Molecular classification and prediction of metastatic potential in early malignant melanoma: improvement of prognostic accuracy by quantitative in situ proteomic analysis

The incidence of cutaneous malignant melanoma continues to increase every year, and remains the leading cause of skin cancer death in industrialized countries. In spite of the aggressive nature of advanced melanoma, there are no standard biological assays in clinical usage that can predict metastasis. This may be due, in part, to the inadequacy of reproducible assessment of protein expression using traditional immunohistochemistry. This dissertation will discuss the use of tissue microarrays combined with quantitative in situ molecular analysis of protein expression to allow prediction of melanoma metastasis. Through the identification and validation of novel prognostic biomarkers, we seek to identify subsets of patients that are at high or low risk for melanoma recurrence or melanoma-related death. Some of these biomarkers may also serve as potential targets for future biologic therapy in melanoma, a disease for which no effective medical treatment is currently available. We demonstrate that quantitative assessment of a small number of markers is predictive of metastasis and outcome, augmenting the current system of prognosis.The dissertation begins with a brief introduction on the current state of melanoma diagnosis, staging, and treatment, as well as a review of current efforts to understand the biology of melanoma progression and metastasis. The fundamentals of tissue microarray technology are then described. Critical aspects of quantitative immunohistochemistry, including a description of the Automated Quantitative Analysis (AQUA) system developed in our laboratory, are also addressed. The second chapter demonstrates the use of tissue microarray technology to examine melanoma specimens by the current field standard, with a study of activating transcription factor 2 (ATF2); an example of semi-quantitative immunohistochemical analysis of protein expression. The third chapter provides validation of the AQUA technology on melanoma tissue by evaluation of the human homologue of murine double minute 2 protein (HDM2). Chapter four demonstrates an example of the critical--and beneficial--aspect of subcellular compartmentalization that the AQUA system provides, demonstrating that the ratio of cytoplasmic-to-nuclear expression of activator protein 2 (AP-2) predicts outcome in melanoma patients. The last chapter draws these concepts together and presents results from the analysis of 50 protein biomarkers in melanoma. It also introduces the use of a number of statistical methods (traditional and novel) employed to develop an optimal biomarker set for future analyses

Improving biomarker assessment in breast pathology

The accuracy of prognostic and therapy-predictive biomarker assessment in breast tumours is crucial for management and therapy decision in patients with breast cancer. In this thesis, biomarkers used in clinical practice with emphasise on Ki67 and HER2 were studied using several methods including immunocytochemistry, in situ hybridisation, gene expression assays and digital image analysis, with the overall aim to improve routine biomarker evaluation and clarify the prognostic potential in early breast cancer. In paper I, we reported discordances in biomarker status from aspiration cytology and paired surgical specimens from breast tumours. The limited prognostic potential of immunocytochemistry-based Ki67 scoring demonstrated that immunohistochemistry on resected specimens is the superior method for Ki67 evaluation. In addition, neither of the methods were sufficient to predict molecular subtype. Following this in paper II, biomarker agreement between core needle biopsies and subsequent specimens was investigated, both in the adjuvant and neoadjuvant setting. Discordances in Ki67 and HER2 status between core biopsies and paired specimens suggested that these biomarkers should be re-tested on all surgical breast cancer specimens. In paper III, digital image analysis using a virtual double staining software was used to compare methods for assessment of proliferative activity, including mitotic counts, Ki67 and the alternative marker PHH3, in different tumour regions (hot spot, invasive edge and whole section). Digital image analysis using virtual double staining of hot spot Ki67 outperformed the alternative markers of proliferation, especially in discriminating luminal B from luminal A tumours. Replacing mitosis in histological grade with hot spot-scored Ki67 added significant prognostic information. Following these findings, the optimal definition of a hot spot for Ki67 scoring using virtual double staining in relation to molecular subtype and outcome was investigated in paper IV. With the growing evidence of global scoring as a superior method to improve reproducibility of Ki67 scoring, a different digital image analysis software (QuPath) was also used for comparison. Altogether, we found that automated global scoring of Ki67 using QuPath had independent prognostic potential compared to even the best virtual double staining hot spot algorithm, and is also a practical method for routine Ki67 scoring in breast pathology. In paper V, the clinical value of HER2 status was investigated in a unique trastuzumab-treated HER2-positive cohort, on the protein, mRNA and DNA levels. The results demonstrated that low levels of ERBB2 mRNA but neither HER2 copy numbers, HER2 ratio nor ER status, was associated with risk of recurrence among anti-HER2 treated breast cancer patients. In conclusion, we have identified important clinical aspects of Ki67 and HER2 evaluation and provided methods to improve the prognostic potential of Ki67 using digital image analysis. In addition to protein expression of routine biomarkers, mRNA levels by targeted gene expression assays may add further prognostic value in early breast cance

A Pictorial Exploration of Mammary Paget Disease: Insights and Perspectives

Mammary Paget disease (MPD) is a rare condition primarily affecting adult women, characterized by unilateral skin changes in the nipple–areolar complex (NAC) and frequently associated with underlying breast carcinoma. Histologically, MPD is identified by large intraepidermal epithelial cells (Paget cells) with distinct characteristics. Immunohistochemical profiles aid in distinguishing MPD from other skin conditions. Clinical evaluation and imaging techniques, including magnetic resonance imaging (MRI), are recommended if MPD is suspected, although definitive diagnosis always requires histological examination. This review delves into the historical context, epidemiology, pathogenesis, clinical manifestations, and diagnosis of MPD, emphasizing the need for early detection. The classification of MPD based on pathogenesis is explored, shedding light on its varied presentations. Treatment options, including mastectomy and breast-conserving surgery, are discussed with clear guidelines for different scenarios. Adjuvant therapies are considered, particularly in cases with underlying breast cancer. Prognostic factors are outlined, underlining the importance of early intervention. Looking to the future, emerging techniques, like liquid biopsy, new immunohistochemical and molecular markers, and artificial intelligence-based image analysis, hold the potential to transform MPD diagnosis and treatment. These innovations offer hope for early detection and improved patient care, though validation through large-scale clinical trials is needed

Risk factors and biomarkers for metastatic cutaneous squamous cell carcinoma

The incidence of cutaneous squamous cell carcinoma (cSCC), the most common skin cancer with metastatic potential, continues to increase. Although proportion of cSCCs metastasize and cause mortality, sufficient means to identify the metastasis-prone tumors are not available. In this thesis the metastatic cSCCs from the area served by Turku University Hospital were identified and characterized revealing that the rate of metastasis in the study region was 2.3%. Further, it was discovered that metastasis occurs rapidly and that there was no history of cSCC in 85% of patients with metastatic cSCC. Invasion depth, tumor diameter, age and location on lower lip or forehead were associated with increased risk of metastasis. On the other hand, usage of isosorbide mono-/dinitrate and aspirin as well as comorbidity with premalignant lesions or basal cell carcinoma were associated with lower risk of metastasis. With multiplexed immunohistochemistry, it was demonstrated that the activity and phenotype of cancer-associated fibroblasts (CAFs) evolve during the progression of cSCC. Elevation of α-smooth muscle actin (αSMA), secreted protein acidic and rich in cysteine (SPARC) and fibroblast activating protein (FAP) expression was associated with invasion and expression of FAP and platelet-derived growth factor receptor-β (PDGFRβ) with metastasis. High expression of stromal PDGFRβ and periostin were associated with worse prognosis. CAF107 (PDGFRα-/PDGFRβ+/FAP+) subset was associated with invasion and metastasis, and predicted poor prognosis of cSCC. A deep learning algorithm was harnessed to distinguish primary tumors that metastasize rapidly from non-metastatic cSCCs with slide level area under the receiver operating characteristic curve (AUROC) of 0.747 on whole slide images representing primary cSCCs. Furthermore, a risk factor model, that utilized prediction by AI, was created and provided staging systems and comparative risk factor models surpassing classification and prognostivity. These results characterize features associated with the metastasis risk of cSCC and indicate that CAF-markers and AI could provide clinical tools for the metastasis risk assessment and thus improve the prognosis of patient with metastatic cSCC.Etäpesäkkeitä lähettävän okasolusyövän riskitekijät ja biomarkkerit Yleisimmän etäpesäkkeitä lähettävän ihosyövän, okasolusyövän, ilmaantuvuus jatkaa kasvuaan. Vaikka osa okasolusyövistä lähettää etäpesäkkeitä ja aiheuttaa kuolleisuutta, ei etäpesäkkeitä lähettämään tulevien okasolusyöpien tunnistamiseksi ole toistaiseksi riittäviä keinoja. Tässä väitöskirjassa karakterisoitiin Turun yliopistollisen keskussairaalan vastuualueen metastasoituneet okasolusyövät ja osoitettiin että tutkimusalueen okasolusyövistä 2.3% etenee etäpesäkkeitä lähettäväksi. Metastasoituminen tapahtui nopeasti ja valtaosassa tapauksista (85%) etäpesäkkeen lähetti ensimmäinen potilaalla todettu okasolusyöpä. Ikä, kasvaimen invaasiosyvyys, halkaisija ja sijainti alahuulessa tai otsalla yhdistyivät kohonneeseen metastaasiriskiin. Isosorbidinitraatin ja aspiriinin käyttö sekä esiasteiden ja tyvisolusyövän esiintyminen taas liittyivät alentuneeseen metastaasiriskiin. Multiplex-immunohistokemiaa hyödyntäen osoitettin, että syöpään liittyvien fibroblastien (CAF) aktiviteetti ja ilmiasu muuttuu okasolusyövän edetessä. Kohonnut sileälihasaktiini alfan (αSMA), osteonektiinin ja fibroblastia aktivoivan proteiinin (FAP) ilmentyminen liittyi invaasioon ja FAP:n sekä verihiutaleista johdetun kasvutekijäreseptori β:n (PDGFRβ) etäpesäkkeiden lähettämiseen. PDGFRβ:n ja periostiinin ilmentyminen taas yhdistyi huonoon ennusteeseen. CAF107 (PDGFRα-/PDGFRβ+/FAP+) alatyyppi liittyi invaasioon, metastasointiin ja huonoon ennusteeeseen. Etäpesäkkeitä lähettämään tulevien okasolusyöpien tunnistamiseen valjastettu syväoppimisalgoritmi erotti okasolusyöpiä edustavista digitalisoiduista mikroskopiakuvista nopeasti etäpesäkkeitä lähettävät okasolusyövät okasolusyövistä, jotka eivät lähetä etäpesäkkeitä, leiketason AUROC-arvolla 0.747. Tekoälyarviota hyödyntävä riskitekijämalli voitti luokittelujärjestelmät ja kilpailevat riskitekijämallit okasolusyöpien luokittelussa ja ennusteen arvioinnissa. Tulokset antavat lisätietoa metastasoituvan okasolusyövän luonteesta ja osoittavat CAF-markkereiden sekä tekoälyn voivan tarjota kliinisiä työkaluja okasolusyövän metastaasiriskin arviointiin ja täten voivan parantaa etäpesäkkeitä lähettävän okasolusyöpäpotilaan ennustetta tulevaisuudessa

The use of lymphoscintigraphy to localise the sentinel lymph node

Includes bibliographical references (leaves 72-90).Sentinel lymph node (SLN) biopsy is being used increasingly for staging early breast carcinoma in place of complete axillary lymph node dissection. The optimal method to identify the SLN and has not been clearly elucidated in the literature. A number of techniques have been proposed for identifying SLN/s. The main debate centres on whether to use a blue dye or radiopharmaceutical method either singly or in combination

Automated histopathological analyses at scale

Thesis: S.M., Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2017.Cataloged from PDF version of thesis.Includes bibliographical references (pages 68-73).Histopathology is the microscopic examination of processed human tissues to diagnose conditions like cancer, tuberculosis, anemia and myocardial infractions. The diagnostic procedure is, however, very tedious, time-consuming and prone to misinterpretation. It also requires highly trained pathologists to operate, making it unsuitable for large-scale screening in resource-constrained settings, where experts are scarce and expensive. In this thesis, we present a software system for automated screening, backed by deep learning algorithms. This cost-effective, easily-scalable solution can be operated by minimally trained health workers and would extend the reach of histopathological analyses to settings such as rural villages, mass-screening camps and mobile health clinics. With metastatic breast cancer as our primary case study, we describe how the system could be used to test for the presence of a tumor, determine the precise location of a lesion, as well as the severity stage of a patient. We examine how the algorithms are combined into an end-to-end pipeline for utilization by hospitals, doctors and clinicians on a Software as a Service (SaaS) model. Finally, we discuss potential deployment strategies for the technology, as well an analysis of the market and distribution chain in the specific case of the current Indian healthcare ecosystem.by Mrinal Mohit.S.M

Radiomics and artificial intelligence in prostate cancer: new tools for molecular hybrid imaging and theragnostics

In prostate cancer (PCa), the use of new radiopharmaceuticals has improved the accuracy of diagnosis and staging, refined surveillance strategies, and introduced specific and personalized radioreceptor therapies. Nuclear medicine, therefore, holds great promise for improving the quality of life of PCa patients, through managing and processing a vast amount of molecular imaging data and beyond, using a multi-omics approach and improving patients' risk-stratification for tailored medicine. Artificial intelligence (AI) and radiomics may allow clinicians to improve the overall efficiency and accuracy of using these "big data" in both the diagnostic and theragnostic field: from technical aspects (such as semi-automatization of tumor segmentation, image reconstruction, and interpretation) to clinical outcomes, improving a deeper understanding of the molecular environment of PCa, refining personalized treatment strategies, and increasing the ability to predict the outcome. This systematic review aims to describe the current literature on AI and radiomics applied to molecular imaging of prostate cancer