Expression of c-erb-B2 oncoprotein as a neoantigen strategy to repurpose anti-neu antibody therapy in a model of melanoma.

In this study, we tested a novel approach of "repurposing" a biomarker typically associated with breast cancer for use in melanoma. HER2/neu is a well characterized biomarker in breast cancer for which effective anti-HER2/neu therapies are readily available. We constructed a lentivirus encoding c-erb-B2 (the animal homolog to HER2/neu). This was used to transfect B16 melanoma in vitro for use in an orthotopic preclinical mouse model, which resulted in expression of c-erb-B2 as a neoantigen target for anti-c-erb-B2 monoclonal antibody (7.16.4). The c-erb-B2-expressing melanoma was designated B16/neu. 7.16.4 produced statistically significant in vivo anti-tumor responses against B16/neu. This effect was mediated by NK-cell antibody-dependent cell-mediated cytotoxicity. To further model human melanoma (which expresses <5% HER2/neu), our c-erb-B2 encoding lentivirus was used to inoculate naïve (wild-type) B16 tumors in vivo, resulting in successful c-erb-B2 expression. When combined with 7.16.4, anti-tumor responses were again demonstrated where approximately 40% of mice treated with c-erb-B2 lentivirus and 7.16.4 achieved complete clinical response and long-term survival. For the first time, we demonstrated a novel strategy to repurpose c-erb-B2 as a neoantigen target for melanoma. Our findings are particularly significant in the contemporary setting where newer anti-HER2/neu antibody-drug candidates have shown increased efficacy.

Liposomal Phenylephrine Nanoparticles Enhance the Antitumor Activity of Intratumoral Chemotherapy in a Preclinical Model of Melanoma.

Intratumoral injection of anticancer agents has limited efficacy and is not routinely used for most cancers. In this study, we aimed to improve the efficacy of intratumoral chemotherapy using a novel approach comprising peri-tumoral injection of sustained-release liposomal nanoparticles containing phenylephrine, which is a potent vasoconstrictor. Using a preclinical model of melanoma, we have previously shown that systemically administered (intravenous) phenylephrine could transiently shunt blood flow to the tumor at the time of drug delivery, which in turn improved antitumor responses. This approach was called dynamic control of tumor-associated vessels. Herein, we used liposomal phenylephrine nanoparticles as a "local" dynamic control strategy for the B16 melanoma. Local dynamic control was shown to increase the retention and exposure time of tumors to intratumorally injected chemotherapy (melphalan). C57BL/6 mice bearing B16 tumors were treated with intratumoral melphalan and peri-tumoral injection of sustained-release liposomal phenylephrine nanoparticles (i.e., the local dynamic control protocol). These mice had statistically significantly improved antitumor responses compared to melphalan alone (p = 0.0011), whereby 58.3% obtained long-term complete clinical response. Our novel approach of local dynamic control demonstrated significantly enhanced antitumor efficacy and is the subject of future clinical trials being designed by our group.

A Unicorn Disease: The Large Duct Variant of Invasive Ductal Adenocarcinoma of the Pancreas.

Large duct adenocarcinoma (LDA) is a rare histopathological variant of pancreatic ductal adenocarcinoma (PDAC) that closely mimics intraductal papillary mucinous neoplasm (IPMN). We present a 74-year-old female diagnosed with LDA in 2017. She was initially managed with chemotherapy and laparoscopic distal pancreatectomy. After five years of stable disease on systemic chemotherapy, she was referred to us to explore further definitive treatments. We used a multidisciplinary approach with curative-intent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC), followed by oral maintenance chemotherapy. Subsequent scans showed stable disease; she eventually underwent neoadjuvant radiation and surgery with intraoperative radiation therapy (IORT) and achieved remission.

Human intravital microscopy in the study of sarcomas: an early trial of feasibility.

Sarcomas comprise a vast and heterogenous group of rare tumors. Because of their diversity, it is challenging to study sarcomas as a whole with regard to their biological and molecular characteristics. This diverse set of tumors may also possess differences related to their tumor-associated vasculature, which in turn may impact the ability to deliver systemic therapies (e.g., chemotherapy, targeted therapies, and immunotherapy). Consequently, response to systemic treatment may also be variable as these depend on the ability of the therapy to reach the tumor target via the tumor-associated vasculature. There is a paucity of data regarding sarcoma-related tumor vessels, likely in part to the rarity and heterogeneity of this cancer as well as the previously limited ability to image tumor-associated vessels in real time. Our group has previously utilized confocal fluorescent imaging technology to observe and characterize tumor-associated vessels in real time during surgical resection of tumors, including cutaneous melanoma and carcinomatosis implants derived from gastrointestinal, gynecological, or primary peritoneal (e.g., mesothelioma) tumors. Our prior studies have demonstrated the feasibility of real-time, human intravital microscopy in the study of these tumor types, leading to early but important new data regarding tumor vessel characteristics and their potential implications on drug delivery and efficacy. In this brief report, we present our latest descriptive findings in a cohort of patients with sarcoma who underwent surgical resection and real-time, intravital microscopy of their tumors. Overall, intravital imaging was feasible during the surgical resection of large sarcomas. Clinical trial registrations: ClinicalTrials.gov, identifier NCT03517852; ClinicalTrials.gov, identifier NCT03823144.

How Well Does Non-mass Enhancement Correlate With DCIS/Invasive Cancer?

INTRODUCTION: Contiguous non-mass enhancement (NME) often coexists with a solid tumor component on MRI, but it can be challenging to predict whether NME represents invasive breast cancer, ductal carcinoma in situ (DCIS), benign disease, or biopsy site reaction. The purpose of this study was to determine the association between the size/extent of NME and the presence of invasive cancer and/or DCIS on final pathology. METHODS: This was a single institution retrospective analysis of a prospectively maintained breast cancer registry (2010-2020). Female patients who underwent surgical resection were included if they had a diagnosis of invasive breast cancer (with or without DCIS) and had an MRI showing both a solid mass and contiguous NME. The size of NME on MRI was compared with the size of invasive cancer and/or DCIS on the final pathology. RESULTS: From a total of 3443 patients, 225 patients were included. 86.2% had invasive ductal carcinoma (IDC), and 12.0% had invasive lobular carcinoma 76.9% were ER+, 16.4% were HER2+, and 13.3% were triple negative breast cancer (TNBC). 18.7% received neoadjuvant chemotherapy (NCT) of whom 31% achieved a complete radiographic/pathologic response. Pearson correlation coefficients (r) between the size of NME and invasive cancer/DCIS showed a strong and positive correlation of MRI NME with DCIS on pathology in patients without NCT. Subgroup analysis showed the strongest correlations for NME and DCIS among non-white (r = .70) and HER2 + patients (r = .74) who did not receive NCT. CONCLUSIONS: Strong correlations between NME and DCIS were found for HER2 + disease and non-white patients, but only modest correlations were found for other patient/disease characteristics. These correlations may impact decisions in surgical approach.

Liquid biopsies for colorectal cancer: a narrative review of ongoing clinical trials and the current use of this technology at a comprehensive cancer center.

Objective: In this review, we summarize ongoing clinical trials involving liquid biopsies (LB) for colorectal cancer (CRC), outlining the current landscape and the future implementation of this technology. We also describe the current use of LB in CRC treatment at our institution, the Mayo Clinic Enterprise. Background: The use of LB in CRC treatment merits close attention. Their role is being evaluated in the screening, non-intervention, intervention, and surveillance settings through many active trials. This, coupled with the technique's rapid integration into clinical practice, creates constant evolution of care. Methods: Review of ClinicalTrials.gov was performed identifying relevant and active trials involving LB for CRC. "Colorectal cancer" plus other terms including "liquid biopsies" and "ctDNA" were used as search terms, identifying 35 active trials. Conclusions: LB use for the CRC is actively being investigated and requires close attention. Based on current evidence, Mayo Clinic Enterprise currently uses LB in the non-interventional, interventional and surveillance setting, but not for screening. Results of these trials may further establish the use of LB in the management of CRC.

Management of a Primary Retroperitoneal Yolk Sac Tumor.

BACKGROUND Existing literature has detailed occurrences of retroperitoneal yolk sac tumors (YSTs) as the result of metastasis from a primary gonadal site. However, primary retroperitoneal YSTs are extremely rare, thus remaining a challenge to diagnose and treat. We present a complex case of a large primary retroperitoneal YST in a man treated with neoadjuvant chemotherapy followed by surgical resection. CASE REPORT A 31-year-old man presented with a chief symptom of severe lower abdominal pain. Diagnostic imaging revealed a large, rapidly progressing neoplasm in the retroperitoneal region, initially thought to be a sarcoma. However, the pathological results from further biopsies found the mass to be a retroperitoneal YST, which was tethered to a large portion of the small bowel. A testicular ultrasound was used to confirm that the mass was a primary tumor with no origins in the gonads. The tumor progressed to involve several fistulas connected to the small intestine and anterior abdominal wall. The patient was treated with 3 cycles of bleomycin, etoposide, and cisplatin, followed by surgical excision of the residual mass. The patient retained normal gastrointestinal functions, and subsequent imaging revealed no evidence of recurrence 2.5 years following resection. CONCLUSIONS Owing to the rarity of extragonadal primary YSTs, diagnostic and treatment standards have not yet been sufficiently explored. Our case demonstrates that a combination of chemotherapy and surgical resection should be considered for select patients with primary YST in the retroperitoneal region.

Outcomes of patients with invasive mucinous and tubular carcinomas of the breast.

Invasive tubular carcinoma (ITC) and invasive mucinous carcinoma (IMC) of the breast are rare histologic subtypes of breast cancer associated with favorable prognoses. The aim of our study was to investigate the outcomes for these rare subtypes using the National Cancer Database. Female patients diagnosed with ITC or IMC between 2005 and 2014 were analyzed. The primary outcome was overall survival (OS), and we analyzed its association with adjuvant therapy. 2735 patients with ITC and 5602 patients with IMC were identified. ITC presented in younger patients (57 vs. 67 years), had smaller tumors (size <1 cm, 63.1% vs. 25.4%), earlier stage, and less node-positive disease (5% vs. 8.6%), compared with IMC. Older age, government insurance, lower income, treatment in a community cancer program, large tumor size, positive nodal status, and without endocrine therapy were associated with worse OS with either subtype on multivariate analysis. No OS benefit was found for node-positive ITC that received adjuvant chemotherapy compared with those who did not. (5-year OS of 96.0% vs. 91.3%, p = 0.17).OS was improved for IMC that received adjuvant chemotherapy (10-year OS: 82.5% vs. 60.1%, p = 0.008) and endocrine therapy (10-year OS: 86.6% vs. 81.2%, p < 0.001). We concluded that ITC has favorable clinicopathological characteristics and prognosis, even with node-positive disease. ITC and IMC may need to be evaluated independently when administering adjuvant treatment plans.

Analysis of Differentiation Changes and Outcomes at Time of First Recurrence of Retroperitoneal Liposarcoma by Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG).

BACKGROUND: Local recurrence following resection of retroperitoneal liposarcoma (RLPS) is common. Well-differentiated (WD) and dedifferentiated (DD) RLPS are distinct entities with differing outcomes. A few reports suggest that WDLPS can recur as DDLPS and that DDLPS can recur as WDLPS. This study evaluates whether this change in differentiation from the primary tumor to the first local recurrence impacts long-term outcomes. METHODS: Retrospective review from 22 sarcoma centers identified consecutive patients who underwent resection for a first locally recurrent RLPS from January 2002 to December 2011. Outcomes measured included overall survival, local recurrence, and distant metastasis. RESULTS: A total of 421 RPLS patients were identified. Of the 230 patients with primary DDLPS, 34 (15%) presented WDLPS upon recurrence (DD → WD); and of the 191 patients with primary WDLPS, 54 (28%) presented DDLPS upon recurrence (WD → DD). The 6-year overall survival probabilities (95% CI) for DD → DD, DD → WD, WD → WD, and WD → DD were 40% (32-48%), 73% (58-92%), 76% (68-85%), and 56% (43-73%) (p < 0.001), respectively. The 6-year second local recurrence incidence was 66% (59-73%), 63% (48-82%), 66% (57-76%), and 77% (66-90%), respectively. The 6-year distant metastasis incidence was 13% (9-19%), 3% (0.4-22%), 5% (2-11%), and 4% (1-16%), respectively. On multivariable analysis, DD → WD was associated with improved overall survival when compared with DD → DD (p < 0.001). Moreover, WD → DD was associated with a higher risk of LR (p = 0.025) CONCLUSION: A change in RLPS differentiation from primary tumor to first local recurrence appears to impact survival. These findings may be useful in counseling patients on their prognosis and subsequent management.

Treatment Contraindications Based on Comorbidity Status in Patients With Melanoma in the United States.

BACKGROUND/AIM: Melanoma incidence has increased in the United States over the past few decades, and disparities in patient treatment have been described. Although most patients with melanoma are good candidates for curative treatment, some are considered poor candidates for treatment because of comorbid conditions. We examined whether patient demographics influence treatment contraindication in melanoma. PATIENTS AND METHODS: The National Cancer Database (NCDB) was used to identify patients with melanoma from 2004 through 2015. Multivariate logistic regression was used to determine independent associations, adjusted for confounders. We excluded patients who did not receive treatment for reasons and patients with unknown treatment status. RESULTS: A total of 499,092 patients met the inclusion criteria. Of these, 525 (0.1%) had Treatment contraindicated because of comorbid conditions (TCBC) and 498,567 (99.9%) received treatment. Multivariate logistic regression showed higher odds of TCBC in patients with government insurance (OR=1.34, 95%CI=03-1.73; p=0.03) and patients without insurance (OR=2.75, 95%CI=1.76-4.29; p<0.001) than patients with private insurance. CONCLUSION: Demographic disparities affects treatment decision in oncological patients. Our study demonstrated a significantly higher likelihood of "nontreatment because of comorbid conditions" among melanoma patients with government insurance or without insurance. Greater efforts are needed to address inequalities in melanoma treatment in the United States.

A pilot trial of intravital microscopy in the study of the tumor vasculature of patients with peritoneal carcinomatosis.

Aberrancies in the tumor microvasculature limit the systemic delivery of anticancer agents, which impedes tumor response. Using human intravital microscopy (HIVM), we hypothesized that HIVM would be feasible in patients with peritoneal carcinomatosis (PC). During cytoreductive surgery with hyperthermic intraperitoneal chemotherapy for PC, HIVM was performed in both tumor and non-tumor areas. The primary outcome was HIVM feasibility to measure vessel characteristics. We secondarily evaluated associations between HIVM vessel characteristics and oncologic outcomes (RECIST response to neoadjuvant therapy and disease-specific survival). Thirty patients with PC were enrolled. Nineteen patients (63.3%) received neoadjuvant therapy. HIVM was feasible in all patients. Compared to non-tumor (control) areas, PC areas had a lower density of functional vessels, higher proportion of non-functional vessels, smaller lumenal diameters, and lower blood flow velocity. Qualitative differences in these vessel characteristics were observed among patients who had partial response, stable disease, or progressive disease after receiving neoadjuvant therapy. However, no statistically significant relationships were found between HIVM vessel characteristics and oncologic outcomes. These novel findings comprise the first-in-human, real-time evidence of the microscopic differences between normal and tumor-associated vessels and form the basis for our larger, ongoing clinical trial appropriately powered to determine the clinical utility of HIVM (NCT03823144).

Morbidity and Outcomes After Distal Pancreatectomy for Primary Retroperitoneal Sarcoma: An Analysis by the Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group.

BACKGROUND: Multi-visceral resection often is used in the treatment of retroperitoneal sarcoma (RPS). The morbidity after distal pancreatectomy for primary pancreatic cancer is well-documented, but the outcomes after distal pancreatectomy for primary RPS are not. This study aimed to evaluate morbidity and oncologic outcomes after distal pancreatectomy for primary RPS. METHODS: In this study, 26 sarcoma centers that are members of the Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG) retrospectively identified consecutive patients who underwent distal pancreatectomy for primary RPS from 2008 to 2017. The outcomes measured were 90-day severe complications (Clavien-Dindo ≥ 3), postoperative pancreatic fistula (POPF) rate, and oncologic outcomes. RESULTS: Between 2008 and 2017, 280 patients underwent distal pancreatectomy for primary RPS. The median tumor size was 25 cm, and the median number of organs resected, including the pancreas, was three. In 96% of the operations, R0/R1 resection was achieved. The 90-day severe complication rate was 40 %. The grades B and C POPF complication rates were respectively 19% and 5% and not associated with worse overall survival. Administration of preoperative radiation and factors to mitigate POPF did not have an impact on the risk for the development of a POPF. The RPS invaded the pancreas in 38% of the patients, and local recurrence was doubled for the patients who had a microscopic, positive pancreas margin (hazard ratio, 2.0; p = 0.042). CONCLUSION: Distal pancreatectomy for primary RPS has acceptable morbidity and oncologic outcomes and is a reasonable approach to facilitate complete tumor resection.

Clinicopathologic Characteristics and Prognosis of Invasive Papillary Carcinoma of the Breast.

BACKGROUND: Invasive papillary carcinoma (IPC) of the breast is thought to carry a more favorable prognosis than invasive ductal carcinoma (IDC). The aim of this study is to investigate the clinicopathological characteristics between IPC and IDC and their prognosis using a large nationwide data set. METHODS: Female patients diagnosed with malignant IPC and IDC between 2005 and 2014 were analyzed. Patients with incomplete survival data, stage 0/IV, unknown stage, or recurrent disease were excluded. Five-year overall survival was compared between IPC and IDC. RESULTS: Among 308,426 patients, 1147 had IPC and 307,279 had IDC. IPC presented more in older postmenopausal women, black Americans, and people who had government insurance. IPC had larger tumor size, lower-grade, and earlier-stage disease, less node-positive disease, higher hormone positivity, and lower human epidermal growth factor receptor 2 amplification. Adjuvant radiation and chemotherapy rates were lower in IPC than those in IDC. IPC had a similar 5-year overall survival as compared with IDC overall (86.8% versus 88.7%) (P = 0.06). Age, pathologic stage, and radiation treatment were shown to be independent prognostic factors of IPC. CONCLUSIONS: IPC has a similar prognosis as IDC, suggesting that these patients should follow the same treatment protocols.

Postoperative Morbidity After Resection of Recurrent Retroperitoneal Sarcoma: A Report from the Transatlantic Australasian RPS Working Group (TARPSWG).

BACKGROUND: This study aimed to evaluate perioperative morbidity after surgery for first locally recurrent (LR1) retroperitoneal sarcoma (RPS). Data concerning the safety of resecting recurrent RPS are lacking. METHODS: Data were collected on all patients undergoing resection of RPS-LR1 at 22 Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG) centers from 2002 to 2011. Uni- and multivariable logistic models were fitted to study the association between major (Clavien-Dindo grade ≥ 3) complications and patient/surgery characteristics as well as outcome. The resected organ score, a method of standardizing the number of organs resected, as previously described by the TARPSWG, was used. RESULTS: The 681 patients in this study had a median age of 59 years, and 51.8% were female. The most common histologic subtype was de-differentiated liposarcoma (43%), the median resected organ score was 1, and 83.3% of the patients achieved an R0 or R1 resection. Major complications occurred for 16% of the patients, and the 90-day mortality rate was 0.4%. In the multivariable analysis, a transfusion requirement was found to be a significant predictor of major complications (p < 0.001) and worse overall survival (OS) (p = 0.010). However, having a major complication was not associated with a worse OS or a higher incidence of local recurrence or distant metastasis. CONCLUSIONS: A surgical approach to recurrent RPS is relatively safe and comparable with primary RPS in terms of complications and postoperative mortality when performed at specialized sarcoma centers. Because alternative effective therapies still are lacking, when indicated, resection of a recurrent RPS is a reasonable option. Every effort should be made to minimize the need for blood transfusions.