Number Of Second Primary Cancers Research Articles

Is the linear no-threshold (LNT) model relevant for radiotherapy?

Initially considered as a kind of radiobiological law, the linear no-threshold (LNT) model, which by definition supports the absence of any threshold for cancer risk induction after irradiation, is nowadays more reasonably described as a pragmatic and prudent approach by the International Organizations. However, it remains today a dogma in radiological protection. Actually, this model had been essentially developed for the radiological protection of a general population against low, and sometimes very low, doses of irradiation. Radiation oncologists are dealing with a totally different situation since they deliver, on purpose, high doses of radiations in more or less limited volumes of the body of cancer patients, patients for whom no other alternatives do exist to get rid of their malignant tumors. Simultaneously, the radiation oncologists inevitably give low and even very low doses at distance from the so-called target volumes. In such a specific situation, what is the carcinogenicity of these low doses and the relevance of the LNT model in radiotherapy? Thus, this paper addresses three critical questions: 1) what is the risk acceptability of the radiation doses delivered by radiotherapy of malignant tumors? 2) what is the real carcinogenic risk of (very) low doses delivered at distance from the target volume? 3) are the clinical radiotherapy data, i.e., the number of second primary cancers, accumulated since more than a century, consistent with the LNT model? In conclusion, the LNT model appears to be poorly adapted to the high doses locally delivered to cancer patients and dramatically overestimates, in most cases, the risk of secondary radio-induced cancers. In fine, the real risk of the LNT model in radiotherapy would be to promote radiophobia in cancer patients and to see some of them turning away from a life-saving treatment.

Predicting the Risk Factors of Second Primary Cancer in Patients with Hepatocellular Carcinoma.

Screening for cancer and improved treatments have not only improved treatment outcomes and patient survival but have also led to an increase in the number of second primary cancers (SPCs). Hepatocellular carcinoma has been a common occurrence in Taiwan over the past decade. The mortality rate is second only to malignant tumors of lung cancer, and it also represents the fourth highest cancer medical expenditure. This study aimed to use machine learning to identify the risk factors for Hepatocellular carcinoma survivors. Of 378,445 datasets, including 15,251 from patients with SPCs, were collected; 18 predictive variables were considered risk factors for SPCs based on the physician panel discussion. The machine learning techniques employed included support vector machine, C5 decision tree, and random forest. SMOTE (Synthetic Minority Oversampling Technique) sampling method was used to resolve the imbalance problem. The results showed that the top 5 risk factors for SPCs were tumor size, clinical stage, surgery, total bilirubin, and BCLC Stage. The support vector machine method had the highest predicted accuracy (0.7673). The risk factors extracted from the classification models and association rules will be used to provide valuable information for HCC therapy.

Second malignancies following conventional or combined ²⁵²Cf neutron brachytherapy with external beam radiotherapy for breast cancer.

We retrospectively evaluated the risk of second malignancies among 832 patients with inner or central breast cancer treated with conventional external beam schedule (CRT group), or neutron brachytherapy using Californium-252 (252Cf) sources and hypofractionated external beam radiotherapy (HRTC group), between 1987 and 1996 at the Institute of Oncology, Vilnius University. Patients were observed until the occurrences of death or development of a second malignancy, or until 31 December 2009, whichever was earlier. Median follow-up time was 10.4 years (range, 1.2–24.1 years). Risk of second primary cancers was quantified using standardized incidence ratios (SIRs). Cox proportional hazards regression models were used to estimate hazard ratios (HRs). There was a significant increase in the risk of second primary cancers compared with the general population (SIR 1.3, 95% CI 1.1–1.5). The observed number of second primary cancers was also higher than expected for breast (SIR 1.8, 95% CI 1.3–2.4) and lung cancer (SIR 3.8, 95% CI 2.0–6.7). For second breast cancer, no raised relative risk was observed during the period ≥10 or more years after radiotherapy. Compared with the CRT group, HRTC patients had a not statistically significant higher risk of breast cancer. Increased relative risks were observed specifically for age at initial diagnosis of <50 years (HR 2.9, 95% CI 1.6–5.2) and for obesity (HR 2.8, 95% CI 1.1–7.2).

Analysis of second primary cancers in gastroinstestinal stromal tumor patients using SEER database.

327 Background: Development of second primary cancers among gastrointestinal stromal tumor (GIST) patients is not very well studied. This study was conducted to evaluate second primary malignancies in GIST patients using U.S. Surveillance, Epidemiology, and End Results (SEER) cancer registry database. Methods: We analyzed the Surveillance, Epidemiology, and End Results (SEER Stat) database: Incidence - SEER 13 Regs Research Data, Nov 2011 Sub, Vintage 2009 Pops (1992-2009) using MP-SIR session. We analysed secondary cancer rate among adult GIST patients during the period 1992-2009. We also compared the risk of secondary malignancies in pre- (1992-2001) to post-imatinib (2002-2009) eras. We used SEER MP-SIR session and Graph pad scientific software to calculate p value. Results: There were 2,436 (693 in pre-imatinib era and 1,743 in post-imatinib era) GIST patients reported during 1992-2009 period in SEER database. Among them, 163 GIST patients developed second primary malignancy, which is significantly higher than expected in general population, with observed/expected (O/E) ratio: 1.31, p value = &lt;0.05, (95% CI: 1.11-1.52) and excess risk of 39.76 per 10,000 population. The total number of second primary cancers in GIST in pre- and post-imatinib eras were 69 and 94, p value = &lt;0.0001 with observed/expected (O/E) ratio of 29.18 and 48.22 respectively. The total number of second primary solid tumors in pre- and post-imatinib era was: 59 and 84, p value=0.0008 and O/E ratio: 20.18 vs 43.32 respectively. Conclusions: This study showed overall increased risk of second primary malignancies among GIST patients as compared to general population. There was significantly increased risk of second primary malignancies, especially solid tumors in post-imatinib era. [Table: see text]

The relative risk of second primary cancers in Queensland, Australia: a retrospective cohort study

BackgroundCancer survivors face an increased likelihood of being subsequently diagnosed with another cancer. The aim of this study was to quantify the relative risk of survivors developing a second primary cancer in Queensland, Australia.MethodsStandardised incidence rates stratified by type of first primary cancer, type of second primary cancer, sex, age at first diagnosis, period of first diagnosis and follow-up interval were calculated for residents of Queensland, Australia, who were diagnosed with a first primary invasive cancer between 1982 and 2001 and survived for a minimum of 2 months.ResultsA total of 23,580 second invasive primary cancers were observed over 1,370,247 years of follow-up among 204,962 cancer patients. Both males (SIR = 1.22; 95% CI = 1.20-1.24) and females (SIR = 1.36; 95% CI = 1.33-1.39) within the study cohort were found to have a significant excess risk of developing a second cancer relative to the incidence of cancer in the general population. The observed number of second primary cancers was also higher than expected within each age group, across all time periods and during each follow-up interval.ConclusionsThe excess risk of developing a second malignancy among cancer survivors can likely be attributed to factors including similar aetiologies, genetics and the effects of treatment, underlining the need for ongoing monitoring of cancer patients to detect subsequent tumours at an early stage. Education campaigns developed specifically for survivors may be required to lessen the prevalence of known cancer risk factors.

Secondary cancers after a lung carcinoid primary: A population-based analysis

Carcinoid tumors of the lung were first described in 1937, yet little is known about their etiology. The aim of the present investigation was to determine if there was excess risk of secondary cancers in a population-based sample after a lung carcinoid tumor diagnosis which may provide insight to the etiology. Subjects were 1882 cases diagnosed with carcinoid tumors of the lung between 1988 and 2000 whose information was obtained from the Surveillance, Epidemiology and End Results (SEER) Program database. Standardized incidence ratios were calculated by dividing the observed number of second primary cancers by the expected number of cancers. Excess risk of breast cancer was seen following diagnosis of a carcinoid tumor (SIR=1.80 95% CI 1.22-2.55). When stratified by time after diagnosis, excess risk of breast cancers in women was seen in the first 5 years after carcinoid diagnosis (SIR=1.68 95% CI 1.08-2.50) but fewer than expected breast cancers were diagnosed greater than 5 years after carcinoid diagnosis (SIR=0.29 95% CI 0.09-0.68). Prostate cancers also occurred 2.8 times more often than expected (95% CI 1.66-4.43), with risk being elevated only in the first 5 years post-carcinoid diagnosis. Development of lung carcinoids may be the result of genetic predisposition or environmental exposures, particularly those that are hormonally related. The role of genetics and sex hormones in lung carcinoid development, as well as the identification of other risk factors, should be explored.

Breast carcinoma after cancer at another site

BACKGROUND As the number of cancer survivors increases, so will the number of second primary cancers, including breast carcinoma after cancer at another site. Limited information is available regarding the clinical characteristics of breast carcinoma after a primary at another site. METHODS TUMORS (The Upper Midwest Oncology Registry Services) was used to identify 937 women with breast carcinoma occurring as a second primary after a first primary at a known site other than the breast. They were compared with a sample of 1874 women with first primary breast carcinoma, frequency-matched by age to the second primary group, for method of detection, tumor characteristics, and type of surgery. RESULTS Women with breast carcinoma after cancer at another site tended to have smaller tumors and less extensive disease than women with first primary breast carcinoma and were somewhat more likely than first primary cases to have had their breast carcinoma detected by mammogram or clinical breast exam rather than detecting it themselves. Differences in method of detection accounted for differences in tumor size and extent. Second primary breast carcinoma was less likely to be lobular or mixed ductolobular carcinoma compared with first primary breast carcinoma. Surgical treatment (mastectomy vs. breast-conserving surgery) did not differ for first and second primary breast carcinoma. CONCLUSIONS Clinical characteristics of breast carcinoma after cancer at another site were by and large similar to those of first primary breast carcinoma. The more favorable prognostic characteristics among women with a history of cancer were accounted for by increased medical surveillance. Cancer 2000;89:1999–2005. © 2000 American Cancer Society.

Breast carcinoma after cancer at another site: method of detection, tumor characteristics, and surgical treatment.

As the number of cancer survivors increases, so will the number of second primary cancers, including breast carcinoma after cancer at another site. Limited information is available regarding the clinical characteristics of breast carcinoma after a primary at another site. TUMORS (The Upper Midwest Oncology Registry Services) was used to identify 937 women with breast carcinoma occurring as a second primary after a first primary at a known site other than the breast. They were compared with a sample of 1874 women with first primary breast carcinoma, frequency-matched by age to the second primary group, for method of detection, tumor characteristics, and type of surgery. Women with breast carcinoma after cancer at another site tended to have smaller tumors and less extensive disease than women with first primary breast carcinoma and were somewhat more likely than first primary cases to have had their breast carcinoma detected by mammogram or clinical breast exam rather than detecting it themselves. Differences in method of detection accounted for differences in tumor size and extent. Second primary breast carcinoma was less likely to be lobular or mixed ductolobular carcinoma compared with first primary breast carcinoma. Surgical treatment (mastectomy vs. breast-conserving surgery) did not differ for first and second primary breast carcinoma. Clinical characteristics of breast carcinoma after cancer at another site were by and large similar to those of first primary breast carcinoma. The more favorable prognostic characteristics among women with a history of cancer were accounted for by increased medical surveillance.

Incidence of Second Primary Cancers in Osaka Residents, Japan, with Special Reference to Cumulative and Relative Risks

This study was conducted to examine the incidence rates and cumulative risks of second primary cancers in Osaka and to compare the observed number of second primary cancers with the expected number calculated using cancer incidence rates among Osaka residents. Study subjects were all reported cases aged 0–79 who were first diagnosed as having a first primary cancer between 1966–86. Incidence of second primary cancer among the study subjects was examined through to the end of 1989. The total number of study subjects was 217,307. During the follow‐up period (mean duration: 3.7 years), second primary cancers developed in 5,071 patients (2.3%). Incidence of synchronous (interval <3 months) and metachronous (interval ≥ 3 months) second primary cancers increased in the later years. Incidence rates of second primary cancers were significantly associated with gender (male), age and calendar year at diagnosis of the first cancer. Based on the incidence rates, cumulative risk of developing metachronous second primary cancer was calculated. The ten‐year cumulative risk was estimated as 10% for those who developed their first cancer during their sixties in 1978–83. The observed number of second primary cancers (including synchronous) was compared with the expected number. The ratios of observed‐to‐expected numbers were generally lower than 1.0 among those who developed their first cancer in 1966–77, while these ratios were higher than 1.0 among those who developed their first cancer in 1978–86. The ratios were much higher than 1.0 among those who developed their first cancer in their childhood and youth. Patients who had developed cancer of the colon, larynx, lung, bladder, or breast (female) showed significantly higher risk of developing second primary cancer during the period 1–4 years after diagnosis of the first cancer.

New cancers arising in 1,563 patients with carcinoma of the cervix treated by irradiation

This report is concerned with the incidence of multiple primary cancers developing in 1,563 patients treated for invasive carcinoma of the cervix. They were all treated by radium and/or external irradiation. Follow-up was complete with the exception of 69 patients (4.4 per cent). Total person years of observation was 8,323. Thirty second primaries of different organs and of different cell type were found. Skin cancers and multicentric squamous-celled cancers were excluded as were synchronous cancers. The observed number of second primary cancers (30) was compared to the expected number (29.2) derived from the Connecticut Cancer Registry, with the use of age- and site-specific incidence rates. No increased incidence of second cancer was found among the patients studied.