Abstract P2-01-05: A phase II clinical trial of VST-1001 (dilute fluorescein) in lymphatic mapping and sentinel lymph node localization in clinically node negative breast cancer

Background: Combined use of a radiocolloid and a vital blue dye is recommended for accurate lymphatic mapping and sentinel lymph node (SLN) identification in breast cancer. However, vital blue dyes can cause tattooing, skin necrosis and severe allergic reactions. Moreover, the vital blue dyes are only able to detect 70% or less of SLNs in large multi-center trials. Hence, there is an unmet need to develop new lymphatic mapping agents that could potentially replace vital blue dyes. We have previously, in a Phase I trial, reported on the safety of VST-1001 (dilute fluorescein) in SLN identification. Here we report the Phase II data of VST-1001 and direct visualization devices in lymphatic mapping, SLN identification, and safety in clinically node negative breast cancer.

Methods: This prospective Phase II, multi-center, non-randomized, single-arm, open-label, single-dose clinical trial enrolled patients (pts) with DCIS and clinical stage I/II breast cancer eligible for SLN biopsy. All pts had SLN localization with technetium-99m-sulfur colloid (Tc99mSC) and intraoperative lymphatic mapping with 0.1% VST-1001 injected peritumorally, periareolarly, and/or intradermally. SLN radioactivity was identified with a gamma probe, and VST-1001 fluorescence was induced by light emitting diodes and detected as yellowish-green fluorescence in the visible light range with notch filter spectacles. The primary endpoint was the ability of VST-1001 to localize lymph nodes. SLN concordance of Tc99mSC radioactivity and VST-1001 fluorescence, and safety were also assessed.

Results: Eighty-seven women and 2 men with a median age of 60 yrs (range, 37-77) were enrolled. Primary tumor T-stage was: 12.4% T0, 62.9% T1, 23.6% T2, and 1.1% T3. Of the 89 pts, 87 (97.8%) had at least 1 radioactive SLN, and 86 (96.6%) at least 1 fluorescent SLN. Of a total of 198 SLN identified (mean 2.2 SLN/pt), 74.2% were fluorescent and radioactive, 11.6% were radioactive only, 8.6% were fluorescent only, and 5.1% were not radioactive or fluorescent. 82.8% of all SLNs were fluorescent. Twelve (13.5%) pts had microscopic metastatic breast cancer in 14 (7.1%) SLNs. Of the 14 SLNs with metastasis, 12 (85.7%) were both radioactive and fluorescent, 1 (7.1%) fluorescent only and 1 (7.1%) not radioactive or fluorescent and only suspicious on palpation. The fluorescent only SLN was identified in a patient with only 1 SLN and without VST-1001 the metastasis would have been missed. The only adverse event related to VST-1001 was intraoperative grade 2 allergic reaction of the ipsilateral breast in one pt. Intravenous anti-histamines were administered and the erythema resolved.

Conclusions: VST-1001 safely localized lymph nodes in breast cancer. VST-1001 was able to localize lymph nodes that were not radioactive and had a high co-localization concordance with Tc99mSC. VST-1001 also appears to have a higher rate of SLN localization compared to that historically reported for vital blue dyes. In light of these data, VST-1001 may be an alternative SLN localizing agent to be used in conjunction with Tc99mSC in breast cancer pts, eliminating many of adverse events observed when using vital blue dyes without compromising SLN identification.

Citation Format: Ross MI, Black DM, Mittendorf EA, Porretta JM, Bedrosian I, Caudle AS, Hwang RF, Meric-Bernstam F, Babiera GV, Brulotte M, Andtbacka RHI, Matsen CB. A phase II clinical trial of VST-1001 (dilute fluorescein) in lymphatic mapping and sentinel lymph node localization in clinically node negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-01-05.

Abstract P2-10-05: PowerPIINC trial: Changes in tumor proliferation index and quality of life with 7 days of preoperative tamoxifen

BACKGROUND: A decrease in Ki67 has been shown to be a predictor of response to tamoxifen. Previous trials have shown a decreased Ki67 proliferation index in breast tumors with as little as 2 weeks of preoperative tamoxifen. However, shortening the preoperative treatment time in window of opportunity studies increases patient acceptance for trial participation. The POWERPIINC trial examined the effect of 7 days of preoperative tamoxifen on breast tumor proliferation and patient symptoms.

METHODS: Adult women with untreated stage I or II invasive breast cancer that was ER positive (>1%) planning on breast surgery with no contraindications to tamoxifen were enrolled. Women received 20mg of tamoxifen for 7 days up to the day of surgery and for 14 days afterwards. Proliferation was assessed by Ki67 immunohistochemistry before and after 7 days of tamoxifen. The proliferation genes from the PAM50 were also assessed by RT-PCR. Symptoms and QOL were assessed by the FACT-ES, MENQoL, and BMQ.

RESULTS: 52 women were enrolled, and 44 were evaluable for Ki67. The median age was 58.5 years, and the median tumor diameter was 1.2cm. Most women (73%) were post-menopausal. Most tumors were PR positive (88%). Only 8% of tumors were HER2-positive. The Ki67 decreased by a geometric mean of 40% (95% CI 29%-63%), and 73% (95% CI 57%-85%) of women had tumors with decreased proliferation after 7 days of tamoxifen (p=0.0001 by paired t-test). No correlation was seen between the change in Ki-67 and change in FACT-ES or MENQoL scores. Women reported minimal to no bother from psychosocial or physical symptoms at baseline or on the day of surgery. Expression level of individual proliferation genes did not change after 7 days of tamoxifen.

CONCLUSION: Seven days of tamoxifen showed a similar relative decrease in the Ki67 proliferation index as that reported for longer courses. Therefore, short window of opportunity trials can be informative.

Citation Format: Cohen AL, Factor RE, Mooney K, Wade M, Serpico V, Salama M, Nelson E, Porretta J, Matsen C, Ostrander E, Bernard P, Boucher K, Neumayer L. PowerPIINC trial: Changes in tumor proliferation index and quality of life with 7 days of preoperative tamoxifen [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-10-05.

P2-16-03: Outcomes of Nipple-Sparing Mastectomy (NSM) and Immediate Reconstruction

Background

Nipple-sparing mastectomy (NSM) is the surgical removal of breast tissue that preserves the entire skin envelope including the nipple areola skin (NAS). We report our experience performing NSMs and immediate breast reconstruction for both high-risk breast cancer treatment and prophylaxis over a six-year period at The University of Utah and Huntsman Cancer Hospital.

Methods: A retrospective chart review was performed on patients undergoing NSM from April 2005 - April 2011. Data collection included: patient demographics, oncologic details, surgical information (including reconstruction timing and type), and complications (infection, hematoma, seroma, skin necrosis, NAS complication, skin flap loss, premature expander exchange/removal, and capsular contracture).

Results: 130 patients underwent 205 NSMs. Of these, 106 (81.5%) patients received mastectomy treatment for cancer while 24 (18.5%) patients were prophylactically treated. 102 NSMs (49.8%) were on breasts with biopsy-proven cancer, while 103 (50.2%) NSMs were on breasts for prophylaxis. All patients were female with a mean age of 44.7 years (range, 16–82 years). 119 (92.2%) patients were Caucasian, 3 (2.3%) were Asian, and 1 (0.8%) was Hispanic. The mean weight was 65.2 kg (range, 42.8 - 98.8 kg) and BMI (n=106) was 23.7 kg/m2 (SE±0.4). 14 (10.9%) and 12 (9.3%) of the patients were known to have a BRCA1 and BRCA2 mutation, respectively. Two (1.6%) patients had a p53 mutation. 172 (83.5%) of the nipples were spared via an 8 cm incision lateral to the midpoint of the areola, while 5 (2.4%) of the incisions were made along the IMF. The remaining 28 (13.7%) incisions were made by other techniques. 201 (98.0%) breasts were immediately reconstructed with tissue expanders (193 went on to implant reconstruction and 8 underwent autologous tissue reconstruction). 4 (2.0%) breasts received delayed reconstruction. Positive margins were found in 15 (7.3%) of 205 breasts. 60 (58.8%) of 102 cancerous breasts that underwent NSM were Stage 0-I, 35 (34.3%) were Stage II and the remaining 8 (7.8%) were Stage III - IV. Complications by case (Table 1) and by breast (Table 2) are shown below.