Roberto Piciotti

Bio: Roberto Piciotti is an academic researcher from University of Milan. The author has contributed to research in topics: Medicine & Breast cancer. The author has an hindex of 2, co-authored 8 publications receiving 13 citations. Previous affiliations of Roberto Piciotti include European Institute of Oncology.

Mismatch repair-deficient hormone receptor-positive breast cancers: Biology and pathological characterization.

Abstract: The clinical outcome of patients with a diagnosis of hormone receptor (HR)+ breast cancer has improved remarkably since the arrival of endocrine therapy. Yet, resistance to standard treatments is a major clinical challenge for breast cancer specialists and a life-threatening condition for the patients. In breast cancer, mismatch repair (MMR) status assessment has been demonstrated to be clinically relevant not only in terms of screening for inherited conditions such as Lynch syndrome, but also for prognostication, selection for immunotherapy, and early identification of therapy resistance. Peculiar traits characterize the MMR biology in HR+ breast cancers compared to other cancer types. In these tumors, MMR genetic alterations are relatively rare, occurring in ~3 % of cases. On the other hand, modifications at the protein level can be observed also in the absence of gene alterations and vice versa. In HR+ breast cancers, the prognostic role of MMR deficiency has been confirmed by several studies, but its predictive value remains a matter of controversy. The characterization of MMR status in these patients is troubled by the lack of tumor-specific guidelines and/or companion diagnostic tests. For this reason, precise identification of MMR-deficient breast cancers can be problematic. A deeper understanding of the MMR biology and clinical actionability in HR+ breast cancer may light the path to effective tumor-specific diagnostic tools. For a precise MMR status profiling, the specific strengths and limitations of the available technologies should be taken into consideration. This article aims at providing a comprehensive overview of the current state of knowledge of MMR alterations in HR+ breast cancer. The available armamentarium for MMR testing in these tumors is also examined along with possible strategies for a tailored pathological characterization.

Breast Cancer with Bone Metastasis: Molecular Insights and Clinical Management.

Abstract: Despite the remarkable advances in the diagnosis and treatment of breast cancer patients, the presence or development of metastasis remains an incurable condition. Bone is one of the most frequent sites of distant dissemination and negatively impacts on patient's survival and overall frailty. The interplay between tumor cells and the bone microenvironment induces bone destruction and tumor progression. To date, the clinical management of bone metastatic breast cancer encompasses anti-tumor systemic therapies along with bone-targeting agents, aimed at slowing bone resorption to reduce the risk of skeletal-related events. However, their effect on patients' survival remains controversial. Unraveling the biology that governs the interplay between breast neoplastic cells and bone tissue would provide means for the development of new therapeutic agents. This article outlines the state-of-the art in the characterization and targeting the bone metastasis in breast cancer, focusing on the major clinical and translational studies on this clinically relevant topic.

Mismatch Repair Status Characterization in Oncologic Pathology: Taking Stock of the Real-World Possibilities

Abstract: The mismatch repair (MMR) system has a key role in supporting the DNA polymerase proofreading function and in maintaining genome stability Alterations in the MMR genes are driving events of tumorigenesis, tumor progression, and resistance to therapy These genetic scars may occur in either hereditary or sporadic settings, with different frequencies across tumor types Appropriate characterization of the MMR status is a crucial task in oncologic pathology because it allows for both the tailored clinical management of cancer patients and surveillance of individuals at risk The currently available MMR testing methods have specific strengths and weaknesses, and their application across different tumor types would require a tailored approach This article highlights the indications and challenges in MMR status assessment for molecular pathologists, focusing on the possible strategies to overcome analytical and pre-analytical issues

Early Breast Cancers During Pregnancy Treated With Breast-Conserving Surgery in the First Trimester of Gestation: A Feasibility Study.

Abstract: Breast cancer is the most common malignancy occurring during gestation. In early-stage breast cancer during pregnancy (PrBC), breast-conserving surgery (BCS) with delayed RT is a rational alternative to mastectomy, for long considered the standard-of-care. Regrettably, no specific guidelines on the surgical management of these patients are available. In this study, we investigated the feasibility and safety of BCS during the first trimester of pregnancy in women with early-stage PrBC. All patients with a diagnosis of PrBC during the first trimester of pregnancy jointly managed in two PrBC-specialized Centers were included in this study. All patients underwent BCS followed by adjuvant radiotherapy to the ipsilateral breast after delivery. Histopathological features and biomarkers were first profiled on pre-surgical biopsies. The primary outcome was the isolated local recurrence (ILR). Among 168 PrBC patients, 67 (39.9%) were diagnosed during the first trimester of gestation. Of these, 30 patients (age range, 23-43 years; median=36 years; gestational age, 2-12 weeks; median=7 weeks; median follow-up time=6.5 years) met the inclusion criteria. The patients that were subjected to radical surgery (n=14) served as controls. None of the patients experienced perioperative surgical complications. No ILR were observed within three months (n=30), 1 year (n=27), and 5 years (n=18) after surgery. Among the study group, 4 (12.3%) patients experienced ILR or new carcinomas after 6-13 years, the same number (n=4) had metastatic dissemination after 3-7 years. These patients are still alive and disease-free after 14-17 years of follow-up. The rate of recurrences and metastasis in the controls were not significantly different. The findings provide evidence that BCS in the first trimester PrBC is feasible and reasonably safe for both the mother and the baby.

How to Best Exploit Immunotherapeutics in Advanced Gastric Cancer: Between Biomarkers and Novel Cell-Based Approaches

Abstract: Despite extensive research efforts, advanced gastric cancer still has a dismal prognosis with conventional treatment options. Immune checkpoint inhibitors have revolutionized the treatment landscape for many solid tumors. Amongst gastric cancer subtypes, tumors with microsatellite instability and Epstein Barr Virus positive tumors provide the strongest rationale for responding to immunotherapy. Various predictive biomarkers such as mismatch repair status, programmed death ligand 1 expression, tumor mutational burden, assessment of tumor infiltrating lymphocytes and circulating biomarkers have been evaluated. However, results have been inconsistent due to different methodologies and thresholds used. Clinical implementation therefore remains a challenge. The role of immune checkpoint inhibitors in gastric cancer is emerging with data from monotherapy in the heavily pre-treated population already available and studies in earlier disease settings with different combinatorial approaches in progress. Immune checkpoint inhibitor combinations with chemotherapy (CT), anti-angiogenics, tyrosine kinase inhibitors, anti-Her2 directed therapy, poly (ADP-ribose) polymerase inhibitors or dual checkpoint inhibitor strategies are being explored. Moreover, novel strategies including vaccines and CAR T cell therapy are also being trialed. Here we provide an update on predictive biomarkers for response to immunotherapy with an overview of their strengths and limitations. We discuss clinical trials that have been reported and trials in progress whilst providing an account of future steps needed to improve outcome in this lethal disease.

HER2 Low, Ultra-low, and Novel Complementary Biomarkers: Expanding the Spectrum of HER2 Positivity in Breast Cancer

Abstract: HER2 status in breast cancer is assessed to select patients eligible for targeted therapy with anti-HER2 therapies. According to the American Society of Clinical Oncology (ASCO) and College of American Pathologists (CAP), the HER2 test positivity is defined by protein overexpression (score 3+) at immunohistochemistry (IHC) and/or gene amplification at in situ hybridization (ISH). The introduction of novel anti-HER2 compounds, however, is changing this paradigm because some breast cancers with lower levels of protein expression (i.e. score 1+/2+ with no gene amplification) benefited from HER2 antibody-drug conjugates (ADC). Recently, a potential for HER2 targeting in HER2 “ultra-low” (i.e. score 0 with incomplete and faint staining in ≤10% of tumor cells) and MutL-deficient estrogen receptor (estrogen receptor)-positive/HER2-negative breast cancers has been highlighted. All these novel findings are transforming the traditional dichotomy of HER2 status and have dramatically raised the expectations in this field. Still, a more aware HER2 status assessment coupled with the comprehensive characterization of the clinical and molecular features of these tumors is required. Here, we seek to provide an overview of the current state of HER2 targeting in breast cancers beyond the canonical HER2 positivity and to discuss the practical implications for pathologists and oncologists.

Evaluation of Micro Satellite Instability and Mismatch Repair Status in Different Solid Tumors: A Multicenter Analysis in a Real World Setting.

Abstract: Immune-checkpoint inhibitors (ICIs) play a key role in the treatment of advanced stage colorectal cancer (CRC) patients featuring a deficient DNA mismatch repair (dMMR) system or a high microsatellite instability (MSI-H) profile. However, beyond the established role in CRC patients, ICIs have highly proven efficacy in other solid tumors featuring MSI-H/dMMR status represented by endometrial, gastric, ovarian, prostatic, and pancreatic carcinomas (EC, GC, OC, PrC, and PaC). Our aim was to compare the concordance rates among the Idylla™ MSI test, TapeStation 4200, and immunohistochemical (IHC) analysis in assessing MSI-H/dMMR status in EC, GC, OC, PrC, and PaC patients. The Sanger sequencing-based Titano MSI test was used in discordant cases. One hundred and eighty-five cases (n = 40 PrC, n = 39 GC, n = 38 OC, n = 35 PaC, and n = 33 EC) were retrospectively selected. MMR protein expression was evaluated by IHC. After DNA quality and quantity evaluations, the IdyllaTM and TapeStation 4200 platforms were adopted for the evaluation of MSI status. Remarkably, compared to IHC, the Idylla™ platform achieved a global concordance rate of 94.5% (154/163) for the microsatellite stable (MSS)/proficient MMR (pMMR) cases and 77.3% (17/22) for the MSI-H/dMMR cases. Similarly, a global concordance rate of 91.4% (149/163) and 68.2% (15/22) for MSS/pMMR and MSI-H/dMMR cases was also identified between IHC and the TapeStation 4200 microfluidic system. In addition, a global concordance of 93.1% (148/159) and 69.2% (18/26) for MSS/pMMR and MSI-H/dMMR cases was observed between the Idylla™ and TapeStation 4200 platforms. Discordant cases were analyzed using the Titano MSI kit. Overall, our data pinpointed a central role for molecular techniques in the diagnostic evaluation of dMMR/MSI-H status not only in CRC patients but also in other types of solid tumors.

Mismatch repair-deficient hormone receptor-positive breast cancers: Biology and pathological characterization.

Abstract: The clinical outcome of patients with a diagnosis of hormone receptor (HR)+ breast cancer has improved remarkably since the arrival of endocrine therapy. Yet, resistance to standard treatments is a major clinical challenge for breast cancer specialists and a life-threatening condition for the patients. In breast cancer, mismatch repair (MMR) status assessment has been demonstrated to be clinically relevant not only in terms of screening for inherited conditions such as Lynch syndrome, but also for prognostication, selection for immunotherapy, and early identification of therapy resistance. Peculiar traits characterize the MMR biology in HR+ breast cancers compared to other cancer types. In these tumors, MMR genetic alterations are relatively rare, occurring in ~3 % of cases. On the other hand, modifications at the protein level can be observed also in the absence of gene alterations and vice versa. In HR+ breast cancers, the prognostic role of MMR deficiency has been confirmed by several studies, but its predictive value remains a matter of controversy. The characterization of MMR status in these patients is troubled by the lack of tumor-specific guidelines and/or companion diagnostic tests. For this reason, precise identification of MMR-deficient breast cancers can be problematic. A deeper understanding of the MMR biology and clinical actionability in HR+ breast cancer may light the path to effective tumor-specific diagnostic tools. For a precise MMR status profiling, the specific strengths and limitations of the available technologies should be taken into consideration. This article aims at providing a comprehensive overview of the current state of knowledge of MMR alterations in HR+ breast cancer. The available armamentarium for MMR testing in these tumors is also examined along with possible strategies for a tailored pathological characterization.

Breast Cancer with Bone Metastasis: Molecular Insights and Clinical Management.

Abstract: Despite the remarkable advances in the diagnosis and treatment of breast cancer patients, the presence or development of metastasis remains an incurable condition. Bone is one of the most frequent sites of distant dissemination and negatively impacts on patient's survival and overall frailty. The interplay between tumor cells and the bone microenvironment induces bone destruction and tumor progression. To date, the clinical management of bone metastatic breast cancer encompasses anti-tumor systemic therapies along with bone-targeting agents, aimed at slowing bone resorption to reduce the risk of skeletal-related events. However, their effect on patients' survival remains controversial. Unraveling the biology that governs the interplay between breast neoplastic cells and bone tissue would provide means for the development of new therapeutic agents. This article outlines the state-of-the art in the characterization and targeting the bone metastasis in breast cancer, focusing on the major clinical and translational studies on this clinically relevant topic.

The m6A/m5C/m1A Regulated Gene Signature Predicts the Prognosis and Correlates With the Immune Status of Hepatocellular Carcinoma

Abstract: RNA modification of m6A/m5C/m1A contributes to the occurrence and development of cancer. Consequently, this study aimed to investigate the functions of m6A/m5C/m1A regulated genes in the prognosis and immune microenvironment of hepatocellular carcinoma (HCC). The expression levels of 45 m6A/m5C/m1A regulated genes in HCC tissues were determined. The functional mechanisms and protein–protein interaction network of m6A/m5C/m1A regulated genes were investigated. The Cancer Genome Atlas (TCGA) HCC gene set was categorized based on 45 m6A/m5C/m1A regulated genes, and survival analysis was used to determine the relationship between the overall survival of HCC patients in subgroups. Cox and least absolute shrinkage and selection operator (LASSO) regression analyses were used to construct the risk model and nomogram for m6A/m5C/m1A regulated genes. The relationships between m6A/m5C/m1A regulated gene subsets and risk model and immune cell infiltration were analyzed using CIBERSORT. m6A/m5C/m1A regulated genes were involved in mRNA and RNA modifications, mRNA and RNA methylation, mRNA and RNA stability, and other processes. There was a statistically significant difference between cluster1 and cluster2 groups of genes regulated by m6A/m5C/m1A. The prognosis of cluster1 patients was significantly better than that of cluster2 patients. There were statistically significant differences between the two cluster groups in terms of fustat status, grade, clinical stage, and T stage of HCC patients. The risk model comprised the overexpression of YBX1, ZC3H13, YTHDF1, TRMT10C, YTHDF2, RRP8, TRMT6, LRPPRC, and IGF2BP3, which contributed to the poor prognosis of HCC patients. The high-risk score was associated with prognosis, fustat status, grade, clinical stage, T stage, and M stage and was an independent risk factor for poor prognosis in HCC patients. High-risk score mechanisms included spliceosome, RNA degradation, and DNA replication, among others, and high-risk was closely related to stromal score, CD4 memory resting T cells, M0 macrophages, M1 macrophages, resting mast cells, CD4 memory activated T cells, and follicular helper T cells. In conclusion, the cluster subgroup and risk model of m6A/m5C/m1A regulated genes were associated with the poor prognosis and immune microenvironment in HCC and are expected to be the new tools for assessing the prognosis of HCC patients.