Role of Modern Immunotherapy in Gastrointestinal Malignancies: A Review of Current Clinical Progress

Gastrointestinal (GI) cancers are a group of highly aggressive malignancies with a huge disease burden worldwide. There is clearly a significant unmet need for new drugs and therapies to further improve the treatment outcomes of GI malignancies. Immunotherapy is a novel treatment strategy that is emerging as an effective and promising treatment option against several types of cancers. CTLA-4 and PD-1 are critical immune checkpoint molecules that negatively regulate T cell activation via distinct mechanisms. Immune checkpoint blockade with antibodies directed against these pathways has already shown clinical efficacy that has led to their FDA approval in the treatment of several solid tumors including melanoma, non-small cell lung cancer, renal cell carcinoma, urothelial carcinoma, and head and neck cancer. This review will summarize the current clinical progress of modern immunotherapy in the field of GI tumors, with a special focus on immune checkpoint blockade

A Case Report of Metastatic Castration-Resistant Prostate Cancer Harboring a \u3ci\u3ePTEN\u3c/i\u3e Loss

The treatment landscape of metastatic castration-resistant prostate cancer (mCRPC) has dramatically improved over the last decade; however, patients with visceral metastases are still faced with poor outcomes. Phosphatase and tensin homolog (PTEN) loss is observed in 40%–60% of mCRPC patients and is also associated with a poor prognosis. Several PI3K/AKT/mTOR pathway inhibitors have been studied, with disappointing anti-tumor activity. Here, we present a case of a patient with heavily treated mCRPC who had a modest tumor response to concurrent carboplatin, abiraterone acetate/prednisone, and liver-directed radiation therapy. We discuss the potential rationale supporting the use of this combination therapy and its safety in mCRPC. While the underlying basic mechanism of our patient’s anti-tumor response remains uncertain, we suggest that further prospective studies are warranted to evaluate whether this combination therapy is effective in this population of patients with pre-treated mCRPC and PTEN loss

Androgen Receptor Signaling in Prostate Cancer and Therapeutic Strategies

Understanding of the molecular mechanisms of prostate cancer has led to development of therapeutic strategies targeting androgen receptor (AR). These androgen-receptor signaling inhibitors (ARSI) include androgen synthesis inhibitor-abiraterone and androgen receptor antagonists-enzalutamide, apalutamide, and darolutamide. Although these medications provide significant improvement in survival among men with prostate cancer, drug resistance develops in nearly all patients with time. This could be through androgen-dependent or androgen-independent mechanisms. Even weaker signals and non-canonical steroid ligands can activate AR in the presence of truncated AR-splice variants, AR overexpression, or activating mutations in AR. AR splice variant, AR-V7 is the most studied among these and is not targeted by available ARSIs. Non-androgen receptor dependent resistance mechanisms are mediated by activation of an alternative signaling pathway when AR is inhibited. DNA repair pathway, PI3K/AKT/mTOR pathway, BRAF-MAPK and Wnt signaling pathway and activation by glucocorticoid receptors can restore downstream signaling in prostate cancer by alternative proteins. Multiple clinical trials are underway exploring therapeutic strategies to overcome these resistance mechanisms

Disparities in Prostate Cancer Survival in Appalachian Kentucky: A Population-Based Study

Introduction: Prostate cancer (PC) is the most common male cancer in the USA. When comparing the incidence and mortality rates of PC, the Surveillance Epidemiology and End Results data of 2005–2014 show that Appalachian Kentucky had a lower incidence (113/100 000 v 137/100 000) but a higher mortality rate (23.8% v 21.8%) when compared to non-Appalachian Kentucky. The aim of this study was to further characterize the survival disparities of PC between Appalachian and non-Appalachian Kentucky. Methods: All stages of PC patients diagnosed between 2007 and 2011 were collected through the Kentucky Cancer Registry. Baseline characteristics and survival outcomes were compared between Appalachian Kentucky and non-Appalachian Kentucky, using Pearson χ2 and Cox regression analyses in this population-based analysis. Results: Of 12 871 patients studied, 3482 (26.8%) were from Appalachian Kentucky whereas 8489 (73.2%) were from non-Appalachian Kentucky. Caucasians predominated in both groups. Most Appalachian Kentucky patients were aged 65–74 years. Appalachian Kentucky patients had a higher Gleason score, higher prostate specific antigen (PSA), more aggressive histologic grade, more distant disease, higher comorbidity score, lower education, and higher poverty compared to patients from non-Appalachian Kentucky. There was a 5-year survival difference between Appalachian Kentucky and non-Appalachian Kentucky in unadjusted analysis (p \u3c 0.001) that disappeared after adjusting with Cox regression analysis (p = 0.4). However, worsened survival was still seen with higher Gleason score, higher PSA, distant stage disease, higher Charlson comorbidity index, and very low high school education (p \u3c 0.001). Conclusion: In this population-based analysis, this study shows a significant difference in PC survival between Appalachian and non-Appalachian Kentucky. The difference was not related to geographic location, but rather to high comorbidity score, high poverty rate, and low education. Additional research is needed to understand the healthcare restraints for Appalachian Kentucky

Radiopharmaceutical Validation for Clinical Use

Radiopharmaceuticals are reemerging as attractive anticancer agents, but there are no universally adopted guidelines or standardized procedures for evaluating agent validity before early-phase trial implementation. To validate a radiopharmaceutical, it is desirous for the radiopharmaceutical to be specific, selective, and deliverable against tumors of a given, molecularly defined cancer for which it is intended to treat. In this article, we discuss four levels of evidence—target antigen immunohistochemistry, in vitro and in vivo preclinical experiments, animal biodistribution and dosimetry studies, and first-in-human microdose biodistribution studies—that might be used to justify oncology therapeutic radiopharmaceuticals in a drug-development sequence involving early-phase trials. We discuss common practices for validating radiopharmaceuticals for clinical use, everyday pitfalls, and commonplace operationalizing steps for radiopharmaceutical early-phase trials. We anticipate in the near-term that radiopharmaceutical trials will become a larger proportion of the National Cancer Institute Cancer Therapy Evaluation Program (CTEP) portfolio

Capecitabine and Temozolomide in Neuroendocrine Tumor of Unknown Primary

Incidence of low grade well-differentiated neuroendocrine tumors (NET) is on the rise. The North American Neuroendocrine Tumor Society estimates that the United States has more than 150,000 gastroenteropancreatic NET patients. About 10% of metastatic NETs can be unknown primary, and due to their rarity, dedicated treatment algorithms and regimens are not defined. Combination of capecitabine and temozolomide (CAPTEM) is one of the systemic treatments used in gastroenteropancreatic NETs. We explored clinical activity of CAPTEM in NET of unknown primary. Methods. Retrospective review of NET of unknown primary managed at the University of Kentucky over the past five years (2012–2016). Result. 56 patients with NET of unknown primary were identified; 12 patients were treated with CAPTEM. Median progression-free survival on CAPTEM in grade II and grade III NET of unknown primary was 10.8 and 7 months, respectively. Six patients showed reduction in metastatic tumor volume at three-month CT scan. Three patients had stable disease and three patients showed disease progression at the first surveillance scan. Common side-effects were as follows: four patients developed grade II thrombocytopenia, three patients developed grade I lymphocytopenia, and two patients developed hand foot syndrome (grades I and III). Six patients developed grade I fatigue. Conclusion. CAPTEM should be considered for grades I and II NET of unknown primary, especially in the case of visceral crisis or bulky disease

Evaluation of Glutaminase Expression in Prostate Adenocarcinoma and Correlation with Clinicopathologic Parameters

High Glutaminase (GLS1) expression may have prognostic implications in colorectal and breast cancers; however, high quality data for expression in prostate cancer (PCa) are lacking. The purpose of this study is to investigate the status of GLS1 expression in PCa and correlated expression levels with clinicopathologic parameters. This study was conducted in two phases: an exploratory cohort analyzing RNA-Seq data for GLS1 from The Cancer Genome Atlas (TCGA) data portal (246 PCa samples) and a GLS1 immunohistochemical protein expression cohort utilizing a tissue microarray (TMA) (154 PCa samples; 41 benign samples) for correlation with clinicopathologic parameters. In the TCGA cohort, GLS1 mRNA expression did not show a statistically significant difference in disease-free survival (DFS) but did show a small significant difference in overall survival (OS). In the TMA cohort, there was no correlation between GLS1 expression and stage, Gleason score, DFS and OS. GLS1 expression did not significantly correlate with the clinical outcomes measured; however, GLS1 expression was higher in PCa cells compared to benign epithelium. Future studies are warranted to evaluate expression levels in greater numbers of high-grade and advanced PCa samples to investigate whether there is a rational basis for GLS1 targeted therapy in a subset of patients with prostate cancer

The Role of Anticoagulation in Tumor Thrombus Associated with Renal Cell Carcinoma: A Literature Review

Tumor thrombus (TT) is a complication of renal cell carcinoma (RCC) for which favorable medical management remains undefined. While radical nephrectomy has been shown to increase overall survival in RCC patients, surgical interventions such as cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA) utilized to perform TT resection carry high mortality rates. While it has been documented that RCC with TT is associated with venous thromboembolism (VTE) development, anticoagulation use in these patients remains controversial in clinical practice. Whether anticoagulation is associated with improved survival outcomes remains unclear. Furthermore, if anticoagulation is initiated, there is limited evidence for whether direct oral anticoagulants (DOACs), heparin, or warfarin serve as the most advantageous choice. While the combination of immunotherapy and tyrosine kinase inhibitors (TKIs) has been shown to improve the outcomes of RCC, the clinical benefits of this combination are not well studied prospectively in cases with TT. In this literature review, we explore the challenges of treating RCC-associated TT with special attention to anticoagulation. We provide a comprehensive overview of current surgical and medical approaches and summarize recent studies investigating anticoagulation in RCC patients undergoing surgery, targeted therapy, and/or immunotherapy. Our goal is to provide clinicians with updated clinical insight into anticoagulation for RCC-associated TT patients

Sarcoidosis mimicking metastatic thyroid cancer following radioactive iodine therapy

Introduction: Sarcoidosis is an inflammatory disease characterized by non-caseating granulomas that can be present in diverse organ systems. Sarcoidosis can be associated with malignancy, presenting either preceding, during, or after chemotherapy. We herewith report a case of sarcoidosis mimicking cancer recurrence that developed after radioactive iodine therapy for papillary thyroid cancer. Background: A 68-year-old Caucasian woman was found to have an incidental mediastinal lymph node. She underwent biopsy, which revealed sarcoidosis. There was no further treatment or evidence of recurrence over the ensuing 9 years. She was then diagnosed with low-grade papillary thyroid cancer in the right posterior lobe and treated with total thyroidectomy followed by radioactive iodine therapy. Six months later, she was found to have elevated serum thyroglobulin. Post–remnant ablation scan showed increased tracer uptake in the bed of the thyroid. Though two thyroid ultrasound scans were negative, she was treated with I-131 for possible recurrence. She then developed right hip pain, prompting further investigation. Though a skeletal survey was negative, an 18-fluorodeoxyglucose positron emission tomography (PET) scan study revealed multiple hypermetabolic skeletal lesions in both humeri and the proximal left femur. In addition, hypermetabolic hilar and mediastinal nodes were noted. As widespread cancer metastasis was suspected, bone biopsy was performed, which showed non-caseating granulomas, consistent with recurrence of sarcoidosis. Conclusion: Sarcoid lesions may mimic metastatic disease or recurrence in oncologic patients. Biopsy and histopathology examination should be performed to confirm the diagnosis. Recurrence or reactivation of sarcoidosis has been proposed to result from altered immunologic milieu because of the presence of either active cancer or its therapy. Teodorovic and colleagues postulated that the radioactive I-131 therapy leads to reduced secretion of Th2 cytokines such as interleukin (IL)-4, IL-5, and IL-13. Few case reports of sarcoidosis associated with papillary carcinoma have been published; this is the first report of systemic recurrence of sarcoidosis associated with papillary thyroid carcinoma after treatment with radioactive iodine therapy

Metaplastic breast cancer with chondroid differentiation

Background: Metaplastic carcinoma of the breast is an extremely rare subtype of breast cancer with an incidence of <1% of all breast neoplasms. Metaplastic carcinoma with chondroid differentiation is the rarest among all histologic subtypes of breast cancer. We report a case of infiltrating ductal carcinoma with metaplastic features of chondroid differentiation. Case presentation: A 58-year-old-woman presented to our clinic with a 4-month history of a lump in her right breast. On examination, a firm non-tender mass measuring 2×2 cm was noted in the right upper outer quadrant. It was not attached to the underlying structures. Mammography revealed a dense irregular mass in the axillary tail and a circumscribed nodule in the 6 O'clock periareolar region. This was a new development compared to the patient's most recent screening mammogram performed 2 years and 6 months previously. Ultrasound demonstrated a lobulated solid mass in the axillary tail and a simple cyst in the 6 O'clock periareolar region. Biopsy of the areolar region of the right breast revealed atypical duct hyperplasia. Fine needle aspiration cytology of the right breast axillary tail revealed a poorly differentiated invasive carcinoma consistent with mammary duct origin. On histopathological examination, it was an infiltrating ductal carcinoma with metaplastic features of chondroid differentiation. The tumor was estrogen receptor, progesterone receptor, and HER-2 negative with 0% nuclear staining. Ki-67 index was 52% with strong nuclear staining. The overall ELSTON grade of invasive carcinoma was grade 3. The patient received adjuvant chemotherapy with AC-T (adriamycin, cytoxan, and taxol) and is currently undergoing surveillance for recurrent disease. Conclusion: Metaplastic breast cancer is an extremely rare subtype of breast carcinoma. Initial management of localized disease consists of wide excision with clear surgical margins followed by radiation or mastectomy and sentinel lymph node biopsy. Although standard breast chemotherapy regimens such as AC-T are routinely used in metaplastic breast cancer in both adjuvant and metastatic settings, outcomes are significantly inferior to other breast subtypes. Further studies are required to explore targeted treatment to achieve better outcomes in this patient population