Feasibility and dynamics of preoperative circulating tumor DNA in patients with gastroesophageal cancer receiving preoperative treatment

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Background: Tumor-informed circulating tumor DNA (ctDNA) testing has shown high sensitivity and specificity for detecting molecular residual disease across solid tumors. However, the requirement of high-quality tissue specimens for upfront sequencing and designing of personalized ctDNA assays can be challenging using preoperative biopsy samples. There is a paucity of data on the feasibility of testing in preop tissue specimens in patients (pts) with gastroesophageal cancer (GEC) as well as its preop dynamics. Methods: We prospectively enrolled pts with locally advanced esophageal, gastroesophageal junctional (GEJ), or gastric cancer who were to receive preop treatment and surgery between 11/2021 and 07/2022. Tumor tissue was analyzed with next-generation sequencing to design a personalized, tumor-informed multiplex PCR assay (Signatera bespoke mPCR NGS assay) for each patient. Peripheral blood was collected for ctDNA analysis at baseline (before preoperative treatment), every 4 weeks until surgery, after surgery (before adjuvant therapy), and then every 4 weeks for patients who received adjuvant chemotherapy or every 3 months for patients who received adjuvant immunotherapy or no active treatment. Results: A total of 17 pts were enrolled, of which 7 had esophageal, 5 had GEJ, and 5 had gastric cancer. Tumor tissues from 14 (82.4%) pts passed quality control (QC), of which 11 were preoperative biopsy samples and 3 were surgically resected tissue. All 14 pts had detectable baseline ctDNA prior to preoperative treatment, with a median at 1.05 mean tumor molecules per mL of plasma (MTM/mL). Of these, 92.8% (13/14) of pts achieved ctDNA clearance by a median of 5 weeks from the start of preoperative treatment. Four pts opted for endoscopy surveillance, of whom 1 pt had transient ctDNA clearance at week 10, but had positive ctDNA at week 14, which persisted as of week 26. Conclusions: In our cohort, locally advanced GEC were ctDNA shedders. Preoperative tumor-informed ctDNA testing was feasible. Further studies to evaluate correlation between ctDNA dynamics and response to treatment are warranted. [Table: see text]

Artificial intelligence and machine learning in colorectal cancer

Colorectal cancer (CRC) is a heterogeneous illness characterized by various epigenetic and microenvironmental changes and is the third-highest cause of cancer-related death in the US. Artificial intelligence (AI) with its ability to allow automatic learning and improvement from experiences using statistical methods and Deep learning has made a distinctive contribution to the diagnosis and treatment of several cancer types. This review discusses the uses and application of AI in CRC screening using automated polyp detection assistance technologies to the development of computer-assisted diagnostic algorithms capable of accurately detecting polyps during colonoscopy and classifying them. Furthermore, we summarize the current research initiatives geared towards building computer-assisted diagnostic algorithms that aim at improving the diagnostic accuracy of benign from premalignant lesions. Considering the evolving transition to more personalized and tailored treatment strategies for CRC, the review also discusses the development of machine learning algorithms to understand responses to therapies and mechanisms of resistance as well as the future roles that AI applications may play in assisting in the treatment of CRC with the aim to improve disease outcomes. We also discuss the constraints and limitations of the use of AI systems. While the medical profession remains enthusiastic about the future of AI and machine learning, large-scale randomized clinical trials are needed to analyze AI algorithms before they can be used.

Safety of sequential immune checkpoint inhibitors after prior immune therapy

BACKGROUND

The use of immune checkpoint inhibitors (ICI) has transformed cancer treatment. Subsequent ICI use has become increasingly common following disease progression. We aim to evaluate the safety and tolerability of the sequential ICI treatment modality.

METHODS

Retrospective review of confirmed carcinoma from January 2014 to December 2018. Patients were categorized into "initial ICI arm" and "sequential ICI arm" defined as patients receiving single, dual or chemo-immunotherapy ICI following an initial ICI regimen. Primary outcome was the development of a new or recurrent immune related adverse event (irAE) during sequential therapy. Secondary outcomes were the number of cycles prior to the development of irAE and grade of irAE.

RESULTS

A total of 483 patients received ICI during the timeframe. Of those, 22 patients received sequential ICI. The diagnoses included ten lung cancer, seven melanoma, four renal cell carcinoma and one bladder cancer. 16 patients received single agent ICI following the initial ICI, three patients received dual ICI following the initial ICI, one patient received chemotherapy-immunotherapy following initial ICI, and two patients received chemo-immunotherapy after dual ICI. Four patients developed new irAE and one patient developed the same irAE on sequential treatment. A higher proportion of patients experienced grade 3 irAE in the sequential arm compared to the initial ICI arm (p = 0.03). No statistical difference was found between the development of irAE and the number of cycles prior to development of irAE in either treatment groups (p = 0.5).

CONCLUSION

Our data shows overall safety of sequencing ICI when close monitoring was employed.

Obesity diabetes and dyslipidemia as determinants of immune checkpoint inhibitors response in non-small cell lung cancer

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Background: Immune checkpoint inhibitors (ICI) are standard of care in the treatment of non-small cell lung cancer (NSCLC). Predictive markers of response to ICI are being studied extensively. Obesity has been correlated with a better response to ICI in NSCLC and other types of cancer. This may in-part be related to high circulating leptin or impaired T-cell fatty acid oxidation within the tumor microenvironment. We aim to further explore the effects of obesity, dyslipidemia and other components of the metabolic syndrome such as diabetes on treatment outcomes on NSCLC patients receiving ICI. Methods: We conducted a retrospective cohort study in patients with NSCLC treated with pembrolizumab, nivolumab, durvalumab, cemiplimab or atezolizumab as monotherapy or combined with chemotherapy at Mount Auburn and Lahey Hospital between January 2016 to June 2021. Obesity was defined as body mass index (BMI) > 30 kg/m2, dyslipidemia and type 2 diabetes were defined by ICD-10 diagnosis codes. Overall survival was evaluated. Kaplan-Meier survival analysis and cox proportional hazards regression were used to assess correlation between overall survival and obesity, dyslipidemia, type 2 diabetes, metformin use and statin use. These were adjusted for age, biological sex, cancer stage, ECOG and smoking status. Patients with BMI < 18.5 were excluded. Results: We identified 408 patients with NSCLC who were treated with ICIs. Of these, 66.7% had adenocarcinoma, 29.1% had squamous and 4.2% had either adenosquamous, large cell or poorly differentiated carcinoma. Among these patients 23.3% were classified as obese, 55.6% had dyslipidemia and 23% had type 2 diabetes. Of these, 66% of patients received ICIs as monotherapy. Median survival was 840 days in obese patients compared to 483 days in non-obese patients (HR 0.66, CI 0.42-0.92, p = 0.014). Conversely, within this cohort, median survival in patients with dyslipidemia was 483 days when compared to 762 days in controls (HR 1.37, CI 1.07-1.81, p = 0.013). Overall survival was not significantly different between type 2 diabetes, metformin use or statin use. Conclusions: Our study shows a trend towards a better survival in obesity and poor survival associated with dyslipidemia. Obesity and dyslipidemia may be important markers of ICI response in patients with NSCLC regardless of treatment strategies. Further studies are needed to explore the molecular mediators within the metabolic syndrome that may provide a synergistic effect with immune checkpoint inhibitors.

Participation of Black Americans in Cancer Clinical Trials: Current Challenges and Proposed Solutions

Low participation of Black Americans in cancer clinical trials is a well-established predicament. Many factors resulted in this current dilemma with racism being the fundamental unit. Here, we discuss some current challenges and proposed solutions to help in increasing the enrollment of Black Americans in cancer clinical trials. We suggest implementing the least acceptable race-specific percentage as a new bar that registrational clinical trials need to pass before cancer drugs approval. Clinical trials will continue to draw the future of cancer therapeutics in which we believe that a prompt improvement of Black Americans participation is warranted.

Insurance data of patients receiving sequential immune checkpoint inhibitors: A single center experience

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Background: Immune checkpoint inhibitors (ICI) up regulate T cell activity promoting tumor cell death and revolutionized modern oncology. The use and number of indications for ICI is growing at an unprecedented speed. Combination and sequential ICI therapies have been shown to be beneficial in certain types of cancer. There is no significant data to support non-FDA approved sequential use of ICI when patients develop toxicities or progression which could result in a significant financial burden on the patient and the health care system. We conducted a retrospective review of cancer patients receiving ICI at our institution and evaluated the insurance status of these patients who received sequential ICI. Methods: We retrospectively reviewed Oncology patients’ charts who received ICI between January 1, 2014 to December 18, 2018. We identified patients receiving sequential ICI, to be defined as patients who received a second ICI, following an initial ICI therapy. Insurance status was evaluated for patients receiving sequential therapy. Commercial insurance was defined as either private or non-Medicare/Medicaid. Results: Out of total 437 patients receiving ICI, 15 patients received sequential ICI. 11 patients were transitioned to a secondary ICI following disease progression (73%), three had immune related adverse events and one was switched per standard of care. Nine patients (60%) had commercial insurance and six patients (40%) had medicare/medicaid. Of those, one had urothelial carcinoma and was switched to pembrolizumab from atezolizumab due to disease progression. One patient had melanoma and received nivolumab following ipilimumab when data from the CHECKMATE 238 were published. Three patients with melanoma were transitioned from ipilimumab to nivolumab, two had disease progression and one had autoimmune dermatitis. Two patients had lung adenocarcinoma and were switched from nivolumab to pembrolizumab due to disease progression. One patient had small cell lung cancer and received pembrolizumab following nivolumab due to disease progression. One patient had squamous cell lung cancer and was switched to pembrolizumab from nivolumab following disease progression. Conclusions: With the rapid growth and advancement of ICI indications, there is limited data available on the benefits of sequential ICI to our patients in the clinical setting. We report a small percentage of oncology patients receiving sequential treatment with or without FDA approval and explore their insurance status. Majority of our patients who transitioned to a second ICI due to progression had commercial insurance. Larger prospective studies are needed to evaluate sequential ICI efficacy and tolerability and cost effectiveness.

Transplant-associated Thrombotic Microangiopathy Treated with Eculizumab and Romiplostim

Transplant-associated thrombotic microangiopathy (TA-TMA) can occur after solid organ transplantation. It results in thrombocytopenia, haemolytic anaemia and microvascular occlusion. TA-TMA is not fully understood and treatment has not been clearly established. However, there is increasing evidence to suggest an immune-complement mediated component to its development. Eculizumab is a monoclonal antibody that inhibits the cleavage of C5 into pro-inflammatory, prothrombotic terminal complement elements and has been utilized in the treatment of atypical haemolytic uremic syndrome. We report a case of TA-TMA successfully treated with eculizumab and romiplostim. This case adds to the evidence that TA-TMA is triggered by complement dysregulation and suggests possible interventions for refractory cases.

LEARNING POINTS

Transplant-associated thrombotic microangiopathy (TA-TMA) may occur in solid organ transplant patients.Eculizumab may be used for the treatment of TA-TMA.

KRAS and NRAS mutational gene profile of metastatic colorectal cancer patients in Jordan

BACKGROUND

A constitutively active RAS protein in the absence of stimulation of the epidermal growth factor receptor (EGFR) is the result of mutations in KRAS and NRAS genes. Mutations in the KRAS exon 2 and outside exon 2 have been found to predict the resistance to anti-EGFR monoclonal therapy. A substantial proportion of metastatic colorectal cancer cases (mCRC) exhibit RAS mutations outside KRAS exon 2, particularly in KRAS exon 3 and 4 and NRAS exons 2 and 3. No data about RAS mutations outside KRAS exon 2 are available for Jordanian patients with mCRC. We aim to study the molecular spectrum, frequency, and distribution pattern of KRAS and NRAS mutations in Jordanian patients with mCRC.

METHODS

A cohort of 190 Jordanian metastatic colorectal cancer patients were enrolled in the trial. We detected mutations in exon 2 of the KRAS and NRAS gene as well as mutations outside of exon 2 using the StripAssay technique. The KRAS StripAssay covered 29 mutations and 22 NRAS mutations.

RESULTS

Mutations were observed in 92 (48.42%) cases, and KRAS exon 2 mutations accounted for 76 cases (83.69%). KRAS G12D was the most common mutation, occurring in 18 cases, followed by KRAS G12A in 16 cases, and G12T in 13 cases. Mutations outside of KRAS exon 2 represented 16.3% of the mutated cases. Among those, 6 cases (6.48%) carried mutations in NRAS exon 2 and 3, and 10 cases (10.87%) in KRAS exon 3 and 4.

CONCLUSION

The frequency of NRAS and KRAS mutations outside of exon 2 appears to be higher in Jordanian patients in comparison with patients from western countries. KRAS mutations outside of exon 2 should be tested routinely to identify patients who should not be treated with anti-EGFR antibodies.

Contributing factors to iron deficiency anemia in women in Jordan: A single-center cross-sectional study

Objectives

This study aimed to understand the impact of iron deficiency anemia in female users of a hematology service in a developing country.

Design

Retrospective cross-sectional study of adult and adolescent women with iron deficiency anemia who presented to a hospital department of hematology.

Setting

A tertiary university hospital inpatient and outpatient hematology service.

Participants

All female patients who were ≥13 years of age with confirmed iron deficiency anemia and received hospital hematology services.

Results

A total of 208 patients were enrolled and analyzed in the registry. The mean age of the patients was 41.4 years (range, 14–82). A total of 195 patients had anemia that was moderate or severe according to the World Health Organization anemia classification with 13 patients having mild anemia. A total of 108 patients had comorbidities, which were primarily endocrine and cardiovascular. Iron deficiency anemia was associated with very heavy (n = 56, 30%) or heavy menses (n = 84, 45%) in 140 patients and was associated with poor (<200 g/week of red meat) (n = 101, 54%) or very poor (vegan, strict vegetarian) nutrition (n = 34, 18%) in 135 patients. A total of 101 patients had a previous pregnancy history with a mean of six previous pregnancies (range, 1–11 pregnancy episodes per patient). Blood film was performed on all patients; only four had a picture consistent with thalassemia minor.

Conclusion

Iron deficiency anemia is caused by multiple factors. Heavy menses and low consumption of red meat were found to be associated with the severity of anemia. Our findings may be useful for healthcare planners and policy makers in increasing efforts to reduce the prevalence and severity of iron deficiency anemia among women in Jordan.