Do LORIS Trial Eligibility Criteria Identify a Ductal Carcinoma In Situ Patient Population at Low Risk of Upgrade to Invasive Carcinoma?

Factors Associated With Underestimation of Invasive Cancer in Patients With Ductal Carcinoma In Situ: Precautions for Active Surveillance

Importance

Recent recognition of the overdiagnosis and overtreatment of ductal carcinoma in situ (DCIS) detected by mammography has led to the development of clinical trials randomizing women with non-high-grade DCIS to active surveillance, defined as imaging surveillance with or without endocrine therapy, vs standard surgical care.

Objective

To determine the factors associated with underestimation of invasive cancer in patients with a clinical diagnosis of non-high-grade DCIS that would preclude active surveillance.

Design, Setting, and Participants

A retrospective cohort study was conducted using records from the National Cancer Database from January 1, 1998, to December 31, 2012, of female patients 40 to 99 years of age with a clinical diagnosis of non-high-grade DCIS who underwent definitive surgical treatment. Data analysis was conducted from November 1, 2015, to February 4, 2017.

Exposures

Patients with an upgraded diagnosis of invasive carcinoma vs those with a diagnosis of DCIS based on final surgical pathologic findings.

Main Outcomes and Measures

The proportions of cases with an upgraded diagnosis of invasive carcinoma from final surgical pathologic findings were compared by tumor, host, and system characteristics.

Results

Of 37 544 women (mean [SD] age, 59.3 [12.4] years) presenting with a clinical diagnosis of non-high-grade DCIS, 8320 (22.2%) had invasive carcinoma based on final pathologic findings. Invasive carcinomas were more likely to be smaller (>0.5 to ≤1.0 cm vs ≤0.5 cm: odds ratio [OR], 0.73; 95% CI, 0.67-0.79; >1.0 to ≤2.0 cm vs ≤0.5 cm: OR, 0.42; 95% CI, 0.39-0.46; >2.0 to ≤5.0 cm vs ≤0.5 cm: OR, 0.19; 95% CI, 0.17-0.22; and >5.0 cm vs ≤0.5 cm: OR, 0.11; 95% CI, 0.08-0.15) and lower grade (intermediate vs low: OR, 0.75; 95% CI, 0.69-0.80). Multivariate logistic regression analysis demonstrated that younger age (60-79 vs 40-49 years: OR, 0.84; 95% CI, 0.77-0.92; and ≥80 vs 40 to 49 years: OR, 0.76; 95% CI, 0.64-0.91), negative estrogen receptor status (positive vs negative: OR, 0.39; 95% CI, 0.34-0.43), treatment at an academic facility (academic vs community: OR, 2.08; 95% CI, 1.82-2.38), and higher annual income (>$63 000 vs <$38 000: OR, 1.14; 95% CI, 1.02-1.28) were significantly associated with an upgraded diagnosis of invasive carcinoma based on final pathologic findings.

Conclusions and Relevance

When selecting patients for active surveillance of DCIS, factors other than tumor biology associated with invasive carcinoma based on final pathologic findings may need to be considered. At the time of randomization to active surveillance, a significant proportion of patients with non-high-grade DCIS will harbor invasive carcinoma.

Outcomes for Women with Minimal-Volume Ductal Carcinoma In Situ Completely Excised at Core Biopsy

BACKGROUND

Overdiagnosis and overtreatment of ductal carcinoma in situ (DCIS) are concerns, especially for women with low-volume, screen-detected DCIS. This study aimed to evaluate the outcomes for such patients.

METHODS

Women who had minimal-volume DCIS (mDCIS, defined as DCIS diagnosed by core biopsy but with no residual disease on the surgical excision) treated with breast-conserving surgery from 1990 to 2011 were identified. Ipsilateral and contralateral breast events (IBE and CBE) were compared by competing-risk (CR) analysis. Kaplan-Meier (KM) estimates and log-rank tests were used to evaluate covariates.

RESULTS

The study identified 290 cases of mDCIS. The median age of the patients was 53 years. Radiation therapy (RT) was performed for 27.6% and endocrine therapy for 16.2% of the patients. The median follow-up period was 6.8 years. Overall, the IBE rates were 4.3% at 5 years and 12.3% at 10 years. Among the women not receiving RT, the 5- and 10-year IBE rates (5.4 and 14.5%) were higher than the CBE rates (1.8 and 2.7%). Among those receiving RT, the IBE rates (1.5 and 6.0%) were lower than the CBE rates (4.1 and 15.6%). The women receiving RT trended toward significantly lower IBE rates (p = 0.07). Age, grade, and endocrine therapy were not significantly associated with IBE risk.

CONCLUSIONS

Among the patients with mDCIS who did not receive RT, the IBE risk was substantially higher than the CBE risk, demonstrating that even DCIS of very low volume is associated with clinically relevant disease. The finding that the IBE risk was greater than the CBE risk supports current strategies that treat DCIS as a precursor rather than a risk marker. Women with mDCIS are not at negligible risk for IBE in the absence of adjuvant therapy.

Surgical Upstaging Rates for Vacuum Assisted Biopsy Proven DCIS: Implications for Active Surveillance Trials

PURPOSE

This study was designed to determine invasive cancer upstaging rates at surgical excision following vacuum-assisted biopsy of ductal carcinoma in situ (DCIS) among women meeting eligibility for active surveillance trials.

METHODS

Patients with vacuum-assisted, biopsy-proven DCIS at a single center from 2008 to 2015 were retrospectively reviewed. Imaging and pathology reports were interrogated for the imaging appearance, tumor grade, hormone receptor status, and presence of comedonecrosis. Subsequent surgical reports were reviewed for upstaging to invasive disease. Cases were classified by eligibility criteria for the COMET, LORIS, and LORD DCIS active surveillance trials.

RESULTS

Of 307 DCIS diagnoses, 15 (5%) were low, 95 (31%) intermediate, and 197 (64%) high nuclear grade. The overall upstage rate to invasive disease was 17% (53/307). Eighty-one patients were eligible for the COMET Trial, 74 for the LORIS trial, and 10 for the LORD Trial, although LORIS trial eligibility also included real-time, multiple central pathology review, including elements not routinely reported. The upstaging rates to invasive disease were 6% (5/81), 7% (5/74), and 10% (1/10) for the COMET, LORIS, and LORD trials, respectively. Among upstaged cancers (n = 5), four tumors were Stage IA invasive ductal carcinoma and one was Stage IIA invasive lobular carcinoma; all were node-negative.

CONCLUSIONS

DCIS upstaging rates in women eligible for active surveillance trials are low (6-10%), and in this series, all those with invasive disease were early-stage, node-negative. The careful patient selection for DCIS active surveillance trials has a low risk of missing occult invasive cancer and additional studies will determine clinical outcomes.

Sentinel lymph node biopsy in low risk settings

BACKGROUND

Sentinel lymph node biopsy (SLNB) should be performed in patients with ductal carcinoma in situ (DCIS) undergoing mastectomy. Yet, the same logic is controversial in the setting of prophylactic mastectomy.

METHODS

Surgeons were surveyed as to their practices. Statistical analyses were performed to identify associated factors.

RESULTS

238 surgeons responded to the survey. 73.1% of respondents stated they would always perform SLNB in the setting of mastectomy for DCIS, but only 6.6% would always do so in the prophylactic setting. While generally perceived that the rate of SLN positivity in the setting of pure DCIS and prophylactic mastectomy was <5% (96.9% and 99.5%, respectively), 61.8% of surgeons who reported "always" performing SLNB in the setting of DCIS treated with mastectomy stated they "never" performed a SLNB for prophylactic mastectomy.

CONCLUSION

SLNB practice patterns for these low risk settings are disparate. Consensus is required to rationalize practice.

Current controversies in radiotherapy for breast cancer

Multimodal treatment approaches have substantially improved the outcome of breast cancer patients in the last decades. Radiotherapy is an integral component of multimodal treatment concepts used in curative and palliative intention in numerous clinical situations from precursor lesions such as ductal carcinoma in situ (DCIS) to advanced breast cancer. This review addresses current controversial topics in radiotherapy with special consideration of DCIS, accelerated partial breast irradiation (APBI) and regional nodal irradiation (RNI) and provides an update on the clinical practice guidelines of the Breast Cancer Expert Panel of the German Society of Radiation Oncology (DEGRO).

Women with Low-Risk DCIS Eligible for the LORIS Trial After Complete Surgical Excision: How Low Is Their Risk After Standard Therapy?

BACKGROUND

Identifying DCIS patients at low risk for disease progression could obviate need for standard therapy. The LORIS (surgery versus active monitoring for low-risk DCIS) trial is studying the safety of monitoring low-risk DCIS, although ipsilateral breast tumor recurrence (IBTR) rates in patients meeting enrollment criteria after complete surgical excision are unknown.

METHODS

Women with pure DCIS treated with breast-conserving surgery (BCS) with/without radiation therapy (RT) from 1/1996-1/2011 were included from a prospectively maintained database. IBTR rates were compared between those who did and did not meet LORIS eligibility criteria (age ≥ 46 years, screen-detected calcifications, nipple discharge absence, minimal family history, non-high-grade DCIS) after complete surgical excision.

RESULTS

A total of 2394 women were identified; 401 met LORIS criteria. Median follow-up was 5.9 years; 431 had ≥10 years follow-up. LORIS cohort median age was 61 years (range 46-86 years); 207 (52 %) underwent RT, 79 (20 %) received endocrine therapy. Of 401 patients, 24 experienced an IBTR. Overall 10-year IBTR rates were 10.3 % (LORIS) versus 15.4 % (non-LORIS) (p = 0.08); without RT, 12.1 versus 21.4 %, respectively (p = 0.06). The 10-year invasive-IBTR rates for women meeting LORIS criteria were: 5.3 % BCS overall, 6.0 % without RT.

CONCLUSIONS

Women meeting LORIS criteria (after complete surgical excision) are at somewhat lower risk for IBTR. Among such women undergoing excision without RT, the 10-year invasive-IBTR rate was 6 %. Given that approximately 20 % of women with core biopsy-proven non-high-grade DCIS have invasive cancer at excision, women managed without excision would be expected to incur higher invasive cancer rates. Additional criteria are needed to identify women not requiring intervention for DCIS.

Ductal carcinoma in situ: Is core needle biopsy ever enough?

INTRODUCTION

This study investigates the rate of histological underestimation of invasive breast carcinoma following diagnosis of ductal carcinoma in situ (DCIS) on a radiologically guided core needle biopsy, and factors that may influence this upgrade rate.

METHODS

A retrospective review of the results of breast core biopsies performed between 1st January, 2005 and 2nd July, 2014 was conducted, and those with a diagnosis of DCIS were identified. Data including final excision pathology, lesion size, performing radiologist, core biopsy system and guidance method used were collected and included in the analysis.

RESULTS

We report an overall upgrade rate to invasive cancer of 20.5% (95% CI = 16.1-24.9%). No statistically significant relationship was identified between biopsy systems used or clinicians performing the biopsies and the rate of upgrade to invasive cancer. Initially a statistically significant relationship was demonstrated between upgrade rates and lesion size, DCIS grade, as well as guidance method. Subsequent multivariable analysis showed no statistically significant relationship between guidance method and upgrade rates but a trend towards statistical significance (P < 0.1).

CONCLUSION

Our recommendation is to inform women diagnosed with DCIS preoperatively in our programme, that there is a one in five chance the diagnosis will prove to be invasive cancer on definitive surgery. This is particularly important for women contemplating whether or not to undergo surgery for DCIS. Additionally, as the most significant predictor of upgrade rate demonstrated in this study is increasing lesion size, consideration should be given to increasing the number of core samples taken of larger lesions.