Abstract P1-05-07: Detection of progression or regression of breast cancer by circulating tumor DNA (ctDNA)

Background: Circulating tumor DNA (ctDNA) are short DNA sequences shed by tumor cells into the systemic circulation. Studies have shown potential utility of the test to predict relapse or recurrence following treatment in solid tumors, but sensitivity and specificity have varied widely, ranging from 19-100% and 80-100% respectively, in breast cancer specifically. Moreover, literature describing the utility of monitoring dynamic changes in ctDNA trends is limited. We aim to evaluate the correlation between ctDNA test, both single test as well as dynamic trends in value over time, with imaging findings.

Methods: We retrospectively analyzed the medical records of all adult patients diagnosed with breast cancer who underwent ctDNA testing at the hematology-oncology clinic at William Beaumont - Royal Oak and Troy Hospitals, Michigan, from August 2017 to June 2022. Patients who had ctDNA testing done but did not have imaging to correlate it with were excluded from the study. We calculated the sensitivity and specificity of a single positive ctDNA test to detect disease progression or residual disease on imaging. In patients with multiple ctDNA tests, we calculated the sensitivity and specificity of dynamic trends in ctDNA values to detect progression, regression, or absence of disease on imaging. Moreover, we calculated the lead time for positive ctDNA results to detect disease progression compared to imaging.

Results: Nineteen patients were included in the study, with 34 total ctDNA test results, each utilized as a separate data point to compare with corresponding imaging findings (Table 1). Ten out of the 19 patients had multiple(>=2) ctDNA test results reported, with a total of 15 pairs of ctDNA values and each pair was analyzed separately as up trending (N=7), down trending (N=4), or persistent negative (N=4) to compare with a corresponding pair of imaging findings (Table 2). The median age at diagnosis was 55 years, and 94.7% were female. At diagnosis, majority of patients (68.4%) had either stage III or IV disease. Our primary endpoint, the correlation of single positive ctDNA result with imaging showing either progression or residual disease, showed a sensitivity and specificity of 100% and 93.3%, respectively. Secondarily, serial ctDNA trend analysis in ten patients revealed both sensitivity and specificity of 100% for up-trending ctDNA values to detect progression, down-trending to detect regression, and persistent negative results to detect absence of disease on imaging, respectively. The positive ctDNA results detected disease progression with a median lead time of 44.5 days compared to imaging.

Conclusion: Given the high sensitivity and specificity to detect disease progression and regression in breast cancer patients by single ctDNA results and dynamic ctDNA trends in our study, we conclude that this may be a valid way to reliably monitor for changes in disease status before they become evident in imaging studies. Further clinical studies are required to prove the utility of ctDNA to detect changes in disease status and to guide therapeutic interventions in breast cancer.

Table 1. Correlation of single ctDNA result with imaging findings.

Table 2. Correlation of dynamic trends in ctDNA values with imaging findings.

Citation Format: Ujjwal Karki, Bipin Ghimire, Emma Herrman, Siddhartha Yadav, Mohammad Muhsin Chisti. Detection of progression or regression of breast cancer by circulating tumor DNA (ctDNA) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P1-05-07.

Development of Merkel Cell Carcinoma in a Patient Receiving Rituximab

Merkel cell carcinoma (MCC) is a rare, rapidly growing, and aggressive dermatological neoplasm. It is commonly reported in Caucasian ethnicities, and almost 50% of the patients have a concomitant malignancy and are on immunosuppressive chemotherapy. Here, we present a 79-year-old woman with a history of relapsed Stage II, grade III follicular lymphoma, receiving maintenance rituximab infusions. She presented with a raised erythematous papule on her left cheek. An excisional biopsy of the lesion confirmed a diagnosis of Merkel cell carcinoma. After which, she underwent a wider excision with 1-2 cm margins. PET scan did not reveal any FDG-avid uptake lesions that would be concerning for metastatic disease. However, she underwent a sentinel lymph node biopsy which was also negative. Thus, the diagnosis was finalized as Stage I (T1 N0 M0) MCC. There are only two reported cases in literature about the significant progression of Merkel cell carcinoma in patients who coincidentally were receiving rituximab as a part of treatment for another disease. This raises questions for future investigation and research on whether there is a direct association between rituximab use specifically and the rapid growth of MCC.

Use of circulating tumour DNA in nasopharyngeal carcinoma to detect minimal residual disease

Circulating tumour DNA (ctDNA) is defined as short DNA sequences shed by tumour cells into the systemic circulation. A promising use of ctDNA includes the detection of minimal residual disease (MRD) and is currently being studied in multiple types of solid tumours. Literature for the use of individualised ctDNA in nasopharyngeal carcinoma (NPC) is not available, although circulating Epstein-Barr virus DNA level is validated as a prognostic factor. We present a man in his 40s diagnosed with stage IV NPC who was started on chemotherapy with cis-platinum and gemcitabine. Serial monitoring of ctDNA completed to aid in detecting MRD after treatment demonstrated initial up-trending values correlating with subsequent imaging findings showing progression. Reinitiation of a different chemotherapy regimen significantly improved the ctDNA level, with corresponding imaging exhibiting a similar response. This case provides insight into the potential use of ctDNA in NPC and the benefit of serial ctDNA monitoring during treatment.

Thrombotic thrombocytopenic purpura following administration of the Moderna booster vaccine

Thrombotic thrombocytopenic purpura (TTP) is a type of thrombotic microangiopathy that is characterized by microangiopathic haemolytic anaemia, consumption thrombocytopenia and organ injury. It is caused by a severe deficiency of ADAMTS13, which can be either congenital or acquired. There is a plethora of things that can cause the acquired form, including medications and infections. Vaccines have also been shown to cause TTP. In the midst of the COVID-19 pandemic, with multiple new vaccines being developed and distributed to the masses, the medical community needs to be aware of adverse events associated with these new vaccines. We present a case of TTP following administration of the Moderna booster vaccine.

A Systematic Comparison of Overall Survival Between Men and Women With Triple Negative Breast Cancer

INTRODUCTION

Triple-negative breast cancer (TNBC) in men is very rare. The clinical characteristics, prognostic factors, and overall survival of men with TNBC have not been characterized.

METHODS

The study population consisted of men and women with a diagnosis of stage I-III TNBC between 2010 and 2016 in the National Cancer Database. Baseline demographic and tumor characteristics between men and women were compared using Pearson's Chi-Square test for categorical variables and Mann-Whitney U test for continuous variables. Kaplan-Meier and multivariate Cox proportional hazards regression model was used to compare survival and identify prognostic factors.

RESULTS

A total of 311 men and 95,406 women with TNBC were included in the final analysis. The 3-year and 5-year overall survival was 74.8% and 68.8% in men, while it was 83.2% and 74.8% in women, respectively. In multivariate analysis, men were found to have a significantly worse overall survival compared to women (HR, 1.49, 95% CI, 1.19-1.86, P= .01). Older age at diagnosis, higher TNM stage, undergoing mastectomy and not undergoing chemotherapy or radiation were identified as independent negative prognostic factors in men with TNBC.

CONCLUSION

In one of the largest studies of men with TNBC, men were noted to have a poorer overall survival compared to women, despite adjusting for usual prognostic factors. Further research into differences in tumor biology, treatment patterns and compliance with therapy between men and women are needed to understand the underlying etiologies for the survival difference in TNBC.

Adult Xp11.2 translocation renal cell carcinoma managed effectively with pazopanib

Xp11.2 translocation renal cell carcinoma (TRCC) is a rare and aggressive variant of renal cell carcinoma (RCC) when presenting in adults. We report a case of a man in his early 40s who was diagnosed with stage III Xp11.2 TRCC and underwent radical nephrectomy. Seven months following the surgery, an adrenal nodule and bilateral pulmonary nodules were discovered. He underwent cryoablation of the adrenal nodule and systemic treatment with daily pazopanib. He displayed stable disease for approximately 6 years. Following this period, multiple hospitalisations interrupted daily pazopanib therapy resulting in progression of disease. His regimen was then changed to ipilimumab and nivolumab, followed by current daily therapy with axitinib. The patient now shows stable disease in his 10th year after diagnosis. This case study demonstrates the efficacy of pazopanib for metastatic Xp11.2 TRCC and warrants further investigation to supplement the guidelines regarding the use of targeted therapy for TRCC.

MDS with 5q deletion and rare cKIT positive mastocytosis: a diagnostic and therapeutic challenge

A patient with a diagnosis of myelodysplastic syndrome (MDS) with isolated 5q deletion underwent repeat bone marrow biopsy to assess haematological response after 6 months of initial lenalidomide therapy. Subsequent bone marrow biopsies revealed persistent MDS with del(5q) in addition to a small atypical mast cell population with >25% of mast cells with spindle-shaped morphology and immunohistochemistry characteristics consistent with mastocytosis. Molecular testing on the bone marrow was positive for cKIT D816V and the patient was diagnosed with systemic mastocytosis (SM) with an associated haematological neoplasm. MDS with SM is well known to be associated; however, to the best of our knowledge, only one prior case report identifies MDS with del(5q) and associated cKIT D816V positive mastocytosis. While the exact clonal origin of both chromosomal aberrations is unclear, this case illustrates the therapeutic efficacy of lenalidomide in a patient with MDS with del(5q) and rarely associated cKIT positive SM.

Rare case of catastrophic antiphospholipid syndrome with spontaneous intracranial haemorrhage

Catastrophic antiphospholipid syndrome (CAPS) is a rare but severe form of antiphospholipid syndrome (APS). The syndrome manifests itself as a rapidly progressive multiorgan failure that is believed to be caused by widespread micro-thrombosis. Seldom does bleeding comanifest with thrombosis. We present a patient with APS who presented with nausea, vomiting and fatigue, and rapidly progressed into multiorgan failure before being diagnosed with CAPS. The clinical course was complicated by an atraumatic intracranial haemorrhage which demanded discontinuation of anticoagulation. The patient was treated with high dose steroid, intravenous immunoglobulin, followed by weekly rituximab infusion. Although the trigger for CAPS was not obvious during her hospital stay, she was diagnosed with acute cytomegalovirus (CMV) infection soon after discharge. In this case report, we explore the differential diagnoses of CAPS, investigate the possibility of CMV infection as a potential trigger, present the therapeutic challenges of anticoagulation and discuss the emerging use of rituximab.

Chronic Myeloid Leukemia with b3a3 (e14a3) Fusion: A Rare BCR/ABL Rearrangement Presenting with Thrombocytosis - Does MTHFR Polymorphism Matter

Fusion of b2a2 is the most common BCR/ABL rearrangement in CML; however, absent a2 exons are very rare. We describe a case with Philadelphia-positive chronic myeloid leukemia (CML) with a very rare b3a3 (e14a3) BCR/ABL junction. To our knowledge, only 15 such cases of CML have previously been reported. These uncommon transcripts may be under-reported, since RT-PCR-based assays may fail to detect these fusions due to the location of the primers and probes used. We are reporting this case for the first time which presented with MTHFR mutation and significant thrombocytosis. There is very limited information on how this genotype expresses and responds to treatment, especially to tyrosine kinase inhibitors, as compared to classic CML. Also, the relationship between MTHFR mutation and CML is not clear, although studies have been done.

Idiopathic Thrombocytopenia Purpura Masking Hodgkin Disease: A Paraneoplastic Syndrome or Simply a Mere Association?

We report a 74-year-old female who presented to the emergency department complaining of bruising and stroke-like symptoms. She underwent a negative stroke work-up but was found to have profoundly low platelets and splenomegaly on examination. An abdominal CT scan was ordered, showing pelvic lymphadenopathy. Lymphoma was suspected. However, subsequent bone marrow and lymph node biopsies showed no evidence of this. She was treated for immune thrombocytopenia purpura (ITP) to no avail while a lymphoma work-up continued. Months later, a third and final lymph node biopsy yielded evidence of Hodgkin disease (HD) and she began treatment shortly thereafter. She is currently undergoing standard treatment for this malignancy and her platelet counts have normalized. The case not only outlines the importance of the physician's gestalt in arriving at the proper diagnosis, but it also posits the thought that perhaps ITP should be considered a paraneoplastic syndrome of HD.

Trastuzumab (T) detection in serum using signal amplification strategy for non-faradaic impedimetric sensing quartz crystal microbalance (QCM) based on peptide piezo-immunosensors and its role in breast cancer treatment

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Background: Her2Neu (H) antigen, expressed on 20% of Breast cancers, is an established target for antibody therapy with T. Immunohistochemistry is still the most widely used technique to detect h level which is time consuming and does not reveal any details of interaction between the molecules. We have developed a new innovative biosensor based novel technique to study real time interaction of h antigens with T using QCM Piezo-immunosensor. This quantitative label free peptide based assay can be used to characterize cell surface antigen, to study antigen- antibody interactions and obtain understanding of mechanisms of resistance. Methods: A label free and reagent free peptide mimotope capacitive biosensor is developed for T quantification based on non-Faradaic readout. The low sensitivity issue of capacitive biosensor was overcome with two innovations: peptide mimotope mixed SAM biointerface and dilution of the testing buffer. Signal amplification was achieved through dilution of the PBS buffer to tune Cdl to dominate the overall capacitance change upon target binding. After 1000 times dilution, limit of detection is lowered 500 times (0.22 µg/mL) and the sensitivity increased 20 times (0.04192 (µg/mL)-1). Results: Binding was very specific. Signal amplification strategy is practical. Further applied to planar electrode for optimizing sensing, response time in less than 1 minute. Conclusions: This is the first report of T detection using electrochemical method based on non-Faradaic impedance. h antigen density and interactions of antigens will help physicians to determine the clinical efficacy and resistance mechanisms to targeted antibodies like T and ado-Trastuzumab.For the first time, we have established a low cost, highly sensitive, fast, synthetic, QCM assay which could be used as a basis for developing a new generation of affinity-based Immunosensor assays. This real time capability and its simplicity of operation are highly suitable for multipurpose studies on living cells including cell immobilization, cytotoxicity of drugs, and the cell action mechanisms

General Signal Amplification Strategy for Nonfaradic Impedimetric Sensing: Trastuzumab Detection Employing a Peptide Immunosensor

A label-free and reagent-free peptide mimotope capacitive biosensor has been developed for cancer drug (trastuzumab) quantification based on nonfaradic readout. The low sensitivity issue of capacitive biosensors was overcome with two innovations: peptide mimotope mixed self-assembled monolayer (SAM) biointerface and dilution of the analysis buffer. Signal amplification was achieved through dilution of phosphate-buffered saline (PBS) to tune C_dl to dominate the overall capacitance change upon target binding, which contribution is often negligible without dilution. After 1000× dilution, the limit of detection was lowered 500-fold (0.22 μg/mL) and the sensitivity was increased 20-fold [0.04192 (μg/mL)^-1] in comparison with undiluted PBS. The proposed signal amplification strategy is more straightforward and practical compared to biorecognition element engineering and other strategies. The proposed method was further applied to planar electrodes for optimizing sensing response time to less than 1 min.

A Rare Case of Metastasis of Small Cell Carcinoma of Cervix to Breast

Extrapulmonary small cell carcinomas (SCCs) are rare and often have an aggressive natural course. A 42-year-old female presented to the hospital with vaginal bleeding and lower abdominal pain. She was eventually diagnosed with SCC of cervix by biopsy. She was treated with chemoradiation. However, on follow-up positron emission tomography (PET) scan, fluorodeoxyglucose (FDG) uptake was noted in bilateral breasts. Biopsy of these lesions was consistent with metastatic SCC. Breast is a very unusual site for metastasis of cervical SCC and only four cases have been reported in the medical literature to date. Our case highlights the importance of considering metastatic disease when evaluating breast mass in patients with history of SCC of cervix.

Dasatinib-induced haemorrhagic colitis in chronic myeloid leukaemia (CML) in blast crisis

We report a rare case of haemorrhagic colitis attributed to dasatinib therapy in a 47-year-old African-American woman who was diagnosed with extramedullary T-lymphoblastic transformation of chronic myeloid leukaemia. The patient received intensive chemotherapy and dasatinib 100 mg/day. After achieving complete cytogenetic and major molecular response after 9 months of therapy, she developed bloody diarrhoea and pancytopenia. Colonoscopy showed inflammation of the descending colon and histopathology revealed patchy increase in intraepithelial lymphocytes. Dasatinib was stopped with prompt resolution of diarrhoea. The current literature suggests that there is an association in a subset of patients on dasatinib between clonal T-cell lymphocytosis in the peripheral blood and developing colitis and pleural effusions. These patients had a good response to dasatinib as did our patient. Our patient illustrates a unique disease presentation along with a rare drug adverse event.

Aggressive plasmablastic multiple myeloma in a 42-year-old: is inflammatory bowel disease or infliximab treatment to be blamed?

A man in his early 40s with a history of ulcerative colitis, treated with infliximab, was diagnosed with plasmablastic multiple myeloma. He was treated with chemotherapy and stem cell transplant but developed recurrence and ultimately died from metastatic disease. Could inflammatory bowel disease or infliximab therapy have any role in development of myeloma in this young patient? The role of inflammatory bowel disease and infliximab therapy in the development of multiple myeloma is controversial but interesting and worth considering.

Peripheral T-cell lymphoma in a patient with Crohn's disease

A 46-year-old man with a long-standing history of Crohn's disease who was treated with multiple therapies over a period of 9 years presented with oral lesions which on biopsy demonstrated peripheral T-cell lymphoma. Initially, the development of T-cell lymphoma was presumed to be secondary to prolonged immunosuppression but it did not respond to withholding immunosuppressive therapy. On treatment with CHOP (cyclophosphamide, hydroxydaunorubicin, oncovin and prednisone) chemotherapy, complete remission was achieved. Although development of malignancies in the immune-suppressed patient with Crohn's disease has been previously described but we present a rare case of T-cell lymphoma in a similar patient, which has not been reported before.

Unique genetic characteristics of BRCA mutation carriers in a cohort of Arab American women

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Background: Worldwide ethnic variations in the distribution of BRCA1 and BRCA2 mutations of breast cancer patients have been recently recognized. This has led to investigations of the epidemiology, genetics and clinical characteristics of BRCA positive individuals within specific populations. This study aims to describe the findings of BRCA genetic testing in a cohort of Arab American women. Methods: A total of 73 women of Arab ancestry were evaluated in the Beaumont Cancer Genetics Program from Jan 2008 to Jan 2013. Criteria for genetic testing included a personal or family history suggestive of Hereditary Breast and Ovarian Cancer Syndrome (HBOC). Patients underwent comprehensive genetic counseling, followed by full sequence analysis for germline mutations in BRCA1 and BRCA2. Results: 63 women of Arab ancestry underwent genetic testing for BRCA1 and BRCA2. 13 (21%) patients were found to be mutation carriers, of whom 10 (16%) of the 63 had deleterious mutations (7 in BRCA2, and 3 in BRCA1), and 3 (5%) had variants of undetermined significance (VUS) in BRCA2. Of the 10 patients with deleterious mutations, 4 (40%) unrelated individuals had the same mutation, 5804del4, in exon 11 of BRCA2. The remaining patients had deleterious mutations in exon 2, exon 20, and exon 13 of BRCA2; one patient had a BRCA1 and BRCA2 mutation (exon 18). 7 of 10 patients with deleterious mutations had a cancer diagnosis, of which 5 had breast cancer, 1 had ovarian cancer, 1 had pancreatic cancer, and 3 were unaffected. Conclusions: This study demonstrates that BRCA mutations (predominantly in BRCA2) were seen in a significant proportion of Arab American women undergoing genetic testing for HBOC. A mutation in BRCA2, 5804del4, was seen in nearly half (4/10) of the carriers of deleterious mutations. This mutation, in exon 11, has not previously been associated with Arab ethnicity and may represent a founder mutation. Knowledge of the genetic spectrum, frequency, and clinical characteristics of BRCA mutation carriers will lead to greater understanding of hereditary cancer in Arab American women.

Detection of trastuzumab (T) level in human serum using quartz crystal microbalance (QCM) piezo-immunosensors by immobilization of a HER2 mimotope-derived synthetic peptide and its potential application in breast cancer

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Background: Varied clinico-pathological response to monoclonal antibodies like T has been reported either due to presence of antibodies, rapid clearance or low density of target receptor/antigens. This demands need for an assay to monitor serum T therapeutic levels to ensure appropriate dosage. Enzyme-linked immunosorbent assay (ELISA) is still the most widely used technique to detect T level in human serum which is expensive and time consuming. For the first time, we established a platform to detect T level by using a small (<2.2 kDa), inexpensive, highly stable HER2 mimotope-derived synthetic peptide immobilized on the surface of a gold quartz electrode. Methods: HER2 mimotope was used as a substitute for the HER2 receptor protein in QCM assays to detect T level. The validation samples were prepared from the standard T solution in 10% human serum at three concentrations (10, 20 and 40 ug/ml). The changes in frequencies (ΔF) of sera from 3 female patients , 61, 32 and 44 years old , with ER/PR positive, HER2/neu positive metastatic breast cancer were obtained by calculating the differences between frequency shifts in pre and post T infusion.T level was calculated by equation, (ΔF +1.0022) ÷ 0.9997 μg / ml. Results: We showed that assay sensitivity was dependent upon the amino acids used to tether and link the peptide to the sensor surface and the buffers used. QCM assay was capable of detecting T serum level as low as 0.038 nM (linear operating range of 0.038–0.859 nM). T levels of 3 patients were 43.34, 121.96 and 193.18 μg /ml corresponding to pre and post infusion ΔF of 3.33, 11.19 and 18.31 respectively. The time frame of assay was 20-30 minutes. These results were in concordance with previously published results using ELISA. Conclusions: For the first time, we have established a low cost, highly sensitive, fast, synthetic peptide based QCM assay which could be used as a basis for developing a new generation of affinity-based Immunosensor assays to monitor serum levels of T and other monoclonal antibodies, helping physicians to determine the clinical efficacy of these drugs and ensuring appropriate dosages.

How we treat tumor lysis syndrome

Tumor lysis syndrome (TLS) is an oncology emergency that occurs as a result of rapid tumor cell breakdown and the consequent release of massive amounts of intracellular contents, including potassium, phosphate, and uric acid, into the systemic circulation. These metabolic disturbances lead to life-threatening conditions and may cause sudden death if not treated. TLS commonly occurs following initiation of cytotoxic treatment in patients with high-grade lymphomas or acute lymphoblastic leukemia. Spontaneous cases involving both solid and hematologic tumors have also been reported. Rarely, TLS occurs following treatment with irradiation, corticosteroids, hormonal therapy, or biologic therapy. It is necessary to identify patients at risk for TLS early in order to initiate preventive measures. In the event that preventive measures fail, the clinical parameters and signs of TLS must be understood and recognized so that treatment can begin as soon as possible, as this condition is a significant cause of morbidity and mortality.