Understanding the Biology and Treatment Options for Breast Cancer

by Anthony M Magliocco MD

Breast cancer is a common disease with up to 1 in 8 women receiving this diagnosis in her lifetime. It is more common in older women but it certainly can strike the young and even can occur in men at about 1/100 the rate seen in women.

We have learned a lot about the biology of breast cancer over the years and the condition is becoming easier to detect at an earlier stage and fortunately more effective therapies are now being developed.

We now know that breast cancer is complex and has multiple molecular and biological subtypes. The main types are called Luminal A, Luminal B, HER2 positive, and Triple Negative.

Luminal Cancers – Endocrine responsive tumors

The Luminal types of breast cancer are defined by expressing estrogen receptor. They tend to have better differentiation and generally a more indolent course. The standard treatment is surgery, potentially radiation, and endocrine treatment (an anti estrogen agent) for 5 to 10 years. If the tumor appears more aggressive- ie involves lymph nodes, or has higher grade, chemotherapy may be added to the treatment in an adjuvant way. One of the problems with luminal type breast cancer is it can recur many years after the original cancer has been treated. Its thought the cancer cells can spread and remain dormant in distant organs or bone for many years with some mysterious events causing them to become reactivated.

 

The HER2 positive breast cancers

A subset of breast cancers, about 15% seem driven by the oncogene ERBB2 (which produces the protein HER2).  For some reason this gene can become “amplified” – ie many copies are made in a single cell leading to vast over production of the HER2 protein. This over production seems to drive the cancer cell to proliferate and metastasize.

Fortunately, therapies have been designed for HER2 cancer, these include Trastuzumab and Pertuzumab – antibodies that react and block the function of the HER2 gene. These treatments appear to be able to halt the grow of the cancer and prevent metastases from occurring.

The Triple Negative Breast Cancers (TNBC)

The third main type of breast cancer are the Triple Negative Cancers or TNBC. This group is actually a mixed group of tumors defined by lack of expression of estrogen receptor or HER2.  They frequently occur in younger women, they may be familial, are over represented in African American women and often progress more quickly. Some of them seem to have a high immune infiltrate, some carry the BRCA gene mutation, and some show strange growth characteristics such as bone formation or “metaplasia”.

 

 

The problem with TNBC is they are a generally a diagnosis by exclusion. However there are certain tests a pathologist can order to help prove that a cancer is TNBC such as Nestin.

Because the TNBC is diagnosed by exclusion there is a significant possibility of error. For example some tumors are heterogenous, and only a small portion might be sampled. If the portion is ER negative or HER2 negative the tumor might be erroneously classified as TNBC.

In other cases, TNBC cancers with very low false expression of HER2 or ER may end up being misclassified as HER2 positive or ER positive which could lead to erroneous use of potentially toxic and ineffective anti -HER2 therapy

Use of Second opinion Expert Review Pathology 

A second opinion pathology review by an expert pathologist can help a patient and her oncology be confident that a tumor is indeed a TNBC. The pathologist may order a repeat immunohistochemical stain on additional case material which frequently changes a diagnosis of TNBC to ER positive or HER2 positive. Occasionally a ER positive or HER2 positive will be reclassified as TNBC also.

TNBC is a unique form of breast cancer with subtypes. further classification of TNBC into tumors with BRCA mutation will help with selection of Parp inhibitor or chemotherapy with carboplatinum.

Further, some TNBC tumors have been shown to be sensitive to immunotherapy.

Some TNBC also seem to express androgen receptor, which could be a therapeutic target.

 

Use of Liquid Biopsy

In some patients a liquid biopsy could also be helpful. If a patient has metastatic disease the cancer cells can be isolated and analyzed from a blood sample.  ER and HER2 status can be measured in these circulating tumor cells. In addition fragments of DNA from disintegrating cancer cells can also be measured and classified providing further evidence as to the amount of cancer and whether the cancer is changing or responding to therapy.

Of interest, it seems that breast cancers may undergo biomarker change as they progress or metastasize. for example an ER positive tumor might change and become ER negative or switch to HER2 overexpression.

Patients should seek second opinion pathology review if they have concern regarding the accuracy of their diagnosis or want to ensure that all treatment opportunities are properly considered.

 

 

As treatment options continue to expand, and testing methods improve, it is important that patients with breast cancer have access to the highest quality pathology services and they should also not hesitate to seek second opinion if there is concern regarding the accuracy of diagnosis.

Morsani Molecular Lab at Moffitt Cancer Center is Central to its Personalized Oncology Mission

By Anthony M Magliocco MD

Moffitt Cancer Center, the largest and only NCI designated comprehensive cancer center in Florida and one of the largest in the country has been rapidly expanding its capabilities in molecular diagnostics with a clear focus on supporting its burgeoning personalized oncology programs which are led by internationally recognized expert Dr Howard McLeod.

It became clear several years ago that a huge revolution was coming in the area of personalized oncology and cancer treatments. That revolution is now here.

Explosive advances and numerous FDA approvals for new targeted therapies have emerged for treating and controlling once universal killers such as metastatic melanoma and advanced lung cancer.

These targeted therapy medicines, include vemurafenib targeting mutant BRAF, Erlotinib for EGFR mutant lung cancer, and crizontinib targeting ALK translocations. Further truly dramatic results have been seen with immunotherapy treatments such as the anti PDL-1 immune checkpoint inhibitor pembrolizumab for treatment of a variety of advanced cancers that over express the protein PDL-1 or carry MSI. More recently approvals of NTRK inibitors Larotrectinib and the PARP inhibitor Olaparib for BRCA mutant cancer have further increased demand for specialized testing as both of these treatments have companion diagnostic requirements

 

Immune cells (red and blue) surround a invasive cancer cells (green)

The approval of many new targeted treatments requiring companion biomarker evaluation is providing impetus to develop more advanced diagnostic technology including new cellular imaging methods

These rapid advances in treatment options hinge on the availability of routine, high quality, clinical grade, molecular analysis and diagnosis to properly identify patients who will be most likely to benefit from these costly and frequently toxic treatments.

The Morsani Molecular Laboratories were created to facilitate the rapid development and implementation of new molecular diagnostic assays into the routine CLIA laboratory at Moffitt

Moffitt leadership and its generous philanthropic doners and foundation laid the important cornerstone of the Moffitt Morsani Molecular Laboratories. Under the direction of Dr Magliocco, the laboratories had a singular mission to rapidly develop and deploy the advanced clinical grade diagnostic services necessary to support Moffitts rapidly maturing personalized medicine program.

The Laboratories were initially opened in 2012 and were first equipped with Mass array instruments and conventional Sanger sequencing, pyrosequencing and routine PCR ability. The decision was made to recruit PhD scientists who would help develop the new assays to a CLIA standard and then launch them into a “routine” production laboratory.

The demand from the Moffitt clincal services was high, especially from thoracic oncology, a ground breaking team offering a multitude of clinical trail options for Moffitt patients. This demand required that the assays be CLIA grade, complex and delivered in a rapid way.

This was very challenging. Launching a highly multiplex assay into a CLIA lab is not a trivial matter. The assay must be calibrated to show sensitivity, specificity, analytical performance, range, precision, accuracy and many other technical components. Further, any new assay must also be put through its paces to show its robustness and reproducibility when handled by different scientists and technologists.

Launching new assays into CLIA labs is not trivial and requires extensive expertise and investments

We initially chose to launch the LungCarta (TM) Mass Array Panel from Sequenom. This was very challenging to validate as it contained individual assays run in multiplex to assay over 213 distinct mutations. as these were separate mutations and assays, the decision was made to only validate the most clinically important ones, namely BRAF V600E, KRAS, EGFR, and PIK3CA. The next issue was obtaining appropriate clinical reference materials to validate these assays. Fortunately with Moffitt’s very high clinical volume, previous experience with single-plex testing, and availability of Total Cancer Care Protocol tumor bank which houses data and specimens from over 400,000 patients it was possible to obtain the necessary control and case materials to validate and launch the assays into clinical service.

The development of a CLIA assay requires access to appropriately characterized reference materials to enable clinical validation of the process and assay results.

Although the complete 213 mutation panel was run, only the CLIA validated assay results were reported to the treating physician. The remaining results were ported into Moffitt’s data warehouse for storage and use in properly approved research studies. Following the launch of the LungCarta assay, the Morsani Molecular laboratory also launched assays for melanoma, and a specially constructed Glioma panel assay.

 

In 2014, clinical demands for even more complex sequencing arose for proper management of Myelodysplastic Syndrome (MDS) mounted. The hematology team needed access to over 30 genes and potentially thousands of mutations. It was time for the big guns, time for next generation sequencing. At the same time Moffitt molecular pathologists also saw increasing needs for more complex sequencing for solid tumors as well. After careful discussions and further evaluations it was decided to begin next generation sequencing. Following some debate, the consensus was to start with Illumina, given their long history in next gen sequencing and also the experience with the technology in Moffitt’s core genetic research laboratory. It was decided to develop an off the shelf 26 gene panel TST26 that covered most of the key mutations in lung cancer and in melanoma. In addition Moffitt CLIA scientists, molecular pathologists, and clinicians worked with Illumina to design a 32 gene myeloid NGS panel.

Bringing on NGS brought new challenges of a complex wet lab and also a very complex bioinformatics dry lab. At Moffitt we worked with PierianDx who helped design bioinformatics pipelines and an efficient validation program for both the wet and dry lab as well as an information system – a genome workbench- which allows molecular pathologists to rapidly review cases and access a knowledge database to enable rapid sign out. We also required access to numerous control samples to validate the assays. Again these came from Moffitts vast biospecimen resources and also Horizon Discovery, a company specializing the the provision of reference materials for clinical validations. To date Moffitt has run over 10,000 NGS assays.

By 2017, clinical demands continued to mount for even more complex testing. There were new drugs approved that needed to evaluate fusions, “exon skipping” mutations, and even MSI and tumor mutational burden. With these demands, we turned to illuminas TST170 assay, a new type of sequencing assay that had both DNA and RNA. In addition the assay was designed with “actionable targets” in mind. Meaning, that targeted agents in clinical trials were scrutinized to determine the collection of genes and mutations that would likely be most informative for treatment selection in solid tumor oncology. This approach makes the assay very useful and practical for deployment in a busy cancer center where multiple trials are underway and complex patients with unusual cancers are presenting. Moffitts Morsani molecular team worked hard and spent several months validating the assay to bring it to acceptable CLIA standard finally launching it as “Moffitt STAR” an assay to screen for actionable mutations.

Since its launch, demand has been exceptionally high with hundreds of physician orders in the first week alone.

 

Moffitt laboratories continue to work closely with the worlds leading oncologists and pharma and technology companies to ensure that Moffitt Patients always have access to the latest diagnostic tools to enable them access to the most current treatment options.

That is what makes Moffitt an exceptional hospital for cancer patients seeking innovative treatments and explains why Moffitt has some of the best cancer outcome response rates in the country.

 

New Window into Brain Metastasis Using Modified CTC and cfDNA Technologies

Anthony M Magliocco MD

Many cancers metastasize to the central nervous system including the brain and its coverings, the leptomeninges. These cancers are difficult to treat and monitor. The so called “liquid biopsy” is making excellent progress in monitoring disease progression and response using blood samples in patients with disseminated solid tumors. In this technique, either circulating tumor cells (CTCs), or cell free DNA (cfDNA) can be harvested and captured for analysis.

These new “real time” monitoring methods create a new opportunity to monitor cancer progression and evolution while patients are actually under therapy- for example are the number of circulating tumor cells increasing, or is their phenotype evolving into something different.

For example, metastatic breast cancer cells may change their receptor status to go from estrogen receptor positive to negative, or they may acquire a new targetable change, for example acquiring HER2 over expression.

Images of circulating tumor cells captured in the Cell Search System

Intact tumor cells might also allow for examination of activation of signalling cascades and perhaps a pharmacodynamic read out.  One of the challenges of CTCs is their extreme fragility- with current method they generally need to be captured and examined within 48-72 hours. These cells also tend to be exquisitely rare, especially in early stage disease raising questions as to how representative they may be of the systemic disease.

 

Cell Free DNA cfDNA

A complementary assay method,  the measurement of cell free DNA (or cfDNA), provides a new application for monitoring cfDNA in patients. It has found widespread use monitoring lung cancer patients for the development of tyrosine kinase resistance while under therapy.  A common mechanism of resistance is the the switch or evolution to EGFR T790M mutation that portends the looming end of response to first generation TKI drugs and an opportunity to intervene with a switch to the 3rd generation Osimertinib therapy.

Liquid Biopsy is a powerful method to enable real time monitoring of solid tumor evolution and response to therapy using a blood sample to cature CTCs and cfDNA. Unfortunately, this does not typically work for CNS tumors due to the blood brain barrier

Unfortunately tumors occurring or metastasizing to the CNS are not easily followed by blood tests due to the presence of the blood brain barrier. However, these tumors are in contact with the cerebrospinal fluid, a specialized liquid that circulates around the brain cushioning it.

This fluid can be extracted in small amounts for analysis using a spinal tap, or in some cases of patients with malignancy an in-dwelling catheter is placed to enable CSF to be drained off to reduce the central nervous system pressure. This CSF fluid is traditionally sent to pathology for cytopathology analysis. Unfortunately standardized cytopathology methods do not lend themselves to evaluation of rare cells and molecular events in CSF.

 

Because CSF is very similar to blood, we reasoned that liquid biopsy methods used for blood samples might be potentially adapted for use on CSF samples. Recently, the Moffitt teams of the Neuro Oncology group, led by Dr Peter Forsyth and the Morsani Molecular Laboratory teamed up to attempt to modify the liquid biopsy procedures currently used for blood to adapt for CSF.

The current CTC platform in use at the Morsani Molecular Laboratory at Moffitt is the CellSearch system which is designed for magnetic capture of EPCAM expressing carcinoma cells in blood followed by evaluation of keratin expression in an automated scanning step with exclusion of non- specific cells using stains for nuclei and lymphocytes.

The adaptation of this system for analysis of melanoma in CSF was not trivial, as the volume of CSF is significantly less requiring adjustments on the liquid handling approaches. Further, the Neuroncology team was particularly interested in metastatic and primary melanomas of the central nervous system. This required changing capture antibodies to CD146 which targets melanoma and visualization with MelPE.

The Moffitt Morsani Molecular Laboratory has Developed New Methods to Monitor Melanoma in the CSF using both CTCs and cfDNA approaches

We also determined that DNA could be extracted and sequenced from CSF using both the NGS sequencing methods and MassArray systems. Further, we determined that melanoma cells captured from CSF can be grown ex-vivo and cultured for further analysis.

These advances create new opportunities to apply advances from personalized oncology to patients with metastatic melanoma in the CSF and central nervous system enabling potential real time adaptation of treatment strategies based on directly monitoring tumor molecular responsiveness to therapy in real time \\.

REFERENCES

Fedorenko IV, Evernden B, Kenchappa RS, et al. A rare case of leptomeningeal carcinomatosis in a patient with uveal melanoma: case report and review of literature. Melanoma research. 2016;26(5):481-486. doi:10.1097/CMR.0000000000000274.

Neuro-Oncology, Volume 19, Issue suppl_6, 6 November 2017, Pages vi46,https://doi.org/10.1093/neuonc/nox168.183 Published: 06 November 2017

 

FDA approves osimertinib for first line use in lung cancer with EGFR mutation

By Anthony Magliocco MD

TAGRISSO delivered unprecedented median progression-free survival of 18.9 months versus 10.2 months for EGFR-TKIs (erlotinib or gefitinib) in 1st-line EGFRm NSCLC

 

the US Food and Drug Administration (FDA) has approved TAGRISSO® (osimertinib) for the 1st-line treatment of patients with metastatic non-small cell lung cancer (NSCLC) whose tumors have epidermal growth factor receptor (EGFR) mutations (exon 19 deletions or exon 21 L858R mutations), as detected by an FDA-approved test. The approval is based on results from the Phase III FLAURA trial, which were presented at the European Society of Medical Oncology 2017 Congress and published in the New England Journal of Medicine.

 

The results of the phase III FLAURA trial were impressive with dramatic improvements to progression free survival.

The FLAURA trial compared TAGRISSO to current 1st-line EGFR tyrosine kinase inhibitors (TKIs), erlotinib or gefitinib, in previously untreated patients with locally advanced or metastatic EGFR-mutated (EGFRm) NSCLC. TAGRISSO met the primary endpoint of progression-free survival. PFS results with TAGRISSO were consistent across all pre-specified patient subgroups, including in patients with or without central nervous system (CNS) metastases. Overall survival data were not mature at the time of the final PFS analysis.

 

Osimertinib was previously approved for use as second line therapy in patients who had progressed on a TKI treatment or for those whose tumors developed a T790M mutation confering resistance to the first generation TKI therapies.

Osimerinibs mechanism of action is thought to be irreversible binding to the EGFR receptor.  Perhaps this explains the improvement in PFS compared to other TKIs. These findings are potentially practice changing.

Despite these impressive improvements in PFS almost all patients eventually fail targeted therapies with TKI agents. Consequently more work is needed to understand the biological mechanisms of resistance and progression in lung cancer patients to enable more effective therapies to be developed.

https://www.onclive.com/web-exclusives/fda-approves-frontline-osimertinib-for-nsclc

Loxo Oncology work with Illumina to develop Cdx NGS assay for Larotrectinib (NTRK) and LOXO-292 (RET)

Anthony Magliocco MD

In an important announcement Industry sequencing leader Illumina and LOXO Oncology, released that they are working on developing a companion diagnostic for larotrectinib, a NTRK inhibitor and LOXO-292 which targets ret.

 

It appears that they intend to use the TST170 as a basis and perhaps a DX version of the Nexseq 500

This is an important development for 2 reasons. The first is the molecular alterations in question are relatively rare, but they can occur in any tumor type regardless of the tissue of origin. The second is the identification of a standard instrument platform and multi-gene assay panel that is already in clinical use (Moffitt has recently deployed a version of TST170 for patient care as Moffitt STAR) will undoubtedly expedite the capability to scale this test for widespread deployment accross laboratories

The fact that TST170 is so comprehensive potentially offers the opportunity for other oncology drug developers to consider using this versatile assay as a companion diagnostic as well.

https://ir.loxooncology.com/press-releases/loxo-oncology-and-illumina-to-partner-on-developing-next-generation-sequencing-based-pan-cancer-companion-diagnostics

STAMFORD, Conn. and SAN DIEGO, April 10, 2018 (GLOBE NEWSWIRE) —  Loxo Oncology (Nasdaq:LOXO) and Illumina, Inc. (Nasdaq:ILMN) today announced a global strategic partnership to develop and commercialize a multi-gene panel for broad tumor profiling, resulting in a distributable, next-generation sequencing (NGS) based companion diagnostic (CDx) with a pan-cancer indication. The co-development partnership will seek approval for a version of the Illumina TruSight Tumor 170 as a companion diagnostic (CDx) for Loxo Oncology’s larotrectinib, which targets NTRK gene fusions, and LOXO-292, which targets RET gene alterations, across tumor types.

TruSight Tumor 170 is a comprehensive, state-of-the-art, next-generation sequencing test that interrogates point mutations, fusions, amplifications and splice variants in 170 genes associated with common solid tumors. The CDx version of TruSight Tumor 170 will allow local laboratories to provide referring physicians with comprehensive genomic information, so that patients can be matched to the most appropriate therapeutic options. This version of TruSight Tumor 170 will run on the NextSeq 550Dx platform.

“We are leveraging our leadership in next-generation sequencing to deliver in-vitro diagnostic solutions to improve the management of cancer patients in the clinic,” said Garret Hampton, Ph.D., executive vice president of clinical genomics at Illumina. “To this end, we are partnering with leading biotechnology companies, such as Loxo Oncology, to develop companion diagnostics for best-in-class therapeutics. Distributable diagnostic solutions, such as a CDx version of TruSight Tumor 170, in combination with the NextSeq 550Dx platform, will enable labs to perform precision medicine testing in-house.”

Under the partnership, the companies will collaborate to validate a CDx version of TruSight Tumor 170 for NTRK fusions and RET fusions/mutations as a Class III FDA-approved diagnostic in conjunction with larotrectinib and LOXO-292, respectively. The companies are also planning to broaden the clinical utility of the full panel by obtaining regulatory approval for the other assay content, to be marketed as a tumor profiling test. Illumina will lead regulatory activities related to the Class III plans for NTRK and RET, the Class II plans for the tumor profiling content, and CE marking.

“We are very excited to announce this collaboration with Illumina, the world’s leader in NGS technology,” said Jacob Van Naarden, chief business officer of Loxo Oncology. “We have piloted numerous NGS assays, and the Illumina TruSight Tumor 170 assay has consistently demonstrated robust performance with its assessment of both DNA and RNA, including highly sensitive gene fusion detection. The broad 170-gene assay content has the potential to deliver meaningful insights from a single tumor specimen, identifying patients with NTRK fusions, RET fusions, RET mutations, and many other actionable tumor alterations. Furthermore, we believe that this collaboration will improve patient access to high-quality NGS testing because pathologists will be able to run TruSight Tumor 170 locally and receive reimbursement.”

New Mechanism Involving NFkappaB Drives Metastasis in Cancer with Chromosomal Instability

By Anthony M Magliocco MD

An interesting and important new study recently published in Nature gives new insights into possible targetable molecular mechanism linking chromosomal instability observed in some cancers and progession and metastasis.

https://www.nature.com/articles/nature25432

A subset of cancers develop chromosomal instability via disjunction errors during mitosis. This can lead to highly aneuploid and abnormal karyotypes more prevalent in certain cancers than other. For example, ovarian cancer is notorious for developing a  disrupted and unstable karyotype.

Metastatic Cancer

It appears that chromosomal instability in itself does not promote metastasis, however, in an intriguing observation it was noted that tumors with chromosomal instability also developed micronuclei when under mechanical stress.

These micronuclei are more prone to cytoplasmic rupture. Free DNA in the cytoplasm triggers a non-canonical NFkappaB cascade which may lead to mesenchymal transformation and a propensity to metastasis.

Interestingly cancers with high aneuploidy do not generally develop a high mutational burden such as cancers like melanoma. Nor do they tend to have targetable driver mutations.

“Cytosolic DNA from micronuclear rupture appears to trigger non-cannonical NFKappaB signaling which could lead to tumor metastasis”

 

DNA in the cytoplasm triggers NFKappaB as part of a host response to viral infection, but cancer may subvert this mechanism. In addition,  NFkappaB non-cannonical activation by cytosolic DNA from ruptured micronuclei may lead to a variety of effects immune activation which could assist with tumor metastasis.

These new insights into the consequences of chromosomal instability create opportunities for developing new therapeutic strategies for these types of cancer that lack specific driver mutations and significant neoantigen loads

 

Moffitt Cancer Center Morsani Molecular Lab Researchers Create New Laboratory Test to Better Diagnose Metastatic Bladder Cancer

Moffitt researchers reported the discovery of a new 19 gene expression signature that appears to have value in improving the accuracy of urothelial cancer diagnosis at the USCAP 2018 meeting in Vancouver.

The correct diagnosis of urothelial cancer, especially when metastatic can be very challenging for the surgical pathologist Urothelial carcinoma (UC) can mimic a poorly squamous cell carcinoma (SCC) and it may be difficult to distinguish the two especially in metastatic sites.

Metastatic cancer imaged with PET scan

 

It is important to distinguish the two cancers for proper patient management. These two cancers have an overlapping immunohistochemical profile (both positive for CK5/6, CK7, p63 and p40). GATA3 although relatively specific for UC, can also be expressed in SCC.

It is important to distinguish urothelial carcinoma from other epithelial cancers to ensure proper diagnosis and patient managment

Gene expression analysis is a powerful method that can measure the expression level of thousands of mRNA messages simultaneously in a tissue biopsy specimen. Analysis of data from this technique, when coupled with bioinformatics analysis can produce powerful classification algorithms which could be used in a CLIA laboratory to improve the accuracy of current diagnostic approaches.

Affymetrix chips for rapid gene expression

The Moffitt researchers analyzed 161 UC, 38 head and neck cases, and 268 lung cancer SCC cases from Moffitts Total Cancer Care (TCC) database to create the initial algorithm. The data was collected on the a specially modified HuRSTA chip containing 60607 probe sets covering 26356 genes. An algorithm was developed from the 19 top most differentially expressed genes using principal component analysis (PCA). The PCA model performed at above 98% sensitivity and specificity correctly identifying the histological origin of the specimens on self validation.

PCA analysis separating tumor types using 19 gene signature

The signature was further validated on publicly available external datasets at GEO datasets, with 96 cases of H&N SCC from GSE31056, 18 lung SCCs from GSE10245 and 93 UC from GSE31684, total of 207 cases.This signature correctly identified 112 of the 114 publicly available SCCs with gene data (96 H&N and 16 lung) as SCC and all of 93 publicly available UCs with gene data as UC

The identification of a gene classification algorithm will enable improved classification of these challenging lesions, particularly in the metastatic setting.

The Moffitt investigators will continue to evaluate this new signature and propose to develop it into a routine diagnostic assay. In addition, deeper understanding of the molecular basis of urothelial cancer and how it differs at the molecular level potentially opens new approaches to therapy.

An assay like this could be far superior than classical IHC as the complexity of gene expression will give multiple insights into not only tissue of orign but also other aspects of the cancer biology such as immune status.

Understanding the molecular basis of urothelial cancer will provide insights into novel treatment opportunity

The work was supported by the Moffitt Morsani Molecular Laboratories

Presented at the 2018 USCAP meeting in Vancouver Canada

Gene Biomarker Signature for Distinguishing Urothelial Carcinoma from Squamous Cell Carcinoma. Jasreman Dhillon, MD Yin Xiong, Ph.D. Anthony Magliocco, MD, Soner Altiok, MD, PhD, H. Lee Moffitt Cancer Center, Tampa FL