Steadman, Jessica A.

ABSTRACT Background and Objectives Neoadjuvant chemoimmunotherapy (NACI) for node‐positive breast cancer may induce immune cell activation in regional lymph nodes (LN), confounding post‐NACI imaging. Here we evaluated RECIST 1.1 criteria to predict post‐NACI pathologic LN status. Methods We studied patients with biopsy‐proven cN+ non‐distant metastatic breast cancer receiving NACI operated on 03/2020–09/2024 with both pre‐ and post‐NACI cross‐sectional imaging. Per RECIST 1.1, LN short axis diameter (SAD) was measured in target (defined as SAD ≥ 15 mm) and nontarget (SAD 10–14.9 mm) LNs. Groups were compared using Fisher′s exact test. Results 75 patients, median age 53 years, were studied: 61% cN1, 12% cN2, and 27% cN3. Baseline median number of imaging‐suspicious LN was 4 (IQR 2‐5). Post‐NACI, 64% had a nodal pathologic complete response (pCR/ypN0). 55% met RECIST 1.1 LN assessment criteria. 21 of 32 (66%) with an imaging CR (iCR) were ypN0, while 8 of 9 (89%) without an iCR were ypN0. Neither target ( p = 0.24) nor combined target/nontarget LN iCR ( p = 0.76) predicted ypN status. Nodal pCR rates were higher in those with ≤ 1 versus > 1 suspicious LN post‐NACI (71% vs. 42%, p = 0.03). Conclusions RECIST 1.1 criteria did not predict nodal pCR for NACI‐treated node‐positive breast cancer patients. Other post‐NACI imaging assessment strategies are needed.

AbstractBackgroundProton pump inhibitors (PPIs) negatively impact fluoropyrimidine‐based chemotherapy efficacy in colorectal cancer. This study assessed PPI impact on major pathologic response (mPR) rates of pancreatic adenocarcinoma (PDAC) patients receiving fluoropyrimidine‐based chemotherapy.MethodsAn institutional retrospective review of resected PDAC patients receiving neoadjuvant fluoropyrimidine‐based chemotherapy (98% FOLFIRINOX) from 2011 to 2021 was conducted. Outcomes were stratified by use or nonuse of PPIs within 6 months of neoadjuvant chemotherapy initiation. Primary outcome was mPR defined as complete or near complete response.ResultsAmong 540 patients included, the median age was 64 (IQR: 60–70) years, 297 (55%) were male, and 202 (37%) were PPI users. 170 (31%) patients had mPR with similar rates among PPI users and nonusers (29% vs. 33%, p = 0.38). No difference in mPR was seen between PPI users and nonusers receiving chemoradiation (35% vs. 36%, p = 0.89) or ≥8 cycles of NAC (33% vs. 36%, p = 0.55). Median OS for PPI users was 30.9 versus 31.7 months for nonusers (p = 0.62). On multivariable analysis, PPI therapy was not associated with decreased survival.ConclusionPPI usage did not significantly influence mPR or OS following neoadjuvant fluoropyrimidine‐based chemotherapy in resected PDAC patients. Further analysis of all patients, not just those who underwent resection, is required.

AbstractAmong inflammatory breast cancer (IBC) patients, over one‐third have HER2‐overexpressing (HER2+) tumors. Pathologic complete response (pCR) rates to neoadjuvant targeted and chemotherapy for patients with HER2+ non‐metastatic IBC now apporach 60% and favorable long‐term survival rates are being reported for those with a pCR. Immune mechanisms contributing to this phenomenon include antibody‐mediated immune activation and induction of memory T‐cell reponses which may explain the sustained antitumor response seen after discontinuation of targeted therapies.

AbstractIntroductionMelanoma guidelines stem largely from data on non‐Hispanic White (NHW) patients. We aimed to identify features of melanoma within non‐Hispanic Black (NHB) patients to inform strategies for earlier detection and treatment.MethodsFrom 2004 to 2019 Surveillance, Epidemiology, and End Results (SEER) data, we identified nonmetastatic melanoma patients with known TN category and race. Kaplan–Meier cancer‐specific survival (CSS) estimates and multivariable Cox proportional hazard modeling analyses were performed.ResultsOf 492 597 patients, 1499 (0.3%) were NHB, who were younger (21% vs. 17% age <50) and more commonly female (54% vs. 41%) than NHW, both p < 0.0005. For NHBs, lower extremity was the most common site (52% vs. 15% for NHWs, p < 0.0001), T category was higher (55% Tis–T1 vs. 82%; 27% T3–T4 vs. 8%, p < 0.0001) and stage at presentation was higher (19% Stage III, vs. 6%, p < 0.0001). Within the NHB cohort, males were older, and more often node‐positive than females. Five‐year Stage III CSS was 42% for NHB males versus 71% for females, adjusting for age and clinical nodal status (hazard ratio 2.48).ConclusionsNHB melanoma patients presented with distinct tumor characteristics. NHB males with Stage III disease had inferior CSS. Focus on this high‐risk patient cohort to promote earlier detection and treatment may improve outcomes.

Malignant peritoneal mesothelioma (MPeM) is a rare malignancy and represents 5% to 30% of malignant mesothelioma cases. The primary curative therapy for MPeM is radical cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), with the strongest predictor of long-term survival being complete cytoreduction. There is a paucity of high-quality evidence available to guide management in MPeM; however, NCCN Guidelines for the management of MPeM were updated this year. In well-selected patients, 5-year overall survival exceeds 65%, but achieving optimal results requires careful preoperative evaluation and expert surgical management. Preoperative patient selection includes histology review and staging with cross-sectional imaging. Ideal candidates for curative intent surgery are those with epithelioid MPeM, a low peritoneal cancer index, and a good performance status. Contraindications to curative intent surgery include the sarcomatoid MPeM, distant metastases, extensive nodal metastases, and extensive small bowel serosal or mesentery involvement not amenable to complete cytoreduction. Those with biphasic histology, bicavitary disease, and metastatic lymphadenopathy may be considered for surgery following response to neoadjuvant therapy. CRS involves resection of all peritoneal disease, the extent of which varies case by case. Key aspects involve careful evaluation of all peritoneal surfaces, complete parietal peritonectomy and omentectomy, and evaluating suspicious abdominal lymph node basins. Once maximum cytoreduction is achieved, HIPEC is performed using a platinum-based perfusate. Postoperative protocols are recommended to optimize recovery and mitigate HIPEC-specific complications, namely chemotherapy-mediated nephrotoxicity and bone marrow suppression.