Machine learning in oral squamous cell carcinoma: current status, clinical concerns and prospects for future-A systematic review

Background: Oral cancer can show heterogenous patterns of behavior. For proper and effective management of oral cancer, early diagnosis and accurate prediction of prognosis are important. To achieve this, artificial intelligence (AI) or its subfield, machine learning, has been touted for its potential to revolutionize cancer management through improved diagnostic precision and prediction of outcomes. Yet, to date, it has made only few contributions to actual medical practice or patient care. Objectives: This study provides a systematic review of diagnostic and prognostic application of machine learning in oral squamous cell carcinoma (OSCC) and also highlights some of the limitations and concerns of clinicians towards the implementation of machine learning-based models for daily clinical practice. Data sources: We searched OvidMedline, PubMed, Scopus, Web of Science, and Institute of Electrical and Electronics Engineers (IEEE) databases from inception until February 2020 for articles that used machine learning for diagnostic or prognostic purposes of OSCC. Eligibility criteria: Only original studies that examined the application of machine learning models for prognostic and/or diagnostic purposes were considered. Data extraction: Independent extraction of articles was done by two researchers (A.R. & O.Y) using predefine study selection criteria. We used the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) in the searching and screening processes. We also used Prediction model Risk of Bias Assessment Tool (PROBAST) for assessing the risk of bias (ROB) and quality of included studies. Results: A total of 41 studies were published to have used machine learning to aid in the diagnosis/or prognosis of OSCC. The majority of these studies used the support vector machine (SVM) and artificial neural network (ANN) algorithms as machine learning techniques. Their specificity ranged from 0.57 to 1.00, sensitivity from 0.70 to 1.00, and accuracy from 63.4 % to 100.0 % in these studies. The main limitations and concerns can be grouped as either the challenges inherent to the science of machine learning or relating to the clinical implementations. Conclusion: Machine learning models have been reported to show promising performances for diagnostic and prognostic analyses in studies of oral cancer. These models should be developed to further enhance explainability, interpretability, and externally validated for generalizability in order to be safely integrated into daily clinical practices. Also, regulatory frameworks for the adoption of these models in clinical practices are necessary.Peer reviewe

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 prognostic value of CT radiomic features from primary tumours and pathological lymph nodes in head and neck cancer patients

Head and neck cancer (HNC) is responsible for about 0.83 million new cancer cases and 0.43 million cancer deaths worldwide every year. Around 30%-50% of patients with locally advanced HNC experience treatment failures, predominantly occurring at the site of the primary tumor, followed by regional failures and distant metastases. In order to optimize treatment strategy, the overall aim of this thesis is to identify the patients who are at high risk of treatment failures. We developed and externally validated a series of models on the different patterns of failure to predict the risk of local failures, regional failures, distant metastasis and individual nodal failures in HNC patients. New type of radiomic features based on the CT image were included in our modelling analysis, and we firstly showed that the radiomic features improved the prognostic performance of the models containing clinical factors significantly. Our studies provide clinicians new tools to predict the risk of treatment failures. This may support optimization of treatment strategy of this disease, and subsequently improve the patient survival rate

Diagnosis and Prognosis of Head and Neck Cancer Patients using Artificial Intelligence

Cancer is one of the most life-threatening diseases worldwide, and head and neck (H&N) cancer is a prevalent type with hundreds of thousands of new cases recorded each year. Clinicians use medical imaging modalities such as computed tomography and positron emission tomography to detect the presence of a tumor, and they combine that information with clinical data for patient prognosis. The process is mostly challenging and time-consuming. Machine learning and deep learning can automate these tasks to help clinicians with highly promising results. This work studies two approaches for H&N tumor segmentation: (i) exploration and comparison of vision transformer (ViT)-based and convolutional neural network-based models; and (ii) proposal of a novel 2D perspective to working with 3D data. Furthermore, this work proposes two new architectures for the prognosis task. An ensemble of several models predicts patient outcomes (which won the HECKTOR 2021 challenge prognosis task), and a ViT-based framework concurrently performs patient outcome prediction and tumor segmentation, which outperforms the ensemble model.Comment: This is Masters thesis work submitted to MBZUA

Medical Image Analytics (Radiomics) with Machine/Deeping Learning for Outcome Modeling in Radiation Oncology

Image-based quantitative analysis (radiomics) has gained great attention recently. Radiomics possesses promising potentials to be applied in the clinical practice of radiotherapy and to provide personalized healthcare for cancer patients. However, there are several challenges along the way that this thesis will attempt to address. Specifically, this thesis focuses on the investigation of repeatability and reproducibility of radiomics features, the development of new machine/deep learning models, and combining these for robust outcomes modeling and their applications in radiotherapy. Radiomics features suffer from robustness issues when applied to outcome modeling problems, especially in head and neck computed tomography (CT) images. These images tend to contain streak artifacts due to patients’ dental implants. To investigate the influence of artifacts for radiomics modeling performance, we firstly developed an automatic artifact detection algorithm using gradient-based hand-crafted features. Then, comparing the radiomics models trained on ‘clean’ and ‘contaminated’ datasets. The second project focused on using hand-crafted radiomics features and conventional machine learning methods for the prediction of overall response and progression-free survival for Y90 treated liver cancer patients. By identifying robust features and embedding prior knowledge in the engineered radiomics features and using bootstrapped LASSO to select robust features, we trained imaging and dose based models for the desired clinical endpoints, highlighting the complementary nature of this information in Y90 outcomes prediction. Combining hand-crafted and machine learnt features can take advantage of both expert domain knowledge and advanced data-driven approaches (e.g., deep learning). Thus, we proposed a new variational autoencoder network framework that modeled radiomics features, clinical factors, and raw CT images for the prediction of intrahepatic recurrence-free and overall survival for hepatocellular carcinoma (HCC) patients in this third project. The proposed approach was compared with widely used Cox proportional hazard model for survival analysis. Our proposed methods achieved significant improvement in terms of the prediction using the c-index metric highlighting the value of advanced modeling techniques in learning from limited and heterogeneous information in actuarial prediction of outcomes. Advances in stereotactic radiation therapy (SBRT) has led to excellent local tumor control with limited toxicities for HCC patients, but intrahepatic recurrence still remains prevalent. As an extension of the third project, we not only hope to predict the time to intrahepatic recurrence, but also the location where the tumor might recur. This will be clinically beneficial for better intervention and optimizing decision making during the process of radiotherapy treatment planning. To address this challenging task, firstly, we proposed an unsupervised registration neural network to register atlas CT to patient simulation CT and obtain the liver’s Couinaud segments for the entire patient cohort. Secondly, a new attention convolutional neural network has been applied to utilize multimodality images (CT, MR and 3D dose distribution) for the prediction of high-risk segments. The results showed much improved efficiency for obtaining segments compared with conventional registration methods and the prediction performance showed promising accuracy for anticipating the recurrence location as well. Overall, this thesis contributed new methods and techniques to improve the utilization of radiomics for personalized radiotherapy. These contributions included new algorithm for detecting artifacts, a joint model of dose with image heterogeneity, combining hand-crafted features with machine learnt features for actuarial radiomics modeling, and a novel approach for predicting location of treatment failure.PHDApplied PhysicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/163092/1/liswei_1.pd

Pancreatic Cancer - Early Detection, Prognostic Factors, and Treatment

Background: Pancreatic cancer is the fourth leading cause of cancer-related death. Only about 6% of patients are alive 5 years after diagnosis. One reason for this low survival rate is that most patients are diagnosed at a late stage, when the tumor has spread to surrounding tissues or distant organs. Less than 20% of cases are diagnosed at an early stage that allows them to undergo potentially curative surgery. However, even for patients with a tumor that has been surgically removed, local and systemic recurrence is common and the median survival is only 17-23 months. This underscores the importance to identify factors that can predict postresection survival. With technical advances and centralization of care, pancreatic surgery has become a safe procedure. The future optimal treatment for pancreatic cancer is dependent on increased understanding of tumor biology and development of individualized and systemic treatment. Previous experimental studies have reported that mucins, especially the MUC4 mucin, may confer resistance to the chemotherapeutic agent gemcitabine and may serve as targets for the development of novel types of intervention. Aim: The aim of the thesis was to investigate strategies to improve management of pancreatic cancer, with special reference to early detection, prognostic factors, and treatment. Methods: In paper I, 27 prospectively collected serum samples from resectable pancreatic cancer (n=9), benign pancreatic disease (n=9), and healthy controls (n=9) were analyzed by high definition mass spectrometry (HDMSE). In paper II, an artificial neural network (ANN) model was constructed on 84 pancreatic cancer patients undergoing surgical resection. In paper III, we investigated the effects of transition from a low- to a high volume-center for pancreaticoduodenectomy in 221 patients. In paper IV, the grade of concordance in terms of MUC4 expression was examined in 17 tissue sections from primary pancreatic cancer and matched lymph node metastases. In paper V, pancreatic xenograft tumors were generated in 15 immunodeficient mice by subcutaneous injection of MUC4+ human pancreatic cancer cell lines; Capan-1, HPAF-II, or CD18/HPAF. In paper VI, a 76-member combined epigenetics and phosphatase small-molecule inhibitor library was screened against Capan-1 (MUC4+) and Panc-1 (MUC4-) cells, followed by high content screening of protein expression. Results/Conclusion: 134 differentially expressed serum proteins were identified, of which 40 proteins showed a significant up-regulation in the pancreatic cancer group. Pancreatic disease link associations could be made for BAZ2A, CDK13, DAPK1, DST, EXOSC3, INHBE, KAT2B, KIF20B, SMC1B, and SPAG5, by pathway network linkages to p53, the most frequently altered tumor suppressor in pancreatic cancer (I). An ANN survival model was developed, identifying 7 risk factors. The C-index for the model was 0.79, and it performed significantly better than the Cox regression (II). We experienced improved surgical results for pancreaticoduodenectomy after the transition to a high-volume center (≥25 procedures/year), including decreased operative duration, blood loss, hemorrhagic complications, reoperations, and hospital stay. There was also a tendency toward reduced operative mortality, from 4% to 0% (III). MUC4 positivity was detected in most primary pancreatic cancer tissues, as well as in matched metastatic lymph nodes (15/17 vs. 14/17), with a high concordance level (82%) (IV). The tumor incidence was 100% in the xenograft model. The median MUC4 count was found to be highest in Capan-1 tumors. α-SMA and collagen extent were also highest in Capan-1 tumors (V). Apicidin (a histone deacetylase inhibitor) had potent antiproliferative activity against Capan-1 cells and significantly reduced the expression of MUC4 and its transcription factor HNF4α. The combined treatment of apicidin and gemcitabine synergistically inhibited growth of Capan-1 cells (VI)