What is Cancer? Understanding the basics of

Transcription

1 What is Cancer? Understanding the basics of

2 A process of physical and biological changes that occur when normal healthy cells are transformed into cancer cells

3 What is Cancer? Cancer is an umbrella term Describes a collection of diseases that share common features and characteristics Estimated there are more than 200 types of cancer Wide diversity of types of cell in the body each has the potential to develop into a cancer

4 Incidence The number of people who have, or have had cancer Those who are most likely to be affected The most commonly occurring cancers

5 CANCER in UK - Incidence Effects 1 in 2 50% of all cancer cases in the UK are diagnosed in people aged 70 and over. Cancer relatively rare in children less than 1%. 2 nd most common cause of death I in 4 deaths is caused by cancer 4 in 10 cancer cases in the UK are linked with lifestyle choices Worldwide population 6 billion 14.1 million new cases worldwide cancer (CR UK 2012) 8.2 million deaths (CR UK 2012) Will rise to 20 million by 2020 with 12 million deaths

6 Incidence stats What are the top ten cancers for incidence in men?

7 3 most common cancers in men (2015)

8 Most common cancers in men (2015)

9 Incidence stats What are the top ten cancers for incidence in women?

10 3 most common cancers in women

11 Top 10 cancers in women (2015)

12 Most common cancers 2015 (CRUK)

13 Age-Standardised Ten-Year Net Survival, Selected Cancers, Adults (Aged 15-99), England and Wales,

14 Cancer as a chronic disease Chronic diseases Shaped by periods of acute and intensive illness followed by periods of remission People with cancer are living for longer Challenge of living with a chronic, but life threatening illness Challenges the portrayal/ perception of cancer Concept of the survivor having increasing relevance in cancer care

15 Cultural perspectives Images and beliefs surrounding cancer Cancer has a special mystique Given meaning far beyond the rational and biological facts of the disease (Flanagan and Holmes 2000) Negative associations create the context within which patients live with cancer Patients and family have to cope with more than the physical consequences of cancer

16 Cancer biology

17 Healthy Cells

18 Chromosome Each of us has enough DNA to go from here to the Sun and back more than 300 times Or around Earth's equator 2.5 million times!

19 Cell Cycle G 2 Later growth phase M Mitosis S DNA synthesis G 1 Early growth phase G 0 Resting phase

20 Cell Dividing

21 Normal cell growth Carefully controlled process reproduce themselves exactly stop reproducing at the right time stick together in the right place Cell division triggered by the death of a cell Self destruct if they are damaged Cell reproduction and cell death carefully balanced

22 Cell s Dividing

23 Cancer cells are different Cancer cell division is not regulated in the same way as normal cells Cancer cells do not obey signals from other cells Cancer cells do not stick together Cancer cells do not specialise, but stay immature

24 Damaged Gene Cell clock decides when it is time to divide Damaged genes will cause errors in the code and can lead to mutation Specialist genes regulate growth if these are damaged growth may go on uncontrolled More mutational changes can occur causing the cells to look and behave less like the parent cells. DNA Gene A

25 Genetic make up There need to be a number of genetic mutations within a cell before it becomes cancerous An inherited mutation does not mean you will get cancer In some cases an inherited mutation can make it more likely statistically you will develop cancer during your lifetime This is called genetic predisposition

26 Cancer biology Name 14 causes!

27

28 Characteristics of cancer cells Growth Reproduction not subject to the constraints exerted on a normal cell Loss of degree of cell differentiation Mutational differences The ability to spread Loss of contact inhibition Cancer cells loose contact inhibition and continue to divide when they come into contact with other cells Prolonged or indefinite life span Normal cells have a fixed life span and stop dividing or functioning when that point is reached

29 Cancer Cells

30 Growth Doubling time Time it takes for a cancer to double in size 30 times One billion cells (marble size) Can be detected by X- ray or palpation 10 more doublings One trillion Usually the point at which life cannot be sustained For much of its growth cancer is undetectable

31 The rate of growth The rate of growth for different cancers varies greatly from hours to years Cancer growth is often a sustained and constant process rather than a rapid one The characteristics of the parent cell influence the rate of growth static, expanding, renewing

32 However! The rate of growth. Growth is not always a constant process Many cancer cells die Poor blood supply Influence of immune and inflammatory system Unsuccessful mytosis It is unknown whether all cancers grow exponentially throughout their development Some may slow down as they get larger The influence of the doubling time is important but the rate of growth can be more complicated

33 Growth curve for cancer Lethal limit Treatment Limit of detection Immune system can handle Cure

34 The degree of cellular differentiation The degree to which the cancer cell resembles the parent cell Well differentiated close resemblance Undifferentiated little or no resemblance Poorly differentiated tend to divide more frequently and spread more easily

35 Normal breast tissue Well differentiated Poorly differentiated

36 The ability to spread metastases

37

38 Histology - biopsy Needle Incisional Excisional Cytology How do we diagnose? Tissue scrapings Body secretions Body fluids Used to determine tumour type and grade Grade classification based on cellular differentiation Higher the grade less differentiated

39 Tests and investigations X Ray Blood tests Bone marrow Bone scan CT scan Cystoscopy Endoscopy Lumber puncture MRI PET Ultrasound

40 Classifying cancers Generally they are classified according to the type of tissue from which they arose Epithelial Cells - Carcinoma Squamous cell carcinoma Glandular cells e.g kidney cells, breast lung Adenocarcinoma Stretchy cells called transitional cells e.g. the lining of the bladder Transitional cell carcinoma

41 Connective Tissue Sarcomas Cartilage - chondrosarcoma Bone - osteosarcoma Muscle rhabdomyosarcoma

42 Cancer of the blood and Lymph Tissues Cancers of the blood cells - leukaemia's Cancers of the lymphatic system - lymphomas Other cells can become cancerous although these are rare e.g. gliomas

43 Tumour Markers Tumour markers are substances found in the blood, urine, stool and other bodily fluids or tissues of some patients with cancer (these can be proteins, antigens, hormones, enzymes or genes) Tumour markers may be used to help cancer diagnosis Can predict a patients response to treatment

44 Role of staging Staging Give appropriately planned treatment Determine best estimate of prognosis Facilitate comparison of treatment results Assist in the evaluation of results from research

45 Staging TNM systems are grouped into classifications called stages Most proceed form stage 1 to 4 with prognosis worsening for stage progression Stage 1 is generally confined to the tissue of origin Stage 4 is generally metastatic

46 Staging TNM T = size, extent and depth of primary tumour N = presence or absence of involved lymph nodes and size and number of lymph nodes involved M = presence of absence of metastases

47 Treatment What do we need to know about cancer before we can treat it? Size Has it moved from the tissue of origin Has it spread Where has it spread Are there any lymph nodes involved How many lymph nodes