BIO 302 - Exam 3 - Cancer Diagnosis & Assessment PowerPoint pt.2

Question 1

Recap of phases of the natural history of cancer development:
Preclinical phase: No signs or symptoms of cancer
Mean time is 8-20 years
As short as a few months (Burkitt lymphoma)
As long as 30-40 years
Clinical phase begins at the point when the cancer is diagnosed.
This phase occupies only 25% of the natural history of the cancer.
At this point, an attempt to cure or palliate the patient with cancer
If the cancer is not eradicated at this point the patient will die

Question 2

Prognosis is a ______ whereas a diagnosis is a present ______.

Answer 2

prediction / fact

Question 3

Determining prognosis

Medical prediction is typically based on statistical averages from populations of patients with comparable disease features
For any GIVEN patient, the prediction is most often imprecise
Example: For stage II colon cancer, complete surgical excision is curative for 80% of patients; an individual patient wants to know if they are one of the 80% or not!
More individualized prognosis depends on algorithms and mathematical calculation that includes ALL prognostic factors for a specific patient.

Question 4

Estimating individualized prognosis: computational medicine

Influenced by a multitude of factors
“Prognostic factors”
Factors may increase (favorable or positive factors) or decrease (negative or adverse factors) the likelihood of survival
Prognostic factor types
Those related to the disease
Those related to the patient
Those related to the medical environment

Question 5

tumor-related Prognostic factors

Tumor type or subtype
Tumor grade
Tumor stage (a dominant factor)
Presence of specific invasion patterns:
Venous invasion
Lymphatic invasion
Peri-neural invasion
Where the tumor is located (anatomic location and adjacencies)
Specific pathological or molecular features
Presence of abnormal chromosomes
Presence of mutations or mutated proteins or the over-expression of normal oncogenic proteins
HER2 over-expression in breast cancer is an adverse “prognostic” factor but a favorable “predictive” factor for response to Herceptin targeted therapy

Question 6

patient-related Prognostic factors

Patient’s age
Patient’s gender
Patient’s overall condition (“performance score”)
Presence of other medical conditions (“co-morbidities”)
Function of vital organs
Presence of cancer-specific symptoms:
Weight loss
Pain
Fever

Question 7

Performance status: a “systems” level measurement

ECOG scale vs. Karnofsky scale

Question 8

Care environment-related Prognostic factors

Socioeconomic conditions and healthcare policies of the region (country, state, etc.)
Availability of oncology care in local region
Track record of the treatment institution for the specific disease
Measured in outcomes for patients
Patient volume in the institution
Degree of experience of the surgeon
Degree of experience of the oncology “team”
Use of a standard of care treatment plan
Validity and performance status of the diagnostic tests

Question 9

Take home messages (1)

The correct diagnosis is essential for accurate prognosis and correct treatment.
Symptoms and signs of cancer may point to the site/source of the cancer but may be non-specific.
Definitive diagnosis typically requires the use of techniques that examine tumor cells directly (cytology or biopsy).
Imaging studies are essential for establishing the exact anatomic location, configuration, and structural adjacencies of the primary tumor.
Imaging studies are the primary basis for establishing clinical stage of the tumor.
Imaging modalities that use ionizing radiation such as X-rays and computerized axial tomography (CAT or CT scans) present a risk of mutation in DNA of normal cells.
Magnetic resonance imaging (MRI) has no mutation-inducing capacity.

Question 10

Take home messages (2)

Prognosis is the prediction of future outcome from the disease: specially, the risk of dying from the cancer.
Prognosis is influenced by factors related to the tumor, the patient, and the medical environment.
“Predictive factor” is the term used to describe factors that are related to the likelihood of response to a specific therapy.
The dominant prognostic factor for the majority of carcinomas is stage.
Molecular testing may be done for a cancer for different reasons: diagnosis, prognosis, or prediction of therapeutic response.
Multidisciplinary teams are required for the best cancer care!