Oncological care was largely derailed due to the reprioritisation of health care services to handle the initial surge of COVID-19 patients adequately. Cancer screening programmes were no exception in ...this reprioritisation. They were temporarily halted in the Netherlands (1) to alleviate the pressure on health care services overwhelmed by the upsurge of COVID-19 patients, (2) to reallocate staff and personal protective equipment to support critical COVID-19 care, and (3) to mitigate the spread of COVID-19. Utilising data from the Netherlands Cancer Registry on provisional cancer diagnoses between 6 January 2020 and 4 October 2020, we assessed the impact of the temporary halt of national population screening programmes on the diagnosis of breast and colorectal cancer in the Netherlands. A dynamic harmonic regression model with ARIMA error components was applied to assess the observed versus expected number of cancer diagnoses per calendar week. Fewer diagnoses of breast and colorectal cancer were objectified amid the early stages of the initial COVID-19 outbreak in the Netherlands. This effect was most pronounced among the age groups eligible for cancer screening programmes, especially in breast cancer (age group 50-74 years). Encouragingly enough, the observed number of diagnoses ultimately reached and virtually remained at the level of the expected values. This finding, which emerged earlier in age groups not invited for cancer screening programmes, comes on account of the decreased demand for critical COVID-19 care since early April 2020, which, in turn, paved the way forward to resume screening programmes and a broad range of non-critical health care services, albeit with limited operating and workforce capacity. Collectively, transient changes in health-seeking behaviour, referral practices, and cancer screening programmes amid the early stages of the initial COVID-19 epidemic in the Netherlands conjointly acted as an accelerant for fewer breast and colorectal cancer diagnoses in age groups eligible for cancer screening programmes. Forthcoming research is warranted to assess whether the decreased diagnostic scrutiny of cancer during the COVID-19 pandemic resulted in stage migration and altered clinical management, as well as poorer outcomes.
We aimed to determine the prognosis of patients with breast cancer diagnosed during pregnancy (BCP).
In this cohort study, a multicentric registry of patients with BCP (from Cancer in Pregnancy, ...Leuven, Belgium, and GBG 29/BIG 02-03) compiled pro- and retrospectively between 2003 and 2011 was compared with patients who did not have associated pregnancies, using an age limit of 45 years. Patients with a diagnosis postpartum were excluded. The main analysis was performed using Cox proportional hazards regression of disease-free survival (DFS) and overall survival (OS) on exposure (pregnant or not), adjusting for age, stage, grade, hormone receptor status, human epidermal growth factor 2 status, histology, type of chemotherapy, use of trastuzumab, radiotherapy, and hormone therapy.
The registry contained 447 women with BCP, mainly originating from Germany and Belgium, of whom 311 (69.6%) were eligible for analysis. The nonpregnant group consisted of 865 women. Median age was 33 years for the pregnant and 41 years for the nonpregnant patients. Median follow-up was 61 months. The hazard ratio of pregnancy was 1.34 (95% CI, 0.93 to 1.91; P = .14) for DFS and 1.19 (95% CI, 0.73 to 1.93; P = .51) for OS. Cox regression estimated that the 5-year DFS rate for pregnant patients would have increased from 65% to 71% if these patients had not been pregnant. Likewise, the 5-year OS rate would have increased from 78% to 81%.
The results show similar OS for patients diagnosed with BCP compared with nonpregnant patients. This information is important when patients are counseled and supports the option to start treatment with continuation of pregnancy.
When breast cancer patients develop distant metastases, the choice of systemic treatment is usually based on tissue characteristics of the primary tumor as determined by immunohistochemistry (IHC) ...and/or molecular analysis. Several previous studies have shown that the immunophenotype of distant breast cancer metastases may be different from that of the primary tumor ("receptor conversion"), leading to inappropriate choice of systemic treatment. The studies published so far are however small and/or methodologically suboptimal. Therefore, definite conclusions that may change clinical practice could not yet be drawn. We therefore aimed to study receptor conversion for estrogen receptor alpha (ERα), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) in a large group of distant (non-bone) breast cancer metastases by re-staining all primary tumors and metastases with current optimal immunohistochemical and in situ hybridization methods on full sections.
233 distant breast cancer metastases from different sites (76 skin, 63 liver, 43 lung, 44 brain and 7 gastro-intestinal) were IHC stained for ERα, PR and HER2, and expression was compared to that of the primary tumor. HER2 in situ hybridization (ISH) was done in cases of IHC conversion or when primary tumors or metastases showed an IHC 2+ result.
Using a 10% threshold, receptor conversion by IHC for ERα, PR occurred in 10.3%, 30.0% of patients, respectively. In 10.7% of patients, conversion from "ER+ or PR+" to ER-/PR- and in 3.4% from ER-/PR- to "ER+ or PR+" was found. Using a 1% threshold, ERα and PR conversion rates were 15.1% and 32.6%. In 12.4% of patients conversion from "ER+ or PR+" to ER-/PR-, and 8.2% from ER-/PR- to "ER+ or PR+" occurred. HER2 conversion occurred in 5.2%. Of the 12 cases that showed HER2 conversion by IHC, 5 showed also conversion by ISH. One further case showed conversion by ISH, but not by IHC. Conversion was mainly from positive in the primary tumor to negative in the metastases for ERα and PR, while HER2 conversion occurred equally both ways. PR conversion occurred significantly more often in liver, brain and gastro-intestinal metastases.
Receptor conversion by immunohistochemistry in (non-bone) distant breast cancer metastases does occur, is relatively uncommon for ERα and HER2, and more frequent for PR, especially in brain, liver and gastro-intestinal metastases.
Background
This study aimed to validate the DCIS-upstage model, a previously developed model to predict the risk of upstaging to invasive breast cancer in patients with biopsy-proven ductal carcinoma ...in situ (DCIS) in a more recent cohort and to assess the model’s clinical utility.
Methods
The model was validated in a registry cohort (
n
= 2269) and in an institution cohort (
n
= 302). A calibration plot was made, followed by a decision curve analysis (DCA). The model’s area under the curve (AUC) was compared with the AUC of another published model and with the AUCs of new models using the risk factors of the DCIS-upstage model and additional risk factors.
Results
The DCIS-upstage model had an AUC of 0.67 at development; in the validation, the AUC was 0.65 in the registry cohort and 0.73 in the institution cohort. The DCA showed that the model has clinical utility. The other published model had an AUC of 0.66 in the institution cohort. Adding risk factors to the DCIS-upstage model slightly increased the AUC.
Conclusions
The DCIS-upstage prediction model is valid in other cohorts. The model has clinical utility and may be used to select patients with biopsy-proven DCIS for sentinel lymph node biopsy.
There is a large variation between Dutch hospitals in the use of Sentinel Lymph Node Biopsy (SLNB) in patients with a biopsy diagnosis of Ductal Carcinoma in Situ. The aim of our study was to ...investigate whether this variation might be explained by preferences of surgeons, organisational factors or the influence of patients preferences.
A cross-sectional web survey was conducted among 260 Dutch oncological/breast surgeons. Preferences of surgeons and the influence of the patients' preferences were determined by means of best-worst scaling (BWS) of profile case scenarios and by ranking risk factors. The survey also explored organisational questions, the reported use of diagnostic techniques and influences on the decision.
The BWS scenarios were completed by 57 surgeons. The most important reasons for performing SLNB were a suspected invasive component and DCIS grade 3. In the ranking, these were also the first and second most important factor, followed by the size of the lesion and a mass on mammogram. In 58% to 70% of the scenarios, the surgeons would not change their decisions on the use of SLNB if the patient's chose differed. No organisational factor was significantly associated with the reported use of SLNB.
The inter-hospital variation in the use of SLNB could not be attributed to organisational factors or surgeons' preferences for risk factors. The risk factors that most surgeons reported as reasons for performing SLNB are consistent with the factors described in the Dutch treatment guideline for the use of SLNB.
To determine prospectively overall and age-specific estimates of contralateral breast cancer (CBC) risk for young patients with breast cancer with or without BRCA1/2 mutations.
A cohort of 6,294 ...patients with invasive breast cancer diagnosed under 50 years of age and treated between 1970 and 2003 in 10 Dutch centers was tested for the most prevalent BRCA1/2 mutations. We report absolute risks and hazard ratios within the cohort from competing risk analyses.
After a median follow-up of 12.5 years, 578 CBCs were observed in our study population. CBC risk for BRCA1 and BRCA2 mutation carriers was two to three times higher than for noncarriers (hazard ratios, 3.31 95% CI, 2.41 to 4.55; P < .001 and 2.17 95% CI,1.22 to 3.85; P = .01, respectively). Ten-year cumulative CBC risks were 21.1% (95% CI, 15.4 to 27.4) for BRCA1, 10.8% (95% CI, 4.7 to 19.6) for BRCA2 mutation carriers and 5.1% (95% CI, 4.5 to 5.7) for noncarriers. Age at diagnosis of the first breast cancer was a significant predictor of CBC risk in BRCA1/2 mutation carriers only; those diagnosed before age 41 years had a 10-year cumulative CBC risk of 23.9% (BRCA1: 25.5%; BRCA2: 17.2%) compared with 12.6% (BRCA1: 15.6%; BRCA2: 7.2%) for those 41 to 49 years of age (P = .02); our review of published studies showed ranges of 24% to 31% before age 40 years (BRCA1: 24% to 32%; BRCA2:17% to 29%) and 8% to 21% after 40 years (BRCA1: 11% to 52%; BRCA2: 7% to 18%), respectively.
Age at first breast cancer is a strong risk factor for cumulative CBC risk in BRCA1/2 mutation carriers. Considering the available evidence, age-specific risk estimates should be included in counseling.
Here we report for the first time the relation between breast cancer subtypes and 10‐year recurrence rates and mortality in the Netherlands. All operated women diagnosed with invasive non‐metastatic ...breast cancer in 2005 in the Netherlands were included. Patients were classified into breast cancer subtypes according to ER, PR, HER2 status and grade: luminal A, luminal B, HER2 positive and triple negative. Percentages and hazards of recurrence were compared among subtypes. Adjusted 10‐year overall (OS) and recurrence‐free survival (RFS) were calculated using multivariable Cox regression. Of 8,062 patients, 4,482 (56%) were luminal A, 2,090 (26%) luminal B, 504 (6%) HER2 positive and 986 (12%) triple negative. Local recurrences (7.5%) and distant metastases (25.6%) occurred most often in HER2 positive disease and the least often in luminal A (3.7% and 9.5%, respectively). Regional recurrences were most often diagnosed in triple negative disease (5.2%), and the least often in luminal A (1.7%). HER2 positive and triple negative subtypes had the highest recurrence rates in the second year, while luminal A and B showed a more continuous pattern over time, with lobular tumours recurring more often. After adjustment for differences in baseline characteristics, triple negative disease showed worse 10‐year OS and triple negative and HER2 positive disease had the lowest 10‐year RFS. In the Netherlands, breast cancer subtypes are important predictors for 10‐year recurrence rates. Knowledge on recurrence and survival rates according to these different subtypes, in combination with other prognostic factors, can support patient‐tailored treatment and individualised follow‐up.
What's new?
While breast cancer subtypes are known independent predictors of survival and recurrence risk, data on long‐term recurrences in daily practice remain scarce. In this population‐based study reporting on 10‐year recurrences, HER2 positive and triple negative subtypes showed the highest recurrence rates, which occurred most often in the second year, while luminal A and B recurred later on during the follow‐up. Lobular tumours recurred more often than ductal tumours. In the Netherlands, breast cancer subtypes are thus important predictors for 10‐year recurrence rates. Knowledge on recurrence and survival rates according to these different subtypes can help support patient‐tailored treatment and individualised follow‐up.
The COVID-19 pandemic forced the Dutch national breast screening program to a halt in week 12, 2020. In week 26, the breast program was resumed at 40% capacity, which increased to 60% in week 34. We ...examined the impact of the suspension and restart of the screening program on the incidence of screen-detected and non-screen-detected breast cancer. We selected women aged 50–74, diagnosed during weeks 2–35 of 2018 (n = 7250), 2019 (n = 7302), or 2020 (n = 5306), from the Netherlands Cancer Registry. Weeks 2–35 were divided in seven periods, based on events occurring at the start of the COVID-19 pandemic. Incidence of screen-detected and non-screen-detected tumors was calculated overall and by age group, cT-stage, and cTNM-stage for each period in 2020, and compared to the incidence in the same period of 2018/2019 (averaged). The incidence of screen-detected tumors decreased during weeks 12–13, reached almost zero during weeks 14–25, and increased during weeks 26–35. Incidence of non-screen-detected tumors decreased to a lesser extent during weeks 12–16. The decrease in incidence was seen in all age groups and mainly occurred for cTis, cT1, DCIS, and stage I tumors. Due to the suspension of the breast cancer screening program, and the restart at reduced capacity, the incidence of screen-detected breast tumors decreased by 67% during weeks 9–35 2020, which equates to about 2000 potentially delayed breast cancer diagnoses. Up to August 2020 there was no indication of a shift towards higher stage breast cancers after restart of the screening.
•Breast cancer incidence decreased by 37% during weeks 9–35 2020 in women aged 50–74, compared to weeks 9–35 2018/2019.•The incidence of lower stage tumors mainly decreased.•Due to the temporary suspension of the screening program, 67% fewer screen-detected breast tumors have been diagnosed.•The incidence of non-screen-detected tumors was less influenced by the pandemic and decreased only 7% in weeks 9–35 2020.•Up to August 2020 no shift towards a higher tumor stage at diagnosis was seen.