Analysis of Local Recurrence Risk in Ductal Carcinoma In Situ and External Validation of the Memorial Sloan Kettering Cancer Center Nomogram

BACKGROUND

Adjuvant radiotherapy and hormonotherapy after breast-conserving surgery (BCS) in ductal carcinoma in situ (DCIS) have been shown to reduce the risk of local recurrence. To predict the risk of ipsilateral breast tumor relapse (IBTR) after BCS, the Memorial Sloan Kettering Cancer Center (MSKCC) developed a nomogram to analyze local recurrence (LR) risk in our cohort and to assess its external validation.

METHODS

A historical cohort study using data from 296 patients treated for DCIS at the Hospital Clínic of Barcelona was carried out. Patients who had had a mastectomy were excluded from the analysis.

RESULTS

The mean age was 58 years (42-75), and the median follow-up time was 10.64 years. The overall local relapse rate was 13.04% (27 patients) during the study period. Actuarial 5- and 10-year IBTR rates were 5.8 and 12.9%, respectively. The external validation of the MSKCC nomogram was performed using a multivariate logistic regression analysis on a total of 207 patients, which did not reach statistical significance in the studied population for predicting LR (p = 0.10). The expression of estrogen receptors was significantly associated with a decreased risk of LR (OR: 0.25; p = 0.004).

CONCLUSIONS

In our series, the LR rate was 13.4%, which was in accordance with the published series. The MSKCC nomogram did not accurately predict the IBTR in this Spanish cohort of patients treated for DCIS (p = 0.10).

Chronic toxicity and long-term outcome in intraoperative electron radiotherapy as boost followed by whole-breast irradiation

PURPOSE

The administration of a dose boost to the tumor bed after breast-conserving surgery has proven to reduce local recurrence. Intra-operative electron radiotherapy (IOERT) offers an alternative method to deliver a boost with several advantages, such as direct visualization of the tumor bed, less inter- and intrafraction motion and a reduction in the number of medical appointments. The objective of our study is to assess chronic toxicity and long-term outcome for our patients after IOERT boost.

MATERIAL AND METHODS

Forty-six patients treated at our institution between July 2013 and June 2020 with IOERT boost during Breast-Conserving Surgery and consecutive whole breast irradiation were prospectively analyzed. A 10-12 Gy boost was prescribed to 42 patients and 4 patients received a 20 Gy boost. An analysis for overall survival, local relapse and distant progression was performed. Acute and chronic toxicity was assessed by CTCAE 4.0.

RESULTS

The median age was 64.5 years (40-90). The median follow-up was 62 months (4-86). We had no local recurrences but 2 patients (4.3%) presented a distant recurrence. Mean pathological tumor size was 16 mm (6-52). 84.8% (39) of the patients had invasive ductal carcinoma. 52.2% (24) presented histological grade II. 52.2% (24) were Luminal A like, 21.7% (10) Luminal B like, 13% (6) HER2 positive, 13% (6) triple negative. No Grade 3-4 chronic toxicity was observed. Grade 1-2 fibrosis was evidenced in 13% (6) of the patients, 4.3% (2) patients presented fat necrosis, 6.5% (3) presented seroma, 4.3% (2) had localized pain, 2.2% (1) presented localized hematoma and 2.2% (1) presented localized edema.

CONCLUSIONS

IOERT boost in breast cancer treatment during BCS is a safe option with low chronic toxicity. The recurrence rates are comparable to published data and emphasize that IOERT as boost is an effective treatment.

Neoadjuvant Systemic Therapy in Breast Cancer: Association of Contrast-enhanced MR Imaging Findings, Diffusion-weighted Imaging Findings, and Tumor Subtype with Tumor Response

Purpose To investigate the performance of tumor subtype and various magnetic resonance (MR) imaging parameters in the assessment of tumor response to neoadjuvant systemic therapy (NST) in patients with breast cancer and to outline a model of pathologic response, considering pathologic complete response (pCR) as the complete absence of any residual invasive cancer or ductal carcinoma in situ (DCIS). Materials and Methods This was an institutional review board-approved retrospective study, with waiver of the need to obtain informed consent. From November 2009 to December 2014, 111 patients with histopathologically confirmed invasive breast cancer who were undergoing NST were included (mean age, 54 years; range, 27-84 years). Breast MR imaging was performed before and after treatment. Presence of late enhancement was assessed. Apparent diffusion coefficients (ADCs) were obtained by using two different methods. ADC ratio (mean posttreatment ADC/mean pretreatment ADC) was calculated. pCR was defined as absence of any residual invasive cancer or DCIS. Multivariate regression analysis and receiver operating characteristic analysis were performed. Results According to their immunohistochemical (IHC) profile, tumors were classified as human epidermal growth factor receptor 2 (HER2) positive (n = 51), estrogen receptor (ER) positive/HER2 negative (n = 40), and triple negative (n = 20). pCR was achieved in 19% (21 of 111) of cases; 86% of them were triple-negative or HER2-positive subtypes. Absence of late enhancement at posttreatment MR imaging was significantly associated with pCR (area under the curve [AUC], 0.85). Mean ADC ratio significantly increased when pCR was achieved (P < .001). A κ value of 0.479 was found for late enhancement (P < .001), and the intraclass correlation coefficient for ADCs was 0.788 (P < .001). Good correlation of ADCs obtained with the single-value method and those obtained with the mean-value methods was observed. The model combining the IHC subtype, ADC ratio, and late enhancement had the highest association with pathologic response, achieving an AUC of 0.92 (95% confidence interval: 0.86, 0.97). Conclusion Triple-negative or HER2-positive tumors showing absence of late enhancement and high ADC ratio after NST are associated with pCR. ^© RSNA, 2016 Online supplemental material is available for this article.

Added value of intraoperative real-time imaging in searches for difficult-to-locate sentinel nodes

Localization of sentinel lymph nodes can be challenging if they are in difficult anatomic locations or near high radiotracer activity. The purpose of this study was to assess the value of intraoperative real-time imaging using a portable gamma-camera in conjunction with a conventional gamma-counting probe when it is difficult to localize the sentinel node.

METHODS

After (99m)Tc-nanocolloid injection, patients with various malignancies underwent presurgical lymphoscintigraphy followed by surgery (usually the next day). We evaluated 20 patients who required sentinel lymph node biopsy and in whom the location or other characteristics of the sentinel node would make intraoperative retrieval difficult. During surgery, the sentinel node was localized using a portable gamma-camera together with a hand-held gamma-probe. A (153)Gd pointer or (125)I seed was used to better depict the sentinel node location in real time.

RESULTS

Using only a conventional hand-held gamma-probe, surgeons were able to definitively localize the sentinel node in 15 of 20 patients. Intraoperatively, the portable gamma-camera showed uptake by the definite sentinel node in 19 of 20 patients and helped to precisely localize the node with the hand-held gamma-probe in 4 patients. In 1 of these patients, the sentinel node was metastatic.

CONCLUSION

The combination of a standard hand-held gamma-probe and real-time imaging provided by a portable gamma-camera offers a high intraoperative detection rate in patients with difficult sentinel node localization as assessed by presurgical lymphoscintigraphy.

Radiologic and pathologic findings in breast tumors with high signal intensity on T2-weighted MR images

Various histopathologic components in benign and malignant breast lesions may generate hyperintense signal at T2-weighted magnetic resonance (MR) imaging. A comparison of the specific histologic features found in breast lesions with a high-signal-intensity appearance on unenhanced T2-weighted turbo spin-echo MR images obtained without spectral fat suppression shows that this MR imaging characteristic is often suggestive of the differential diagnosis. Histopathologic features that may produce high signal intensity in breast lesions include extensive necrosis, a cystic or microcystic component, an adipose or sebaceous component, mucinous stroma, loose myxoid stroma, stromal edema, and hemorrhagic changes. A more nuanced understanding of the correlation between the MR imaging appearance and specific pathologic findings may help radiologists achieve earlier and more accurate differentiation among this group of breast lesions.