Abstract PD4-03: MRI detection of residual disease following neoadjuvant chemotherapy (NAC) in the I-SPY 2 TRIAL

Background: Detecting residual disease accurately using MRI after NAC to identify both responders and non-responders is essential for de-escalating therapy or redirecting patients to more effective treatment. The purpose of this study is to determine if the combination of longest diameter (LD) and functional tumor volume (FTV) from dynamic contrast enhanced (DCE-) MRI is superior to FTV alone or LD alone for assessing treatment response after neoadjuvant therapy in breast cancer patients.

Methods: Data from patients in the graduated drug arms of the I-SPY 2 trial were included in the analysis. Both LD and FTV were assessed using DCE-MRI after neoadjuvant therapy. LD was measured by the site radiologist as the longest dimension of the enhanced area on early post-contrast images. Functional tumor volume (FTV) was assessed as the sum of voxels with enhancement above specific thresholds within the pre-defined region-of-interest (ROI). A linearized variable was derived to represent the combination of FTV and LD. The area under the receiver operating characteristic curve (AUC) was used to evaluate the assessment of treatment response, pathologic complete response (pCR), defined as no invasive disease in the breast and lymph nodes, and in-breast pCR, defined as no invasive disease in the breast only. The analysis was performed in the full cohort and in breast cancer subtype defined by hormone receptor status and HER2 status.

Results: Among the patient cohort of N=675 with FTV and LD, 247 (37%) did and 428 (41%) did not achieve pCR after neoadjuvant therapy. pCR rates varied among HR/HER2 subtypes (HR+/HER2-: 19%; HR+/HER2+: 38%; HR-/HER2+: 71%; HR-/HER2- (triple negative, TN): 43%). In-breast pathologic complete response rates were slightly higher in each group (full: 41%; HR+/HER2-: 23%; HR+/HER2+: 43%; HR-/HER2+: 72%; HR-/HER2-: 49%). Table 1 shows AUCs for assessing pCR using FTV alone, LD alone, and the variable combining FTV and LD. Higher AUCs were observed in all patient groups using the combined variable. AUC of 0.79 (95% CI: 0.77, 0.81) was observed for the combined variable to assess pCR in the full cohort. AUCs varied from 0.69 to 0.86 among HR/HER2 subgroups (HR+/HER2-: 0.69; HR+/HER2+: 0.74; HR-/HER2+: 0.86; HR-/HER2-: 0.80), with no difference in assessing pCR or in-breast pCR. The performance is best for the HR- subtypes.

Conclusions: Both FTV and LD can be used in the assessment of invasive disease residual after neoadjuvant therapy. The combined variable of FTV and LD achieved highest AUCs, compared to using individual variable alone. Tools to improve performance in the HR+ subsets are underway.

AUCs of MR measurements for identifying pCR  FTV alone (95% CI)LD alone (95% CI)Combined (95% CI)FullWith subtype adj.0.73 (0.71, 0.75)0.77 (0.74, 0.79)0.79 (0.77, 0.81)FullWithout subtype adj0.69 (0.65, 0.73)0.72 (0.68, 0.76)0.75 (0.71, 0.79)HR+/HER2- 0.68 (0.60, 0.77)0.68 (0.59, 0.77)0.69 (0.61, 0.77)HR+/HER2+ 0.65 (0.56, 0.75)0.72 (0.64, 0.80)0.74 (0.66, 0.82)HR-/HER2+ 0.69 (0.55, 0.83)0.82 (0.71, 0.92)0.86 (0.77, 0.95)HR-/HER2- (TN) 0.72 (0.66, 0.79)0.73 (0.67, 0.80)0.80 (0.74, 0.85)

Citation Format: Li W, Newitt D, Yun BL, Kornak J, Joe B, Yau C, Abe H, Wolverton D, Crane E, Ward K, Nelson M, Niell B, Drukteinis J, Oh K, Brandt K, Bang DH, Ojeda H, Eghtedari M, Sheth P, Bernreuter W, Umphrey H, Rosen M, Dogan B, Yang W, Esserman L, Hylton N. MRI detection of residual disease following neoadjuvant chemotherapy (NAC) in the I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD4-03.

Abstract P3-03-03: A tri-modality imaging assessment algorithm to evaluate neoadjuvant therapy response in patients with operable breast cancer

Background: To determine the negative predictive value (NPV), positive predictive value (PPV), accuracy, sensitivity and specificity of a pre-surgical tri-modality imaging assessment algorithm to determine complete pathologic response (pCR) post neoadjuvant therapy in patients with operable breast cancer.

Methods: A retrospective analysis was performed on data collected from patients receiving neoadjuvant therapy and pre-surgical breast magnetic resonance imaging (MRI), ultrasound (US) and mammography between 2004 and 2010 at our institution. Tri-modality imaging was reviewed by a single blinded breast radiologist and evaluated for predetermined modality specific parameters as defined in Table 1. The NPV, PPV, accuracy, sensitivity, and specificity were calculated on the basis of the final surgical pathology report with a complete pathologic response in the breast defined as no residual invasive disease or in situ disease.

Results. Eighty-three tumors in 83 patients with a mean age of 50 (range 27–70) were evaluated. Twenty-three patients had a pCR. The NPV, PPV, sensitivity, specificity, and accuracy of tri-modality imaging algorithm for pCR were 0.87, 0.95, 0.95, 0.87 and 0.93 utilizing a cut-point of ≤ 5 for complete response by imaging. The mean score for patients with pCR was 4.61 (range 3–10) with 3 patients scoring above 5. The mean score for patients with residual disease was 7.73 (range 5–11).

Conclusions: A tri-modality imaging scoring algorithm is predictive of complete pathologic response. This algorithm will be tested in a developing prospective trial that will also assess the additive value of tumor bed biopsy in patients who achieve a score of 5 or less.

Abstract P1-12-04: Long Term Follow-Up of a Pilot Trial of Pre-Operative (Neoadjuvant) Letrozole in Combination with Bevacizumab in Post-Menopausal Women with Newly Diagnosed Estrogen and/or Progesterone Receptor Positive Breast Cancer

Introduction: Overexpression of vascular endothelial growth factor (VEGF) in breast cancer tumors has been associated with resistance to anti-estrogen adjuvant therapy. We designed a pilot study of neoadjuvant letrozole and bevacizumab (anti-VEGF) to assess feasibility and short term efficacy in post-menopausal women with stage II/III, ER/PR positive breast cancer. Patients and Methods: Patients were treated with a neoadjuvant regimen of letrozole, 2.5 mg/day (PO) and bevacizumab 15 mg/kg every 3 weeks (IV) for a total of 24 weeks prior to surgical treatment of their breast cancer. Patients were followed for toxicity at three week intervals and tumor assessment (physical exam and tumor ultrasound) at six week intervals. Results: Twenty-five evaluable patients were treated. The regimen was well tolerated except for two patients who were taken off-study for difficult to control hypertension. Objective clinical response occurred in 17/25 patients (68%) including 16% CR and 52% PR. The four patients with clinical CR had pathologic CR in their breasts (16%) although one had residual tumor cells in axillary nodes. Two of the 17 responding patients were lost to follow-up; with a median follow-up of 50 months, no relapses have been seen in the 15 responsive patients, including 10 patients who received no adjuvant chemotherapy. Two patients with progressive disease at 9 and 16 weeks received neoadjuvant chemotherapy, surgery and radiation. One of these patients relapsed at 35 months and the other is NED at 44 months. Four patients had stable disease and all received adjuvant chemotherapy; one patient relapsed at 25 months, and the reminder are NED at 44-52 months. Overall, 2 out of 21 patients with adequate follow-up had disease reoccurrence (9.5%) at a median follow-up of 45 months. Conclusion: Combination neoadjuvant therapy with letrozole and bevacizumab was well tolerated and resulted in impressive clinical and pathologic responses. Data suggest that patients having an objective response to neoadjuvant therapy had excellent 4 year disease-free survival (100%) while relapsed occurred in 2 out of 6 patients who failed to have an objective response despite additional neoadjuvant or adjuvant chemotherapy. The Breast Cancer Translational Research Consortium has an ongoing randomized phase II trial of letrozole ± bevacizumab in this patient population.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-12-04.

A Pilot Trial of Pre-Operative (Neoadjuvant) Letrozole in Combination with Bevacizumab in Post-Menopausal Women with Newly Diagnosed Estrogen and/or Progesterone Receptor Positive Breast Cancer

Purpose Tumor content or expression of vascular endothelial growth factor (VEGF) is associated with impaired efficacy of anti-estrogen adjuvant therapy. We designed a pilot study of neoadjuvant letrozole and bevacizumab (anti-VEGF) to assess feasibility and short term efficacy in post-menopausal women with stage II/III, ER/PR positive breast cancer. Patients and Methods Patients were treated with a neo-adjuvant regimen of letrozole, 2.5mg/day (P.O.) and bevacizumab 15mg/kg Q3 weeks (I.V.) for a total of 24 weeks prior to surgical treatment of their breast cancer. Patients were followed for toxicity at 3 week intervals and tumor assessment (physical exam and tumor ultrasound) at 6 week intervals. PET scans were carried out prior to therapy and 6 weeks after initiation of therapy. Surgery was done 4 weeks after the last dose of bevacizumab. Results Twenty five evaluable patients were treated. The regimen was well tolerated except for 2 patients who were taken off-study for difficult to control hypertension. Objective clinical response occurred in 17/25 patients (68%) including 16% CR and 52% PR. The 4 patients with clinical CR had pathologic CR in their breasts (16%) although one had residual tumor cells in axillary nodes. 8/25 patients (32%) attained stage 0 or 1 status. PET scan response at 6 weeks correlated with clinical CR and breast pathologic CR at 24 weeks (p < 0.0036). Conclusion Combination neo-adjuvant therapy with letrozole and bevacizumab was well tolerated and resulted in impressive clinical and pathologic responses. The Breast Cancer Translational Research Consortium has an ongoing randomized phase II trial of this regimen in this patient population.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1088.

The Accuracy of MRI in Predicting Pathologic Complete Response in Invasive Breast Cancer Patients Receiving Neoadjuvant Systemic Treatment

Background: Magnetic resonance imaging (MRI) has increased sensitivity to detect abnormalities in breast tissue as compared with mammography or ultrasound. Published reports of MRIs ability to predict pathologic response to neoadjuvant chemotherapy have shown conflicting results that vary depending on baseline molecular characteristics and chemotherapeutic regimens, with some studies suggesting higher predictive accuracy in Her2 positive patients receiving trastuzumab. This study examines both the ability of MRI to predict pathologic response and how tumor molecular profiles and treatment regimens influence MRI sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Sensitivity, specificity, PPV, and NPV for the combination of post-treatment mammogram, ultrasound, and MRI studies in predicting pathologic complete response (pCR) was also explored.Methods: Eighty-one patients with invasive breast cancer treated with neoadjuvant systemic therapy between 2002 to 2009 and imaged pre and post-treatment with breast MRI were reviewed. Patient, tumor, and treatment characteristics including tumor grade, histologic type, receptor status (ER, PR, and Her2), breast cancer subtype [luminal A, luminal B, Her2 positive, triple negative (TN)], correlative pre- and post-treatment mammographic and ultrasound imaging, drug regimen, and pathologic findings were recorded. Complete pathologic response was defined as no residual invasive or pre-invasive disease in the breast.Results: Patients had the following subtypes of breast cancer: 21/81 (26%) luminal A, 13/81 (16%) luminal B, 23/81 (28%) Her2 positive, and 24/81(30%) TN. Of the Her2 positive, only 12/23 (52%) treated after May 2005 received adjuvant trastuzumab. Twenty patients (25%) had a complete radiographic response (rCR) on post-treatment MRI and 23/81(28%) had a pCR. The sensitivity, specificity, PPV, and NPV of MRI for predicting pathologic response was 57%, 88%, 65%, and 84%, respectively. Analysis of breast cancer subtype did not demonstrate a predilection in any particular subtype for correlation of radiographic and pathologic response, although MRI sensitivity (100%) and NPV (100%) were highest in luminal A disease, and specificity and PPV were highest for patients with ER negative (96% and 90%) and triple negative (100% and 100%) disease, respectively. Mammographic and ultrasound post-treatment findings of residual disease did not significantly correlate with pathologic findings in the setting of a rCR on MRI. Multivariate analysis of factors potentially influencing MRIs sensitivity and specificity failed to show that tumor characteristics (ER status, PR status, HER2 status) or neoadjuvant treatment (ACT vs other or trastuzumab) had any effect on these parameters.Conclusions: MRI has the highest specificity and PPV in the setting of ER negative and TN breast cancer. Although treatment results and breast cancer subtype did not influence the sensitivity, specificity, PPV, or NPV of MRI in predicting pathologic response, only half of the Her2 positive subset received trastuzumab. Results from an ongoing large multi-institutional study will further clarify these results.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4022.

MRI tumor volume for predicting response to neoadjuvant chemotherapy in locally advanced breast cancer: Findings from ACRIN 6657/CALGB 150007

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Background: American College of Radiology Imaging Network (ACRIN) trial 6657, the imaging component of the I-SPY trial (CALGB 150007/150012), is testing MRI for predicting response to treatment and stratifying risk-of-recurrence in patients with locally-advanced breast cancer. We report preliminary results evaluating MRI for prediction of pathologic response. Methods: Women with ≥3 cm invasive breast cancer receiving neoadjuvant chemotherapy (NACT) with anthracycline-cyclophosphamide (AC) followed by a taxane (T) were enrolled from May 2002 to March 2006. MRI was performed prior to NACT (t1), after 1 cycle AC (t2), between AC and T (t3), and following T prior to surgery (t4). MRI tumor size assessments included longest diameter (MRLD) and tumor volume (MRVol). Clinical size (clinsize) and mammographic longest diameter (MGLD) were also recorded. Linear dimension was measured by the radiologist for MGLD and MRLD; MRVol was calculated by computer using signal enhancement ratio (SER) thresholds. Change in clinical and MRI variables at t2 were compared for ability to predict pathologic complete response (pCR). Results: 237 patients were enrolled at 9 institutions. 216 patients with complete imaging were analyzed. Of tumor size measurements at t4, MRVol showed the strongest correlation with pathsize among clinsize (r = 0.44), MGLD (ns), MRLD (r = 0.28) and MRVol (r = 0.61). Early change in MRVol measured at t2 was the only variable predictive of pCR among clinsize (p = 0.14, 0.15), MRLD (p = 0.40, 0.07), MRVol (p = 0.02, 0.01) and peak SER (p = 0.53, 0.72) in univariate and multivariate logistic regression, respectively. Conclusions: Tumor response measured volumetrically by MRI is a stronger and earlier predictor of pathologic response after NACT than clinical exam or tumor diameter. This work is funded by NIH/ACRIN U01 CA79778; CALGB CA31946, CA33601; NCI SPORE CA58207.

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Three-dimensional reconstruction system for imaging of the temporomandibular joint using magnetic resonance imaging

This study was undertaken to develop a three-dimensional reconstruction system using magnetic resonance (MR) images in order to visualize three-dimensional images of the temporomandibular joint (TMJ) including the disk. The computerized reconstruction program (written using Visual Basic for Windows, Microsoft Corp.) could reliably generate three-dimensional images of the TMJ. Image processing techniques made the tracing of images unnecessary, reduced complex human manipulation and associated measurement errors. This system, capable of treating fifty thousand pixels or more, generates smooth three-dimensional images of the TMJ.

Cartilage imaging in osteoarthritis

Osteoarthritis (OA) is the most common articular disorder encountered worldwide. Its successful evaluation (and eventual treatment) depends on establishing a set of criteria for measuring disease progression. An ideal measurement would evaluate changes in articular cartilage, where the primary pathology of the disease takes place. Plain radiographs are the simplest and most readily employable means of joint evaluation, and now microfocal radiographs have been developed, which magnify the radiograph and help portray the joint space more accurately. However, radiography, along with nuclear medicine scans, arthrography, and computed tomography (CT) scans, are limited in their use because they are unable to detect early cartilage abnormalities. Magnetic resonance imaging (MRI) has the advantages of multiplanar imaging, soft tissue contrast, and noninvasiveness. Like radiography, MRI can underestimate the extent of cartilage abnormality. The most sensitive technique for measuring superficial articular abnormalities is arthroscopy, and small-bore arthroscopes are being used to assess knee damage in conscious, nonsedated patients. However, it is not yet clear if arthroscopy can detect subtle changes over time, and vision can be blocked by cloudy synovial fluid. Finally, although it is usually well tolerated, arthroscopy is an invasive technique.

Successful delivery of mature twins after a ruptured interstitial heterotopic pregnancy. A case report

A 31-year-old primigravida had a combined pregnancy consisting of intrauterine twins and an interstitial ectopic after in vitro fertilization/embryo transfer. The patient underwent repair of the ectopic pregnancy at 15 weeks of gestation, with subsequent delivery of mature twins close to term.

Leiomyosarcoma of bone. A clinicopathologic, immunohistochemical, and ultrastructural study of five cases

The authors identified five leiomyosarcomas (LMS) in a review of 13 nonmatrix-producing spindle cell sarcomas of bone. Only two were initially recognized as LMS; the others had been diagnosed as malignant fibrous histiocytoma (two) and fibrosarcoma (one). The patients, four of whom were women, ranged in age from 32 to 70 years. Sites included proximal humerus (two), distal femur (two), and rib (one). All tumors presented with clinical and radiographic features consistent with a diagnosis of primary bone neoplasms, although one probably represented a solitary metastasis from a primary uterine LMS. Radiographs showed lytic bone destruction with a moth-eaten appearance, and three cases had soft tissue extension. Histologically, all tumors showed broad, interlacing fascicles of spindle cells with pleomorphic nuclei, frequent mitoses, and necrosis. Two cases had a focal storiform pattern and bizarre multinucleated cells, and two other cases had focally prominent osteoclast-like giant cells. Extensive immunoreactivity for muscle actin was seen in all cases and for desmin in three. In each case, electron microscopy showed definite smooth muscle differentiation including cytoplasmic filaments with densities. At this writing, two patients are free of disease (including the patient with a presumed metastasis), one is alive with locally recurrent disease, and two are dead of disease. Experience suggests that LMS of bone is a distinct clinicopathologic entity that may be more common than previously recognized. Application of immunohistochemistry and electron microscopy to nonmatrix-producing bone sarcomas should facilitate diagnosis of additional cases.

Melanotic schwannoma. Clinicopathologic, immunohistochemical, and ultrastructural features of a rare primary bone tumor

The authors report a 35-year-old woman who presented with a lytic and blastic tumor of the ilium with soft tissue extension. The resected tumor showed light microscopic and ultrastructural features characteristic of a melanotic schwannoma. An unusual histologic finding was the presence of laminated concretions resembling psammoma bodies. Immunohistochemical stains for S-100, HMB-45, and vimentin were strongly positive. The patient is free of disease 18 months after complete surgical excision.

Orthodontic appliances and magnetic resonance imaging of the brain and temporomandibular joint

Experimental and clinical studies find that orthodontic appliances can produce artifacts in MRI, mostly in the facial region. Removal of removable components, especially archwires, with close checking of the security of banded and bonded attachments, should be sufficient in most cases requiring this diagnostic procedure.