Cancer Oncology | Precision Health Network

Abstract

Modern Cancer Science

Cancer is a group of diseases characterized by uncontrolled cell growth, abnormal proliferation, tissue invasion, and metastasis. Advances in molecular biology, genomics, immunology, and precision medicine are reshaping diagnosis and treatment.

Cell Biology

Abnormal Growth

Cancer cells disable normal controls over growth, division, differentiation, and programmed cell death.

Care

Multimodal Treatment

Modern oncology combines surgery, radiation, chemotherapy, targeted therapy, immunotherapy, hormone therapy, and cellular therapies.

Future

AI and Precision Oncology

AI, liquid biopsy, gene editing, and personalized vaccines are accelerating earlier detection and more individualized treatment.

Parts I-II

Cellular & Molecular Basis of Cancer

Cancer is fundamentally a disease of altered DNA, driven by mutations in oncogenes, tumor suppressors, and genome stability pathways.

Growth

Healthy cells proliferate only in response to regulated physiological signals.

Division

Normal mitosis maintains tissue homeostasis and prevents uncontrolled expansion.

Differentiation

Cells specialize into tissue-specific functional types with defined roles.

Programmed Cell Death

Apoptosis removes damaged or unwanted cells before they threaten tissue health.

Point Mutations

Single nucleotide substitutions can alter protein function, such as KRAS G12D activation.

Insertions / Deletions

Frameshift mutations disrupt open reading frames and often inactivate tumor suppressors.

Rearrangements

Translocations can create fusion oncoproteins such as BCR-ABL in chronic myeloid leukemia.

Copy Number Variants

Amplifications or deletions alter dosage-sensitive regulators such as HER2, MYC, PTEN, and CDKN2A.

KRAS

Drives proliferation through MAPK and PI3K pathways in pancreatic, lung, and colorectal cancer.

MYC

Amplifies cell growth programs and accelerates cell-cycle entry in lymphoma, breast, and lung cancer.

BRAF

V600E activates the MEK-ERK cascade and can be targeted by BRAF inhibitors.

HER2

RTK amplification drives PI3K/AKT signaling and is targeted by HER2-directed therapies.

TP53

The guardian of the genome triggers DNA repair and apoptosis in response to cellular stress.

RB1

Controls the G1-S checkpoint; loss allows unrestrained cell-cycle progression.

BRCA1/2

Support homologous recombination repair; germline mutations increase hereditary breast and ovarian cancer risk.

APC

Regulates Wnt signaling and often initiates the colorectal adenoma-carcinoma sequence when lost.

Part III

Hallmarks of Cancer

The hallmarks framework describes the defining biological capabilities acquired during malignant transformation.

Sustained Proliferative Signaling

Cancer cells generate their own growth signals or become hypersensitive to mitogenic stimulation.

Evasion of Growth Suppressors

Checkpoint pathways such as RB and TP53 are disabled, allowing excessive proliferation.

Resistance to Cell Death

Anti-apoptotic signals allow survival despite severe genomic damage.

Replicative Immortality

Telomerase activation allows cancer cells to bypass normal limits on cell division.

Angiogenesis

Tumors recruit blood vessels through VEGF and related pathways to support continued growth.

Invasion and Metastasis

Cancer cells acquire motility, invade tissues, and seed distant metastatic niches.

Immune Evasion

Checkpoint ligands, suppressive cells, and tumor microenvironments weaken anti-tumor immunity.

Tumor-Promoting Inflammation

Chronic inflammation supplies growth factors, survival signals, and angiogenic support.

Part IV

Major Cancer Types

Common malignancies differ in incidence, molecular subtypes, risk factors, treatment approaches, and screening recommendations.

BC

Breast Cancer

2.3M new cases per year

Breast cancer includes HR+/HER2-, HER2+, triple-negative, lobular, and ductal subtypes. Care may include surgery, radiation, hormone therapy, HER2-targeted therapy, chemotherapy, CDK4/6 inhibitors, and immunotherapy.

Key considerations

BRCA1/2 mutations, estrogen exposure, obesity, alcohol, dense breast tissue, mammography, and MRI for high-risk individuals.

LC

Lung Cancer

Driver-guided therapy

Lung cancer care increasingly relies on molecular testing for EGFR, ALK, ROS1, BRAF, MET, RET, NTRK, PD-L1, and tumor mutational burden.

Precision pathway

Smoking prevention, CT screening in high-risk groups, biopsy, staging, genomic profiling, targeted therapy, immunotherapy, radiation, and surgery when appropriate.

CR

Colorectal Cancer

Screening prevents disease

Colorectal cancer can arise through the adenoma-carcinoma sequence, Lynch syndrome, APC loss, KRAS pathway activation, and microsatellite instability.

Prevention signal

Colonoscopy with polypectomy can prevent many cancers by removing precursor lesions before malignant transformation.

PC

Prostate Cancer

Hormone and genomic risk

Prostate cancer management spans surveillance, surgery, radiation, androgen deprivation therapy, AR pathway inhibitors, radiopharmaceuticals, and PARP inhibitors for selected DNA repair defects.

Clinical focus

Risk stratification combines PSA, imaging, biopsy grade, staging, family history, and molecular biomarkers.

HM

Leukemia, Lymphoma, and Myeloma

Immune and cellular therapies

Blood cancers often use flow cytometry, cytogenetics, NGS, targeted inhibitors, monoclonal antibodies, stem cell transplantation, bispecific antibodies, and CAR-T therapy.

Breakthrough example

BCR-ABL targeted therapy in CML transformed a previously fatal disease into a highly manageable condition for many patients.

Part V

Risk Factors & Cancer Prevention

Up to half of cancers are attributable to modifiable risk factors, making prevention one of the strongest tools for lowering the global cancer burden.

Genetic Risk

BRCA1/2 mutations
Lynch syndrome
Li-Fraumeni syndrome
Familial adenomatous polyposis

Lifestyle Risk

Tobacco use
Alcohol consumption
Obesity
Physical inactivity
Poor diet

Environmental Exposures

UV radiation
Air pollution
Asbestos
Radon gas

Infectious Agents

HPV
Hepatitis B and C
H. pylori
Epstein-Barr virus

Prevention Strategies

Smoking cessation
HPV and HBV vaccination
Colorectal screening
Healthy body weight
Physical activity
Sun protection

Part VI

Diagnosis, Staging & Molecular Testing

Accurate diagnosis and staging combine imaging, pathology, biomarkers, and molecular profiling.

Medical Imaging

CT for staging and tumor measurement
MRI for brain, spine, breast, liver, and soft tissue
PET-CT for metastasis and response
Ultrasound for guided biopsy
Mammography for breast screening

Molecular Testing

Next-generation sequencing
IHC for HER2, ER, PR, PD-L1, Ki-67, and MMR
FISH / ISH for amplifications and fusions
Liquid biopsy for ctDNA
TMB / MSI testing

TNM Staging

TNM describes tumor size, lymph node involvement, and metastasis. Stage I is localized, Stage II is larger or regional, Stage III is extensive regional disease, and Stage IV involves distant metastasis.

Parts VII-IX

Treatment, Targeted Therapy & Immunotherapy

Oncology increasingly combines established pillars of care with biomarker-driven targeted treatments and immune therapies.

Surgery

Curative resection, cytoreduction, prophylactic surgery, and minimally invasive robotic approaches.

Radiation Therapy

External beam radiation, stereotactic radiosurgery, proton therapy, and brachytherapy.

Chemotherapy

Alkylating agents, antimetabolites, taxanes, vinca alkaloids, and anthracyclines.

Hormone Therapy

SERMs, aromatase inhibitors, androgen deprivation therapy, and LHRH agonists or antagonists.

HER2 Inhibitors

Trastuzumab, pertuzumab, lapatinib, T-DM1, and trastuzumab deruxtecan transformed HER2-positive disease.

EGFR Inhibitors

Erlotinib, gefitinib, osimertinib, and cetuximab target EGFR-driven tumors.

BRAF / MEK Inhibitors

Combination BRAF and MEK blockade delays resistance in BRAF-mutant melanoma and other cancers.

ALK / ROS1 Inhibitors

Crizotinib, alectinib, brigatinib, lorlatinib, and entrectinib target rearranged lung cancers.

PARP Inhibitors

Olaparib, rucaparib, niraparib, and talazoparib exploit synthetic lethality in BRCA-deficient cells.

CDK4/6 Inhibitors

Palbociclib, ribociclib, and abemaciclib improve outcomes in HR-positive breast cancer.

PD-1 Inhibitors

Pembrolizumab and nivolumab release T-cell brakes across melanoma, lung cancer, MSI-H tumors, Hodgkin lymphoma, and other cancers.

PD-L1 Inhibitors

Atezolizumab, durvalumab, and avelumab support treatment in lung, bladder, triple-negative breast, Merkel cell, and liver cancer.

CTLA-4 Inhibitors

Ipilimumab and tremelimumab can enhance immune priming, often in combination with PD-1 pathway blockade.

Kymriah

CD19-directed CAR-T therapy for relapsed or refractory B-ALL and diffuse large B-cell lymphoma.

Yescarta

CD19-directed CAR-T therapy with strong response rates in large B-cell lymphoma.

Carvykti and Abecma

BCMA-directed CAR-T therapies for heavily pretreated multiple myeloma.

Emerging Immunotherapies

Neoantigen vaccines, bispecific T-cell engagers, NK-cell therapies, TIL therapy, oncolytic viruses, and therapeutic cancer vaccines.

Part X

Future Directions in Cancer Research

The next decade of oncology will be shaped by AI, multi-omics, liquid biopsy, personalized vaccines, gene editing, and global cancer equity.

Artificial Intelligence

AI supports melanoma detection, lung nodule analysis, tumor grading, drug discovery, and faster diagnosis.

Multi-Omics Integration

Genomics, transcriptomics, proteomics, and metabolomics create comprehensive cancer portraits.

Early Detection

Multi-cancer early detection blood tests may identify cancer before symptoms appear in high-risk populations.

Personalized Vaccines

mRNA neoantigen vaccines encode patient-specific tumor mutations to induce durable anti-tumor immunity.

Gene Editing

CRISPR-based approaches can enhance CAR-T manufacturing and may eventually target tumor cells directly.

Global Cancer Equity

Scalable diagnostics, affordable biosimilars, and capacity-building are essential because most deaths occur where access is limited.

References

Scientific Bibliography

1.
Hanahan, D., & Weinberg, R. A. (2011). Hallmarks of Cancer: The Next Generation. Cell, 144(5), 646-674.
2.
Hanahan, D. (2022). Hallmarks of Cancer: New Dimensions. Cancer Discovery, 12(1), 31-46.
3.
National Cancer Institute. (2024). Cancer Statistics and Treatment Resources. U.S. National Institutes of Health.
4.
American Cancer Society. (2024). Cancer Facts & Figures 2024. ACS.
5.
DeVita, V. T., Lawrence, T. S., & Rosenberg, S. A. (2023). Cancer: Principles & Practice of Oncology. Wolters Kluwer.
6.
Vogelstein, B., Papadopoulos, N., Velculescu, V. E., et al. (2013). Cancer Genome Landscapes. Science, 339(6127), 1546-1558.
7.
Topalian, S. L., Drake, C. G., & Pardoll, D. M. (2015). Immune Checkpoint Blockade. Cancer Cell, 27(4), 450-461.
8.
June, C. H., O'Connor, R. S., Kawalekar, O. U., et al. (2018). CAR T Cell Immunotherapy for Human Cancer. Science, 359(6382), 1361-1365.
9.
Sung, H., Ferlay, J., Siegel, R. L., et al. (2021). Global Cancer Statistics 2020. CA: A Cancer Journal for Clinicians, 71(3), 209-249.
10.
World Health Organization. (2024). Cancer Fact Sheets and Global Cancer Control Resources. WHO.

FAQ

Frequently Asked Questions - Cancer & Oncology

Evidence-based answers to common questions about cancer biology, diagnosis, precision oncology, and immunotherapy.

What causes cancer at the molecular level?

Cancer arises when genetic and epigenetic changes activate oncogenes, disable tumor suppressors, impair DNA repair, and allow cells to proliferate, survive, invade, and evade immune control.

What are the hallmarks of cancer?

Hallmarks include sustained proliferation, growth suppressor evasion, resistance to cell death, replicative immortality, angiogenesis, invasion, metastasis, inflammation, and immune evasion.

What is immunotherapy for cancer?

Immunotherapy uses the immune system to recognize and attack cancer, including checkpoint inhibitors, CAR-T cells, bispecific antibodies, vaccines, and tumor-infiltrating lymphocyte therapy.

What is precision oncology?

Precision oncology matches tumor molecular profiles to targeted treatments, immunotherapy markers, clinical trials, and individualized care strategies.

How is cancer diagnosed using AI and genomics?

AI analyzes radiology, pathology, EHR, and molecular data, while genomics identifies driver mutations, resistance patterns, hereditary risk, and biomarkers for targeted therapy.