Colorectal cancer

$\textit {Background:}$ Colorec tal cancer (CRC ) is the second most common t ype of cancer in the Western world. The treatment of this disease has evolved greatly, particularly for patients with metastatic disease. The advent of combination chemotherapy plus targeted agents has led to more curative resections and improved survival rates in these patients. A deeper understanding of the mechanisms of tumorigenesis has facilitated tumor characterization, prognosis and patient stratification, bringing us one step closer towards personalized medicine. $\textit {Summary:}$ There are two main pathways of CRC development: (1) chromosomal instability, also known as the classical adenoma-carcinoma sequence, and (2) microsatellite instability, caused by a defective mismatch repair (dMMR) system. Analysis of these pathways has uncovered key prognostic and predictive biomarkers to guide patient selection and treatment strategy. This review summarizes the current treatment regimens and recent advances in the personalized therapy of CRC. $\textit {Key Message:}$ Understanding of the mechanisms of CRC pathogenesis has led to new developments in tumor characterization, patient stratification, prognosis and treatment, bringing us closer to personalized therapy. $\textit {Practical Implications:}$ In the adjuvant setting, the treatment decision is driven by clinical and histopathological factors. dMMR status is one of the most robust positive prognostic factors in resected colon cancer. More and more guidelines recommend refraining from adjuvant chemotherapy in patients with dMMR. In the metastatic setting, the introduction of effective compounds, including agents that target the epidermal growth factor receptor and vascular endothelial growth factor pathways, has significantly improved survival. The presence of wild-type KRAS and NRAS (all RAS) is a positive predictive factor for epidermal growth factor receptor antibody treatment. Therefore, analysis of all RAS status is recommended for all patients with metastatic disease prior to the initiation of first-line chemotherapy

Treatment recommendations within the leeway of clinical guidelines

$\textbf {Background:}$ Recommending the optimal treatment for an individual patient requires a well-balanced consideration of various medical, social and ethical factors. The interplay of these factors, interpretation of the patient’s situation and understanding of the existing clinical guidelines can lead to divergent therapy recommendations, depending on the attending physician. Gaining a better understanding of the individual process of medical decision-making and the differences occurring will support the delivery of optimal individualized care within the clinical setting. $\textbf {Methods:}$ A case vignette of a 64-year-old patient with locally advanced pancreatic adenocarcinoma was discussed with oncologists in 14 qualitative, semi-structured interviews at two academic institutions. Relevant factors that emerged were ranked by the participants using the Q card sorting method. Qualitative data analysis and descriptive statistics were performed. $\textbf {Results:}$ Oncologists recommend different therapeutic approaches within the leeway of the relevant clinical guidelines. One group of participants endorses a rather aggressive and potentially curative approach with a combination chemotherapy following the FOLFIRINOX protocol to provide the patient with the best chances of resectability. The second group suggests a milder chemotherapy approach with gemcitabine, highlighting the palliative approach and the patient’s quality of life. Clinical guidelines are generally seen as an important point of reference, but are complicated to apply in highly individual cases. $\textbf {Conclusion:}$ The physician’s individual assessment of factors, such as biological age, general condition or prognosis, plays a decisive role in treatment recommendations, particularly in those cases which are not fully covered by guidelines. Judgment and discretion remain crucial in clinical decision-making and cannot and should not be fully ruled out by evidence-based guidelines. Therefore, a more comprehensive reflection on the interaction between evidence-based medicine and the physician’s estimation of each individual case is desirable. Knowledge of existing barriers can enhance the implementation of guidelines, for example, through medical education

Pathologic complete response of pancreatic cancer following neoadjuvant FOLFIRINOX treatment in hepatic metastasized pancreatic cancer

$\textit {Introduction:}$ Pancreatic cancer is a lethal disease and often asymptomatic. Therefore, it is most often diagnosed at an advanced stage. The standard approach in a metastasized tumor stage is palliative chemotherapy. However, the prognosis remains extremely poor. $\textit {Case Report:}$ We present the case of a patient who was diagnosed with a cancer of the head of the pancreas with hepatic metastases. After receiving palliative intended chemotherapy with the FOLFIRINOX regimen, staging computed tomography revealed the disappearance of the liver metastases and local resectability of the pancreatic head tumor. The patient underwent an uneventful Whipple's procedure. Surprisingly, pathohistological investigation revealed a complete pathological response. $\textit {Conclusion:}$ Pathological complete response after FOLFIRINOX treatment in hepatic metastasized pancreatic cancer is extremely rare. It enables surgical resection and increases the survival rate significantly

Low serological prevalence of SARS-CoV-2 antibodies in cancer patients at a German University Oncology Center

$\bf Background:$ Coronavirus disease 2019 (COVID-19) cases in Germany, as in most other places in Europe or worldwide, are still highly prevalent. Vaccination rates currently remain low, putting cancer patients at a continued risk of infection with SARS-CoV-2, while prevalence of SARS-CoV-2 antibodies among cancer patients in Germany remains essentially unknown. $\bf Methods:$ Between August 2020 and February 2021, patients admitted to our hospital were prospectively enrolled in our COVID-19 biobank. Collected sera were analyzed for SARS-CoV-2-IgM/IgG using Elecsys Anti-SARS-CoV-2 assay. $\bf Results:$ One hundred and ten patients with cancer were included in this study. With 71 (65%) patients, most had active cancer treatment, mainly chemotherapy (56%). The most frequent diagnosis was gastrointestinal cancer (54%) with pancreatic cancer being the most common cancer type (24%). Hematologic malignancies were present in 21 patients (17%). Among the cancer patients first diagnosed during the pandemic, the rate of palliative treatment situations tended to be higher (76% vs. 67%, $\it p$ = 0.17). A history of SARS-CoV-2 infection was documented in 15 (14%) patients; however, SARS-CoV-2 antibodies were detected in 10 (67%) patients only. Of the patients without a history of SARS-CoV-2 infection, none displayed SARS-CoV-2 antibodies. $\bf Conclusion:$ In the present single-center experience, a low serological prevalence of SARS-CoV-2 antibodies among cancer patients even after SARS-CoV-2 infection was found. The results support continued strict preventive measures as well as efforts toward faster vaccination, due to a low immunity level in the population

Microsatellite instability (MSI-H) is associated with a high immunoscore but not with PD-L1 expression or increased survival in patients (pts.) with metastatic colorectal cancer (mCRC) treated with oxaliplatin (ox) and fluoropyrimidine (FP) with and without bevacizumab (bev)

$\bf Introduction$ In a retrospective analysis of two randomized phase III trials in mCRC patients treated first line with oxaliplatin, fluoropyrimidine with and without Bevacizumab (the AIO KRK 0207 and R091 trials) we evaluated the association of high microsatellite instability (MSI-H), immunoscore (IS) and PD-L1 expression in relation to overall survival (OS). $\bf Methods$ In total, 550 samples were analysed. Immunohistochemical analysis of the MMR proteins and additionally fragment length analysis was performed, molecular examinations via allele-discriminating PCR in combination with DNA sequencing. Furthermore PD-L1 and IS were assessed. $\bf Results$ MSI-H tumors were more frequent in right sided tumors (13.66% vs. 4.14%) and were correlated with mutant BRAF ($\it p$ = 0.0032), but not with KRAS nor NRAS mutations (MT). 3.1% samples were found to be PD-L1 positive, there was no correlation of PDL1 expression with MSI-H status, but in a subgroup analysis of MSI-H tumors the percentage of PD-L1 positive tumors was higher than in MSS tumors (9.75% vs. 2.55%). 8.5% of samples showed a positive IS, MSI-H was associated with a high IS. The mean IS of the pooled population was 0.57 (SD 0.97), while the IS of MSI-H tumors was significantly higher (mean of 2.4; SD 1.4; $\it p$ =< 0.0001). $\bf Discussion$ Regarding OS in correlation with MSI-H, PD-L1 and IS status we did not find a significant difference. However, PD-L1 positive mCRC tended to exhibit a longer OS compared to PD-L1 negative cancers (28.9 vs. 22.1 months)

Immune response in ofatumumab treated multiple sclerosis patients after SARS-CoV-2 vaccination

$\bf Objective:$ The pandemic induced by SARS-CoV-2 has huge implications for patients with immunosuppression that is caused by disorders or specific treatments. Especially approaches targeting B cells $\it via$ anti-CD20 therapy are associated with impaired humoral immune response but sustained cellular immunity. Ofatumumab is a human anti-CD20 directed antibody applied in low dosages subcutaneously, recently licensed for Multiple Sclerosis (MS). Effects of early ofatumumab treatment on alterations of immune cell composition and immune response towards SARS-CoV-2 are incompletely understood. $\bf Methods:$ We here investigated immune cell alterations in early ofatumumab (Ofa) treated patients and effects on humoral (titer, neutralization capacity against wild type, Delta and Omicron) and cellular immune responses in Ofa treated MS patients following a third vaccination against SARS-CoV-2 compared to healthy controls. $\bf Results:$ We show that a mean treatment duration of three months in the Ofa group led to near complete B cell depletion in line with altered composition of certain $CD4^{+}$ T cell subpopulations such as enhanced frequencies of naive and a decrease of non-suppressive regulatory T cells (Tregs). Titer and neutralization capacity against SARS-CoV-2 variants was impaired while cellular immune response was sustained, characterized by a strong T helper 1 profile (Th1). $\bf Interpretation:$ In summary, low dosage ofatumumab treatment elicits sustained depletion of B cells in line with alterations of immune cells, mainly Tregs. This is associated with impaired humoral immune response towards SARS-CoV-2 vaccination but preserved, Th1 driven cellular immunity adding crucial information regarding early effects of low dosage anti-CD20 therapy on humoral and cellular immunity

Dihydropyrimidine dehydrogenase testing prior to treatment with 5-Fluorouracil, Capecitabine, and Tegafur

$\bf Background:$ 5-Fluorouracil (FU) is one of the most commonly used cytostatic drugs in the systemic treatment of cancer. Treatment with FU may cause severe or life-threatening side effects and the treatment-related mortality rate is 0.2–1.0%. $\bf Summary:$ Among other risk factors associated with increased toxicity, a genetic deficiency in dihydropyrimidine dehydrogenase (DPD), an enzyme responsible for the metabolism of FU, is well known. This is due to variants in the DPD gene (DPYD). Up to 9% of European patients carry a DPD gene variant that decreases enzyme activity, and DPD is completely lacking in approximately 0.5% of patients. Here we describe the clinical and genetic background and summarize recommendations for the genetic testing and tailoring of treatment with 5-FU derivatives. The statement was developed as a consensus statement organized by the German Society for Hematology and Medical Oncology in cooperation with 13 medical associations from Austria, Germany, and Switzerland. $\bf Key Messages:$ (i) Patients should be tested for the 4 most common genetic DPYD variants before treatment with drugs containing FU. (ii) Testing forms the basis for a differentiated, risk-adapted algorithm with recommendations for treatment with FU-containing drugs. (iii) Testing may optionally be supplemented by therapeutic drug monitoring

Impact of SARS-CoV-2 vaccination on systemic immune responses in people living with HIV

Despite the development of vaccines, which protect healthy people from severe and life-threatening Covid-19, the immunological responses of people with secondary immunodeficiencies to these vaccines remain incompletely understood. Here, we investigated the humoral and cellular immune responses elicited by mRNA-based SARS-CoV-2 vaccines in a cohort of people living with HIV (PLWH) receiving anti-retroviral therapy. While antibody responses in PLWH increased progressively after each vaccination, they were significantly reduced compared to the HIV-negative control group. This was particularly noteworthy for the Delta and Omicron variants. In contrast, CD4+ Th cell responses exhibited a vaccination-dependent increase, which was comparable in both groups. Interestingly, CD4+ T cell activation negatively correlated with the CD4 to CD8 ratio, indicating that low CD4+ T cell numbers do not necessarily interfere with cellular immune responses. Our data demonstrate that despite the lower CD4+ T cell counts SARS-CoV-2 vaccination results in potent cellular immune responses in PLWH. However, the reduced humoral response also provides strong evidence to consider PLWH as vulnerable group and suggests subsequent vaccinations being required to enhance their protection against COVID-19