Second primary neoplasms after 19281 endocrine gland tumours: aetiological links?

The Incidence of Cancers in Patients With Nonfunctional Adrenal Tumors: A Swedish Population-Based National Cohort Study

Context

It is unclear if nonfunctional adrenal tumors (NFAT) are associated with higher cancer incidence.

Objective

To analyze the cancer incidence in patients with NFAT.

Methods

In this national register-based retrospective cohort study, consecutive patients with NFAT identified in Sweden 2005-2019 and matched control individuals without adrenal tumors were followed up to 15 years. Outcome data were collected from national registers and adjusted for confounders. Both cases and controls were followed until newly diagnosed malignancy, death, or until 2019. Individuals with adrenal hormonal excess or prior malignancy were excluded.

Results

Among 17 726 cases, 10 777 (60.8%) were women, and the median age was 65 (IQR, 57-73) years. Among 124 366 controls, 69 514 (55.9%) were women, and the median age was 66 (IQR, 58-73) years. The incidence of any cancer was higher in patients with NFAT compared to controls (hazard ratio [HR] 1.35 95% CI 1.29-1.40; adjusted HR 1.31, 95% CI 1.26-1.37). NFAT was associated with a higher incidence of adrenal, thyroid, lung, stomach and small intestine, kidney, pancreatic, breast, and colorectal cancer. Sensitivity analyses did not change the overall results, but associations were not significantly increased after adjustment in patients with NFAT and appendicitis or gallbladder/biliary tract/pancreas disorders. Cancer incidence may have been underestimated by adjusting for unclear and benign tumors.

Conclusion

The incidence of cancer was increased in patients with NFAT. Long-term follow-up may be indicated.

Risk of Malignant Neoplasm in Patients with Primary Hyperparathyroidism: A Systematic Review and Meta-analysis

This study aimed to evaluate the prevalence and risk of malignant neoplasm in primary hyperparathyroidism (PHPT) patients. Potentially eligible studies were retrieved from PubMed and Embase databases from inception to November 2023 using search strategy consisting of terms for "Primary hyperparathyroidism" and "Malignant neoplasm". Eligible study must report prevalence of malignant neoplasm among patients with PHPT or compare the risk of malignant neoplasm between patients with PHPT and comparators. Point estimates with standard errors were extracted from each study and combined using the generic inverse variance method.A total of 11,926 articles were identified. After two rounds of systematic review, 50 studies were included. The meta-analysis revealed that pooled prevalence rates of overall cancer was 0.19 (95%CI: 0.13-0.25; I2 94%). The two most prevalent types of malignancy among patients with PHPT ware papillary thyroid cancer (pooled prevalence: 0.07; 95%CI: 0.06-0.08; I2 85%) and breast cancer (pooled prevalence: 0.05; 95%CI: 0.03-0.07; I2 87%). Subgroup analysis of studies focusing on patients undergoing parathyroidectomy reported a fourfold higher prevalence of papillary thyroid cancer than the remaining studies (0.08 versus 0.02). The meta-analysis of cohort studies found a significant association between PHPT and overall cancer with the pooled risk ratio of 1.28 (95%CI: 1.23-1.33; I2 66.9%).We found that the pooled prevalence of malignant neoplasm in PHPT was 19%, with papillary thyroid cancer and breast cancer being the most prevalent types. The meta-analysis of cohort studies showed that patient with PHPT carried an approximately 28% increased risk of malignancy.

Second Primary Cancer Among Patients With Papillary Thyroid Carcinoma Following the Chernobyl Disaster

Importance

To our knowledge, there are no complete population-based studies of the risks of developing second malignant tumors after papillary thyroid carcinoma (PTC) in patients following the Chernobyl nuclear accident.

Objective

To study the risk of second primary cancers in patients with PTC after the Chernobyl disaster.

Design, Setting, and Participants

This was a retrospective cohort study conducted in the Republic of Belarus over a 31-year time frame evaluating patients with primary PTC and second malignant tumors. Personal data from the Belarussian Cancer Registry were used in the investigation, and only second primary cancers were included in the analysis. Patients were observed from January 1, 1990, to December 31, 2021, for the establishment of second primary malignant tumors.

Main Outcomes and Measures

For analysis, synchronous and metachronous tumors were grouped into 1 group (second primary cancer group). If the patient had more than 2 cancers, they were observed until development of a second tumor and, subsequently, the development of a third tumor. The starting point for calculating the number of person-years was the date of thyroid cancer diagnosis. The end point for calculating the number of person-years was the date of diagnosis of the second primary malignant tumor, the date of death, the date of the last visit of the patient, or December 31, 2021 (the end the of study period). The incidence of a second primary malignant tumor with PTC was calculated for the study groups using standardized incidence ratios.

Results

Of the 30 568 patients with a primary PTC included in this study, 2820 (9.2%) developed a second malignant tumor (2204 women and 616 men); the mean (SD) age of all patients at time of the primary cancer was 53.9 (12.6) years and at time of the secondary cancer was 61.5 (11.8) years. Overall, the standardized incidence ratio was statistically significant for all types of cancer (1.25; 95% CI, 1.21-1.30), including solid malignant tumors (1.20; 95% CI, 1.15-1.25) and all leukemias (1.61; 95% CI, 2.17-2.13). Cancers of the digestive system (466 cases [21.1%]), genital organs (376 cases [17.1%]), and breasts (603 cases [27.4%]) were the most prevalent second primary tumors in women following PTC. Second primary tumors of the gastrointestinal tract (146 cases [27.7%]), genitourinary system (139 cases [22.6%]), and urinary tract (139 cases [22.6%]) were the most prevalent in men. Urinary tract cancers (307 cases [10.9%]) and gastrointestinal tumors (612 cases [21.4%]) were the most prevalent second primary tumors overall.

Conclusions and Relevance

This cohort study reports the increased incidence of solid secondary tumors in men and women over a 31-year time frame after the Chernobyl disaster. Moreover, there was a statistically significant increased risk of second tumors of the breast, colon, rectum, mesothelium, eye, adnexa, meninges, and adrenal glands as well as Kaposi sarcoma. These data might have an effect on the follow-up of this cohort of patients to detect secondary malignant tumors at an early stage.

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.

Benign Adrenocortical Tumors and the Detection of Nonadrenal Neoplasia

CONTEXT

Patients with adrenocortical tumors have been frequently observed to have nonadrenal neoplasia.

OBJECTIVE

To investigate whether patients with benign adrenocortical tumors have a higher likelihood of having nonadrenal neoplasia detected.

DESIGN AND PARTICIPANTS

Case-control study of patients with benign adrenocortical tumors (cases; n = 400) and normal adrenal glands (controls; n = 400), who underwent repeated abdominal cross-sectional imaging.

MAIN OUTCOMES

Primary analyses: association between case-control status and benign abdominal neoplasia detected via cross-sectional imaging. Secondary analyses: association between case-control status and tumors detected via other imaging modalities.

RESULTS

The mean interval of abdominal imaging was 4.7 (SD = 3.8) years for cases and 5.9 (4.8) years for controls. Cases were more likely to have detected intraductal papillary mucinous neoplasms (IPMNs) of the pancreas (8.5% vs. 4.5%, adjusted OR = 2.22, 95% CI (1.11, 4.63)) compared with controls. In secondary analyses, cases were more likely to have detected thyroid nodules (25.5% vs. 17.0%, adjusted OR = 1.77, 95% CI (1.15, 2.74)), hyperparathyroidism or parathyroid adenomas (3.5% vs. 1.3%, adjusted OR = 3.00, 95% CI (1.00, 11.64)), benign breast masses (6.0% vs. 3.3%, adjusted OR = 3.25, 95% CI (1.28, 8.78)), and benign prostatic hyperplasia (20.5% vs. 5.3%, adjusted OR = 3.20, 95% CI (1.14, 10.60)). Using a composite outcome, cases had higher odds of detection of the composite of IPMN, thyroid nodules, parathyroid tumors, benign breast masses, and prostate hyperplasia (adjusted OR = 2.36, 95% CI: 1.60, 3.50) when compared with controls.

CONCLUSIONS

Patients with benign adrenocortical tumors had higher odds of detected pancreatic IPMN, as well as thyroid nodules, parathyroid tumors, benign breast masses, and prostate hyperplasia compared with patients with normal adrenal glands. These associations may have important implications for patient care and healthcare economics, regardless of whether they reflect incidental discoveries due to imaging detection or frequency bias, or a common risk for developing multiple neoplasia.

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.

Association of urothelial carcinoma of the renal pelvis with papillary and medullary thyroid carcinomas. A new sporadic neoplastic syndrome?

We describe 2 adult women (72 and 54 years), 1 with a low-grade noninvasive papillary urothelial carcinoma of the renal pelvis, who 14 years later developed a papillary carcinoma in 1 thyroid lobe and a medullary carcinoma in the contralateral lobe. Both neoplasms were similar in size and appeared symmetrical. Despite its small size, the medullary carcinoma metastasized in multiple cervical lymph nodes. The second patient had a high-grade invasive papillary urothelial carcinoma of the renal pelvis that infiltrated the renal parenchyma and metastasized in one of the lungs. Five months later, a papillary carcinoma was discovered in the thyroid gland. The 2 papillary thyroid carcinomas were of the follicular variant. Adjacent to 1 papillary carcinoma, there was a dominant nodule of a colloid and adenomatous goiter. The medullary carcinoma contained stromal amyloid and was immunoreactive for calcitonin and carcinoembryonic antigen. There was no C-cell hyperplasia (medullary carcinoma in situ). The 2 patients are alive, 1 is living with pulmonary metastasis from the high-grade urothelial carcinoma. Twelve cases of this neoplastic association were registered in the Survey, Epidemiology, and End Results Program from 1980 to 2009. We believe that the combination of these unusual neoplasms in the same patient may represent a new sporadic neoplastic syndrome.

Familial risk of small intestinal carcinoid and adenocarcinoma

BACKGROUND & AIMS

Small intestinal cancer (SIC) is rare, and its etiology is poorly understood. We compared clusters of families with SICs of different histologic subtypes.

METHODS

By using the nationwide family cancer data sets of Sweden and Finland, we identified a cohort of 9964 first-degree relatives of 1799 patients with SIC, diagnosed from 1961 through 2009. Data were collected from time periods as long as 47 years (mean, 35.4 y), and cancer incidence was determined. Standardized incidence ratios (SIRs) were calculated and stratified by sex, age, time period, and cancer type, using the incidence rates for the entire national population as the reference.

RESULTS

Among the 1799 SIC cases, 1.1% had a sibling with SIC, so the SIR was 11.8 (95% confidence interval [CI], 7.2-18.2); 1.1% had a parent or child with SIC (SIR, 3.5; 95% CI, 2.0-5.6). The SIR of concordant carcinoid histology of SIC among siblings was 28.4 (95% CI, 14.7-49.6; n = 12) and in parent-child pairs was 9.9 (95% CI, 5.4-16.6; n = 14). The familial risk of concordant histologic subtypes increased for siblings diagnosed with adenocarcinoma, but only 2 familial cases were identified. In family members of patients with SIC of the adenocarcinoma subtype, risks of colorectal and bladder cancer were modestly but significantly increased compared with the general population. Family members of patients with SIC of the carcinoid subtype had an increased risk for kidney cancer and polycythemia vera.

CONCLUSIONS

Based on data from our population-based study, first-degree relatives of patients with small intestinal carcinoid tumors have developed these tumors with high incidence. Because of the rareness of this tumor, the absolute risk remains moderate even within families. Gastroenterologists could inform patients with small intestinal carcinoids about the familial risk and encourage counseling for their first-degree relatives. Studies are needed to identify genetic factors that affect susceptibility to SIC.

Risk of second primary cancer after treatment for esophageal cancer: a pooled analysis of nine cancer registries

The introduction of new treatments for esophageal cancer including surgery, chemotherapy, radiotherapy, or a combination of these modalities has not only improved patient survival, but may also increase the risk of the second primary cancers. The available evidence is conflicting with most risk estimates based on sparse numbers. Here we estimated standardized incidence ratios (SIRs) of second cancer among 24,557 esophageal cancer survivors (at least 2 months) in the Surveillance, Epidemiology, and End Results (SEER) Program between 1973 and 2007, who had been followed up for median 6.5 years (range 2 months-29.3 years). Second cancer risk was statistically significantly elevated (SIR = 1.34, 95% confidence interval [CI]= 1.25-1.42) among the survivors compared with the general population; the SIRs for cancers of oral and pharynx, stomach, small intestine, larynx, lung and bronchus, thyroid and prostate cancer were 8.64 (95% CI = 7.36-10.07), 2.87 (95% CI = 2.10-3.82), 3.80 (95% CI = 1.82-7.00), 3.19 (95% CI = 2.12-4.61), 1.68 (95% CI = 1.46-1.93), 2.50 (95% CI = 1.25-4.47), and 0.77 (95% CI = 0.65-0.90), respectively. Radiotherapy raised cancer risk of larynx (SIR = 3.98, 95% CI = 2.43-6.14) and thyroid (SIR = 3.57, 95% CI = 1.54-7.03) among all esophageal cancer survivors. For patients who had 5-9 years of follow up after radiotherapy, the SIR for lung cancer was 3.46 (95% CI = 2.41-4.82). Patients with esophageal cancer are at increased risks of second cancers of oral and pharynx, larynx, lung, and thyroid, while at a decreased risk for prostate cancer. These findings indicate that radiotherapy for esophageal cancer patients may increase risk of developing second cancers of larynx, lung, and thyroid. Thus, randomized clinical trials to address the association of radiotherapy and the risk of secondary cancer are warranted.

Clinical presentations of thyroid cancer patients with multiple primary cancers

BACKGROUND

In thyroid cancer patients with multiple primary cancers, primary cancers tend to be more aggressive.

AIMS

We analyzed multiple primary cancers in thyroid cancer patients and determined the differences between the incidence and the characteristics of primary cancers.

MATERIALS AND METHODS

A total of 3070 patients with thyroid cancer underwent a thyroidectomy and follow-up examination at a single medical center. The times of diagnosis of the primary cancers were categorized as antecedent, synchronous, or subsequent to the diagnosis of thyroid cancer.

RESULTS

After a mean follow-up period of 8.8 ± 0.5 yr, the presence of multiple primary cancers was histopathologically confirmed in 163 patients (5.3%). Patients with multiple primary cancers had a lower female-to-male ratio, an older mean age, advanced tumor-node-metastasis (TNM) stage, higher total mortality, and higher therapeutic radioactive iodide (131I) doses than patients without multiple primary cancers. Hematological malignancy and renal cell carcinoma, neither of which are among the 10 most common cancers observed in the general population of Taiwan, were the most common multiple cancers among women and men with thyroid cancer. Patient age, thyroid cancer tumor size, and thyroid cancer mortality in the antecedent, synchronous, and subsequent groups were not significantly different.

CONCLUSIONS

Patients with multiple primary cancers in advanced stages had shorter disease-free survival period after treatment. Thyroid cancer patients with multiple primary cancers should be closely followed up for the occurrence of other secondary cancers in order to improve total mortality.

Incidence of second primary malignancies during a long-term surveillance of patients with differentiated thyroid carcinoma in relation to radioiodine treatment

PURPOSE

Controversies remain over the actual risk of developing a second primary malignancy (SPM) as a consequence of I-131 treatment in patients with differentiated thyroid carcinoma (DTC). The objective of this study was to evaluate the adjusted rate and risk estimate of SPM in radioiodine-treated patients after controlling for confounding factors.

MATERIALS AND METHODS

A retrospective cohort study was conducted on 973 cases randomly selected from a population of 9550 radioiodine-treated DTC patients. The cases with prior or coincident nonthyroid malignancies and those with SPM during the first 3 years of the initial I-131 treatment were not included. Age-standardized rate of SPM and its 95% confidence interval (CI) during a median of 6 (3-26) years follow-up in DTC patients was compared with that of the general population. A logistic multivariable analysis was also conducted to identify the potential covariate factors that might influence the risk of SPM.

RESULTS

Eleven patients from 7370 person-years at risk developed an SPM. The standardized rate ratio of nonthyroid malignancy was 0.81 (95% CI, 0.57-1.04) for the studied patients relative to the general population. The cumulative dose of I-131 more than 40 GBq (1.08 Ci) was the sole factor associated with increased odds of SPM, after adjusting for age, follow-up duration, histology of DTC, presence of metastasis, and history of external radiotherapy (odds ratio, 113; 95% CI, 8.6-1495.6; P < 0.0001).

CONCLUSIONS

The overall rate of SPMs was not significantly increased after a minimum interval of 3 years from the first I-131 treatment; however, the chance of this event may be radically increased in patients who had received a cumulative activity of I-131 exceeding 40 GBq (1.08 Ci).

Craniopharyngioma in a patient with acromegaly due to a pituitary macroadenoma

We present the first reported case of a craniopharyngioma as a second primary tumor in a patient with acromegaly due to a growth hormone (GH)-secreting pituitary adenoma. The patient was lost for follow-up for 18 years after trans-sphenoidal pituitary surgery for a GH-secreting pituitary adenoma. She presented with headaches and decreased visual acuity, and showed unsuppressed GH in an oral glucose load test with high IGF-1 levels. Brain MRI showed a suprasellar cystic mass and the patient underwent surgery for cyst drainage resulting in postoperative improvement in her vision. Biopsy of the mass confirmed the diagnosis of a craniopharyngioma. We stress the need for close follow-up of patients with acromegaly with adequate control of GH and IGF-1 levels.

Risk factors for pituitary tumors: a case-control study

Pituitary gland tumors are usually benign but are associated with substantial morbidity. Their etiology is largely unknown. We conducted a population-based case-control study of potential risk factors for pituitary tumors in Southeast England. Information on medical and reproductive history, female sex hormones, and cigarette smoking was collected by personal interview from 299 cases and 630 controls aged 18 to 59 years. Tumor risk was reduced in subjects reporting a past diagnosis of hay fever [odds ratio (OR), 0.7; 95% confidence interval (CI), 0.5-1.0] but not asthma or eczema. Risk was raised in women who were postmenopausal 1 year before diagnosis (OR, 3.2; 95% CI, 1.6-6.2), especially if menopause was surgically induced (OR, 6.7; 95% CI, 2.2-19.9) or occurred under age 40 years (OR, 7.5; 95% CI, 2.6-21.4). This effect remained when evaluating menopausal status 10 years before diagnosis. There was no association with parity overall, but risk was increased for first childbirth under age 20 years compared with nulliparity (OR, 3.4; 95% CI, 1.4-8.4). No significant association was observed with ever use of oral contraceptives or hormone replacement therapy, nor with cigarette smoking, past head injury, past diagnosis with epilepsy, or birth characteristics, except for an inverse association of risk with maternal age. This study suggests a raised risk of pituitary tumors in relation to surgically induced menopause, early postmenopausal age, and young age at childbirth, and possibly a reduced risk with hay fever and increasing maternal age. Reasons for these associations need further investigation, but some associations might be due to hormonal effects of an undiagnosed pituitary tumor.

Acromegaly: re-thinking the cancer risk

Acromegaly is characterized by sustained elevation of circulating growth hormone (GH) and insulin-like growth factor I (IGF-I), and is clearly associated with increased morbidity and overall mortality mainly due to cardiovascular, metabolic, and respiratory diseases. Although cancer-related mortality varies widely amongst retroperspective studies, it appears to be consistently elevated mainly in patients with uncontrolled disease. We review individual tumor types including neoplasms of the colon, breast, prostate, and thyroid where in vitro, animal studies, and studies in non-acromegalic cancer patients have established a role for the GH/IGF-I axis in tumor progression and possibly initiation. We highlight deficiencies in data in acromegalic patients where the evidence is less convincing. Instead, we explore the hypothesis that acromegaly, independent of hormone secretion, is a disease that heralds genetic and/or epigenetic alterations predisposing to cancer risk elsewhere.

The risk of second primary malignancies up to three decades after the treatment of differentiated thyroid cancer

BACKGROUND

The 10-yr survival rate of patients with differentiated thyroid cancer exceeds 90%. These patients may be at elevated risk for secondary cancers.

METHODS

The risk of nonthyroid second primary malignancies after differentiated thyroid cancer was determined in 30,278 patients diagnosed between 1973 and 2002 from centers participating in the National Cancer Institute's Surveillance, Epidemiology, and End Results program. Median follow-up was 103 months (range, 2-359 months). Risk was further assessed for the addition of radioisotope therapy, gender, latency to development of secondary cancer, and age at thyroid cancer diagnosis.

RESULTS

There were 2158 patients who developed a total of 2338 nonthyroid second primary malignancies, significantly more than that expected in the general population [observed/expected (O/E) = 1.09; 95% confidence interval (CI), 1.05-1.14; P < 0.05; absolute excess risk per 10,000 person-years (AER) = 6.39]. A significantly greater risk of second primary malignancies over that expected in the general population was for patients treated with radioisotopes (O/E = 1.20; 95% CI, 1.07-1.33; AER = 11.8) as well as for unirradiated patients (O/E = 1.05; 95% CI, 1.00-1.10; AER = 3.53). However, the increased risk was greater for the irradiated vs. the unirradiated cohort (relative risk = 1.16; 95% CI, 1.05-1.27; P < 0.05). Gender did not affect risk. The greatest risk of second primary cancers occurred within 5 yr of diagnosis and was elevated for younger patients.

CONCLUSIONS

The overall risk of second primary malignancies is increased for thyroid cancer survivors and varies by radioisotope therapy, latency, and age at diagnosis.

Risk of second primary malignancies and causes of death in patients with adenocarcinoma and carcinoid of the small intestine

We studied risk of second malignancies and causes of death in 1829 cases of adenocarcinoma and 3055 cases of carcinoid tumours in the small bowel reported to the Swedish Cancer Registry from 1960 through to 2000. Data on causes of death were analysed as from 1966 whereas data on second tumours was available during the whole registry-period. Follow-up was available until 2001. Standard mortality ratio (SMR) and standard incidence ratio (SIR) were calculated. Female patients with adenocarcinoma had increased risk of acquiring cancer in the female genital organs (SIR 3.2; 95% confidence intervals (CI) 1.9-5.0) and breasts (SIR 2.7; 95% CI 1.1-5.4). Both sexes combined had increased risk of second tumours in the gastrointestinal tract (SIR 1.5; 95% CI 1.1-2.1) and skin (SIR 4.6; 95% CI 1.2-12). Men with carcinoid tumour had increased risk of prostate cancer (SIR 2.8; 95% CI 1.6-4.6). Increased risk was seen for both sexes with carcinoid for malignant melanoma (SIR 6.3; 95% CI 2.7-12), malignant skin tumours (SIR 3.6; 95% CI 1.7-6.7) and malignancies of endocrine organs (SIR 2.3 95% CI 1.3-3.8). Patients with adenocarcinoma had increased risk of dying from malignant diseases other than the primary cancer (SMR 9.5; 95% CI 8.6-10) and gastrointestinal disease (SMR 2.6 95% CI 1.6-4.2). The cohort with carcinoid had higher than expected risk of dying from malignant disease (SMR 4.3; 95% CI 4.0-4.6), gastrointestinal disease (SMR 2.8; 95% CI 2.1-3.6) and cardiovascular disease (SMR 1.1; 95% CI 1.0-1.3). The increased risk of second malignant tumours is an indication of common aetiology, or possibly, a general vulnerability to malignant disease for these patients. A detailed analysis of causes of death in a population-based cohort of small intestinal malignancies has not been presented before in the literature.

Second primary malignancy risk in thyroid cancer survivors: a systematic review and meta-analysis

OBJECTIVE

To determine the risk of second primary malignancies (SPMs) in thyroid cancer survivors.

DESIGN

We performed a systematic review and meta-analysis examining the standardized incidence ratios (SIRs) of SPMs in thyroid cancer survivors (compared to individuals without thyroid cancer). Two independent reviewers screened citations and reviewed all full-text papers deemed potentially relevant. Final consensus was reached on inclusion of papers in the review. Data were pooled using fixed effects models.

MAIN OUTCOMES

Thirteen full-text papers were included. The incidence of SPMs in thyroid cancer survivors was increased with an SIR of 1.20 (95% confidence interval 1.17, 1.24) (based on pooled data from six studies of 70,844 thyroid cancer survivors). The SIR of the following SPMs was significantly increased: salivary gland, stomach, colon/colorectal, breast, prostate, kidney, brain/central nervous system, soft tissue sarcoma, non-Hodgkin's lymphoma, multiple myeloma, leukemia, bone/joints, and adrenal. A significantly reduced risk of lung and cervical cancers was observed.

CONCLUSIONS

Thyroid cancer survivors are at increased risk of SPMs, which may be related to disease-specific treatments or genetic predisposition.

Second primary cancers in thyroid cancer patients: a multinational record linkage study

CONTEXT

Increasing incidence and improved prognosis of thyroid cancer have led to concern about the development of second primary cancers, especially after radioiodine treatment. Thyroid cancer can also arise as a second primary neoplasm after other cancers.

OBJECTIVE

The objective of the study was to assess the risk of second primary cancer after thyroid cancer and vice versa.

DESIGN

This was a multinational record linkage study.

SETTING

The study was conducted at 13 population-based cancer registries in Europe, Canada, Australia, and Singapore.

PATIENTS OR OTHER PARTICIPANTS

A cohort of 39,002 people (356,035 person-yr of follow-up) with primary thyroid cancer were followed up for SPN for up to 25 yr, and 1,990 cases of thyroid cancer were diagnosed after another primary cancer.

MAIN OUTCOME MEASURES

To assess any possible excess of second primary neoplasms after thyroid cancer, the observed numbers of neoplasms were compared with expected numbers derived from age-, sex-, and calendar period-specific cancer incidence rates from each of the cancer registries, yielding standardized incidence ratios (SIRs). The SIR of second primary thyroid cancer after various types of cancer was also calculated.

RESULTS

During the observation period, there were 2821 second primary cancers (all sites combined) after initial diagnosis of thyroid cancer, SIR of 1.31 (95% confidence interval 1.26-1.36) with significantly elevated risks for many specific cancers. Significantly elevated risks of second primary thyroid cancer were also seen after many types of cancer.

CONCLUSION

Pooled data from 13 cancer registries show a 30% increased risk of second primary cancer after thyroid cancer and increased risks of thyroid cancer after various primary cancers. Although bias (detection, surveillance, misclassification) and chance may contribute to some of these observations, it seems likely that shared risk factors and treatment effects are implicated in many. When following up patients who have been treated for primary thyroid cancer, clinicians should maintain a high index of suspicion for second primary cancers.

Associations between small intestine cancer and other primary cancers: an international population-based study

Cancer of the small intestine is a rare neoplasm, and its etiology remains poorly understood. Analysis of other primary cancers in individuals with small intestine cancer may help elucidate the causes of this neoplasm and the underlying mechanisms. We included 10,946 cases of first primary small intestine cancer from 13 cancer registries in a pooled analysis. The observed numbers of 44 types of second primary cancer were compared to the expected numbers derived from the age-, gender- and calendar period-specific cancer incidence rates in each registry. We also calculated the standardized incidence ratios (SIR) for small intestine cancer as a second primary after other cancers. There was a 68% overall increase in the risk of a new primary cancer after small intestine carcinoma (SIR = 1.68, 95% confidence interval [CI] = 1.47-1.71), that remained constant over time. The overall SIR was 1.18 (95% CI = 1.05-1.32) after carcinoid, 1.29 (1.01-1.63) after sarcoma, and 1.27 (0.78-1.94) after lymphoma. Significant (p < 0.05) increases were observed for cancers of the oropharynx, colon, rectum, ampulla of Vater, pancreas, corpus uteri, ovary, prostate, kidney, thyroid gland, skin and soft tissue sarcomas. Small intestine cancer as a second primary was increased significantly after all these cancers, except after oropharyngeal and kidney cancers. Although some of the excess may be attributable to overdiagnosis, it is plausible that most additional cases of second primary cancers were clinically relevant and were due to common genetic (e.g., defects in mismatch or other DNA repair pathways) and environmental (e.g., dietary) factors.

Thyroid cancer and multiple primary tumors in the SEER cancer registries

Thyroid cancer incidence rates have increased steadily in the United States and elsewhere. Radiation exposure at a young age is a strong risk factor, but otherwise the etiology is unclear. To explore etiologic clues, we studied the risk of thyroid cancer after an earlier primary cancer, as well as the risk of developing multiple primaries after an earlier thyroid cancer in the U.S. Surveillance, Epidemiology and End-Results (SEER) cancer registries program (1973-2000). In 2,036,597 patients diagnosed with any invasive cancer who survived for a minimum of 2 months, we observed a 42% increased risk compared to the general population for second thyroid cancer based on 1,366 cases (95% confidence interval (CI) = 35-50%; excess absolute risk (EAR) = 0.38/10,000 person-years (PY)). Elevated risks were observed after most cancer sites studied. The most pronounced excess (observed/expected (O/E) = 2.86) was seen for second thyroid cancers detected in the year after diagnosis of the first cancer. Among 29,456 2-month thyroid cancer survivors, 2,214 second cancers occurred (O/E = 1.11, 95% CI = 1.06-1.15; EAR = 7.64/10,000 PY). Again, the highest risk was seen in the first year (O/E = 1.26). Patients <40 years of age at diagnosis of thyroid cancer had a 39% increased risk of a second cancer, whereas for older patients the risk was elevated 6%. We observed consistently increased risks for cancers of the breast, prostate, and kidney, and a likely radiation treatment-related excess of leukemia. Based on small numbers of cases, cancers of the salivary glands, trachea, scrotum, adrenal glands, and brain and central nervous system (CNS) also occurred in excess. A decreased risk was observed for smoking-related malignancies. Thyroid cancer is associated with primary cancers of many different organs. Although enhanced medical surveillance likely plays a role, 2-way, positive associations between thyroid cancer and cancers of the breast, prostate, kidney, salivary glands, brain and CNS, scrotum, and leukemia suggest etiologic similarities and possible treatment effects.

Meningiomas may be a component tumor of multiple endocrine neoplasia type 1

PURPOSE

Recently, an increased incidence of some nonendocrine tumors are reported in patients with multiple endocrine neoplasia type 1 (MEN 1). There are rare reports of meningiomas and other central nervous system tumors in these patients, but it is unknown if they are more frequent or if allelic loss of the MEN1 gene is important in their pathogenesis. The aim of this study was to address these two latter questions.

EXPERIMENTAL DESIGN

Results from a prospective study of 74 MEN 1 patients with suspected/proven pancreatic endocrine tumors (PETs) were analyzed, as well as molecular studies performed on a resected meningioma. All patients had serial brain imaging studies (computed tomography, magnetic resonance imaging, and octreoscanning since 1994) and yearly studies evaluating MEN 1 involvement with a mean follow-up of 7.2 years. Results were compared with 185 patients with sporadic Zollinger-Ellison syndrome.

RESULTS

Six patients (8%) had meningiomas. Meningiomas were single and found late in the MEN 1 course (mean age = 51 years). Magnetic resonance imaging/computed tomography were more sensitive than octreoscanning. Their diagnosis averaged 18 years after the onset of hyperparathyroidism, 10-15 years after pituitary disease or PETs. Meningiomas were 11 times more frequent in patients with PETs with MEN 1 than without MEN 1 (P = 0.017). No clinical, laboratory, or MEN 1 feature distinguished patients with meningiomas. Meningiomas were asymptomatic and 60% showed no growth. A resected meningioma showed loss of heterozygosity at 11q13 and 1p, including at p73 and ARHI/NOEY2 locus, but not at the neurofibromatosis 2 gene locus.

CONCLUSIONS

These results show meningiomas are not an infrequent occurrence in MEN 1, and loss of the function of the MEN1 gene product plays a role in their pathogenesis in these patients.

Genetic epidemiology of cancer: From families to heritable genes

A reliable determination of familial risks for cancer is important for clinical counseling, prevention and understanding cancer etiology. Family-based gene identification efforts may be targeted if the risks are well characterized and the mode of inheritance is identified. Medically verified data on familial risks have not been available for all types of cancer but they have become available through the use of the nationwide Swedish Family-Cancer Database, which includes all Swedes born in 1932 and later with their parents, totaling over 10 million individuals. Over 150 publications have emanated from this source. The familial risks of cancer have been characterized for all main cancers and the contribution of environmental and heritable effects to the familial aggregation has been assessed. Furthermore, the mode of inheritance has been deduced by comparing risks from parental and sibling probands. Examples are shown on familial clustering of cancers, for which heritable susceptibility genes are yet unknown, such as squamous cell carcinoma of the skin, intestinal carcinoids, thyroid papillary tumors, brain astrocytomas and pituitary adenomas. Some common cancers, such as lung and kidney cancers, appear to show an early-onset recessive component because familial risks among siblings are much higher than those in families where parents are probands. Many of the cancer sites showing high familial risks lack guidelines for clinical counseling or action level. In conclusion, we recommend that any future gene identification efforts, either using linkage or association designs, devise their strategies based on data from family studies. Clinical genetic counseling would benefit from reviewing established familial risks on all main types of cancer.

Multiple primary tumors involving cancer of the brain and central nervous system as the first or subsequent cancer

BACKGROUND

This study was undertaken to determine whether cancer of the brain and central nervous system (CNS) occurs together with other types of cancer more often or less often than would be expected due to chance.

METHODS

The study was based on data collected by the Surveillance, Epidemiology, and End Results (SEER) Program for cancers diagnosed in the U.S. between 1973 and 1998. The standardized incidence ratio (SIR) for new malignancies was estimated as the number of patients diagnosed with a particular type of cancer (observed), divided by the number of diagnoses expected based on person-years of follow-up and incidence rates for SEER cancer registries.

RESULTS

Among patients who were diagnosed first with cancer of the brain or CNS, statistically significant excesses were observed for cancers of bone (SIR = 14.4), soft tissue (SIR = 4.6), brain and CNS (SIR = 5.9), salivary gland (SIR = 5.1), and thyroid gland (SIR = 2.7) in addition to acute myelocytic leukemia (SIR = 4.1) and melanoma of the skin (SIR = 1.7). Excess risk of new malignancies was markedly greater after first cancers of the brain or CNS diagnosed in childhood compared with similar diagnoses in adulthood. In reverse associations, significant excesses of cancer of the brain and CNS were observed only after diagnoses of acute lymphocytic leukemia (SIR = 7.4) and cancer of the testis (SIR = 1.8) or the thyroid gland (SIR = 1.7).

CONCLUSIONS

Cancer treatment appears to have been the major factor underlying most of the positive associations between brain cancer and primary cancers of other types, with a probable lesser contribution from shared genetic susceptibility. Results provide little or no evidence that brain cancer shares important etiologic factors with the common cancers of adulthood.

Gender effects in familial cancer

Very limited data are available on sex ratios in familial cancer. Such data would be valuable in the assessment of sex chromosome effects and of interactions between background and familial rates. We used the nationwide Swedish Family-Cancer Database on 10.2 million individuals and over 1 million neoplasms to analyze familial risks for male and female offspring by paternal and maternal concordant cancer. Sex ratios for familial cancer were derived for cancer at 15 sites shared by men and women. At 14 sites the sex ratio (male/female) for familial relative risk ranged between 0.78 and 1.41, with no evidence of sex preference, suggesting that sex chromosomes do not contribute to a noticeable extent to familial risks. Furthermore, in cancers where the background incidence varied extensively by sex, such as bladder cancer (sex ratio 2.82) and nonthyroid endocrine tumors (0.65), the familial effect was proportionate to the background incidence and the familial sex ratio was close to unity. In thyroid cancer, the familial sex ratio was 2.48 (1.54-3.98) and the background incidence ratio was 0.31. This was the first evidence of an inverse sex ratio in primary cancer, i.e., higher familial risk in the gender of low background risk. The high familial ratio, 2.85 (95% CI: 1.35-6.03), was due to thyroid adenocarcinoma, encompassing both papillary and follicular types.