of cancer in the general population. Age at initial diagnosis, follow-up time, initial colorectal subsite, and surgical treatment were independently associated (p < 0.01) with the overall risk of developing MPCs after adjustment. The relative risk ratio was 1.23 (95 % CI 1.07-1.41) for those aged 20-59 years compared with the 70-79 age group and 0.82 (95 % CI 0.72-0.92) for 1-5-year follow-up relative to the first year. The likelihood of being diagnosed with a MPC was 33 % higher (95 % CI 1.12-1.56) for surgically treated patients and 45 % higher (95 % CI 1.29-1.64) after proximal colon cancers relative to rectal cancer.

CONCLUSIONS

While these population-based results do not incorporate all possible risk factors, they form an important foundation from which to further investigate the etiological causes that result in the development of MPCs among colorectal cancer survivors.