THE PATIENT WITH CANCER

By Prof.Dr.C.S.VenkateshMBBS

MS(SURGERY)FICS(USA)

Patient with Cancer

Carcinogenesis: It is the process whereby external influences cause cancer

This can be divided into:A. Irritation-in which cells undergo

transformation into a pre-malignant stage.

B. Promotion-in which these cells are induced to form a tumour

Patient with cancer

The agents which cause cancer are termed as carcinogens and many carcinogens that affect humans have been identified.

1. Polycyclic aromatic hydrocarbons,(PAHs);Tobacco smoke, eg; Benzopyrine and 3-methylcholantherene causing Lung

cancer 2.Infective agents such as Human papilloma virus in

causing CA of uterine CX, Viruses in Nasopharyngeal cancer, Burkitt’s Lymphoma, Hepatocellular carcinoma, T-cell leukaemia and Kaposi’s sarcoma

Patient with cancer

Oncogenes; These are actually normal genes which

have become mutated, and transforming viruses ,transfer these genes from a previously infected host

Physico- chemical agents on the other hand cause direct damage to genes with in the cell

Patient with cancer

Diet; may have an important role in carcinogenesis. Heavily cooked meat is rich in heterocyclic amines are powerful carcinogens

High vegetable intake in contrast is associated with low rates of cancer.Both vegetables and fruits are rich in antioxdants and this may have protective effect,eg;Brocoli,Brussel sprouts

Patient with cancer

Diet and energy intake: There is a positive association between obesity and cancer and a negative association between excercise and cancer.

Calorie restriction decreases the rate of cellular division in many tissues as seen in animal studies

Diet may affect cancer incidence by,1.acting as a source of envioremental carcinogens, 2.acting as a source of protective substances and,3. affecting the rate of cellular proliferation

Patient with cancer

Molecular genetics in cancer Tumorogenesis is a multi step process

that evolves as a result of the accumulation of a number of genetic mutations.

Two major categories of genes involved in tumorogenesis are: ONCOGENES and TUMOUR SUPRESSOR GENES

Patient withCancer

Cancer may present clinically with symptoms and signs of:

1.the primary tumour- with mass,obstruction,bleeding

2,spread to the regional lymph nodes 3,spread by the blood stream-metastasis to

brain,lungs,liver and bone 4,Nonspcific effects-

tiredness,malaise ,LOW,LOAetc 5,Paraneoplastic syndromes-neuropathy,skin

problems,anaemia eg Renal cell carcinoma

Patient with cancer

B.Pathgenesis : Abnormal motility of these malignant cells

C.Breakdown of extracellular matrix Malignat tumours can be defined by their ability

to invade locally and to metastasise to distant organs.

Invasion is thought to be due to combination of: a.Increased pressure produced by rapidly

dividing cells b.Abnormal motility of these malignant cells c.Breakdown of the extracellular matrix by factors

produced by the tumour cells

Patient with Cancer Predominant tumours metastsising to liver lung and bone Site of primary Common sites of Mets Lung Bones,Liver Lung Colon Liver Rectum Liver ,lung Breast Liver Lung and Bone Prostate Bone Ovary Liver, lung Stomach Liver Pancreas Liver Head and Neck Lung Thyroid Bone Urogenital Tract Lung Bladder Liver,lung Bone Melanoma Liver, lung

Patient with cancer

Clinicopathological staging is essential for 3 main reasons:

a, It gives an estimate of the prognosis

B ,Useful in planning treatment

c, Allows estimation of casemix which is vital for interpretation of data and comparison of results from different centres

,

Patient with Cancer

Histological diagnosis requires biopsy. Types of biopsy: Incisional biopsy- for tumours deemed

inoperable Core needle biopsy-Ca breast Endoscopic biospy forGI cancers Fine Needle Aspiration Biopsy(FNAB) Excisional biopsy

Patient with Cancer

TNM Classification –which has been adopted by UICC(Union Internationale Contre le Cancer)

Tumour, Node & Metastasis T-extent of spread N-extent of spread to the lymph nodes M-the presence or absence of metastasis

Patient with cancer

Screening for Cancer involves detection of disease in asymtomatic population in order to improve outcomes by early dignosis eg; Screenig for FAP gene in Colorectal carcinoma,BRCA 1&2 in Cancer Breast, PSA estimation to detect Prostatic cancer etc.

Screening test must be safe,acceptable to the population, relatively cheap,sensitive and Spcific

Patient with Cancer

Needs Compassion Competent and Committed staff Results are excellent if cancers are

diagnosed early. All efforts must be aimed at early

diagnosis

Patient with cancer

Multidisciplinary team in cancer treatment The team comprises of surgeons

oncologists, pathologists, radiologists, and often specialist nurses

The core team must maintain good communication with primary care, palliative care and rehabilitation services

Patient with Cancer

Histological grading is is also important as it carries prognostic significance and may be complementory to TNM staging

Most tumours are subdivided into: Well-differentiated Moderately differentiated Poorly differentiated depending on

Pleomorphism of cells and attempts at gland formation as in adenocarcinomas

Patient with cancer

Surgery; The main aim of cancer surgery is local

control Local control equates to cure when the

disease is localised Surgery can be diagnostic, curative,

palliattive or reconstructive

Patient with Cancer

Laparoscopy- is widely used for staging of intra-abdominal malignancy particularly oesophageal and gastric cancer. It is often possible to diagnose widespread peritoneal disease and small liver metastasis which may have been missed in cross-sectional imaging by lapparoscpy.Laparoscopic ultrasound is particularly useful for diagnosing intrahepatic metastasis

Patient with cancer

Role of Surgery in other cancers : eg:Orchidectomy for carcinoma of testis, and lymph node biopsy in patients with lymphoma

Recently sentinel node biopsy in Melanoma and Breast cancer has attracted a great deal of interest

Patient with cancer

Removal of primary disease Radical surgery for cancer involves

removal of the primary tumour and as much of the surrounding tissue and lymph nodes in order to achieve local control but also to prevent spread of tumour through lymphatics. At least 2cms healthy tumour free margin must be ensured in curative surgery.

Patient with Cancer

Palliation: In many cases Surgery may not be curative: eg a patient with symptomatic primary tumour who has a distant metastasis. Removal of the primary tumour may increase the patient’s quality of life although it will have little effect on the ultimate outcome. Examples of palliative surgery are: By pass procedures on Cancer head of pancreas causing obstructive jaundice or cancer stomach.

Patient with cancer

Surgery for prevention- there are some clear indications for surgery in the prevention of cancer eg: Panproctocolectomy with or without an ileal pouch for a patient with FAP will prevent the development of colorectal cancer which otherwise will be inevitable

Colectomy advised for a patient with ulcerative colitis who has high grade dysplasia on biopsy

Bilateral mastectomy is also recommended for lobular carcinoma in situ which is sometimes requested by the pt with a strong family h/o breast cancer

Patient with cancer

Reconstruction-After surgical excision of solid tumour reconstruction is an integral part of an operation.eg;Reconstruction of the breast after mastectomy, or after head and neck surgery or restoration of the continuity of the gut after resection of gut tumour

Patient with cancer

Radiotherapy: Modern radiotherapy is delivered in the form of

megavoltage X-rays or gamma rays which generate high energy <1.10x6V

Advantages are: 1,Deep seated tumours can be treated 2,Absorption of radiation is similar in all tissues Lower energy X-rays may be used to treat skin

cancers and may be of value in palliation

Patient with Cancer

Chemotherapy- acts at a molecular level They may be in the form of Alkylating agents

eg;Cyclophosphamide, nitrogen mustard-bind to proteins or DNA

Anti metabolites,eg:5-Flurouracil, methtrexate,6-mercaptopurine-induce celldeath or prevent replication

Vinca alkaloids,eg: vinblastine and vincristin-arrest cell mitosis

Patient with Cancer

Antibiotics –Adrimycin,bleomycin,actinomycinD. MitomycinD

They bind the double stranded DNA and prevent replication

Patient with cancer

Hormone Therapy: Some types of cancer notably of

Breast,Endometrium,Prostate are hormone sensitive

They exert their activity on cells by means of blocking the receptors which bind the hormone.Steroid hormones bind cytoplasmic receptors.Peptide hormones bind to receptors that are integral to the cell membrane resulting in transcription and translocation

Patient with Cancer

Immunotherapy- based on the concept that cancer cells might be specifically antigenic or immune response is diminished in cancer pts

BCG ,Cornibacterium or levamisole Interferrons –gamma has been shown to

have anti tumour activity and is used widely in some of the uncommon leukaemias

Patient with cancer

Gene therapy -introducing a gene into cancer cells. Trials are on using a vector such as a retro virus or an adeno virus. Results are promising but not well substantiated.

Biological modifiers show great promise both as single and in combination with conventional chemotherapy. eg:Metallproteinase inhibitors, Epidermal growth factor(EFG)receptor antagonists and cyclin-dependent kinase(CDK) inhibitors

Patient with cancer

In summary: Cancers are curable if detcted early Every effort must be made by the clinicians to

diagnose cancer early. Treatment involves multi disciplinary team effort

by dedicated team of specialists Tender loving care can make world of difference

for a cancer patient

Patient with cancer

The author has successfully recovered from Cancer of the left maxillary antrum after having undergone radical maxillectomy surgery with neck disection followed by radio therapy and chemotherapy.

You may contact the author by email at -

drcsvenkatesh@gmail.com

© 2007-08 Dr C S Venkatesh. All Rights reserved.

Professor of Surgery, University Kuala Lumpur – Royal College of Medicine, Perak. IPOH Malaysia