Biology of Disease

PIF/TNF-AZAG

FFAs

FFAs

Amino acids Liver

Skeletal muscle

(proteolysis)

ZAG

ZAG

Tumor

Glucose Lactate

Glucose Lactate

PIF

PIF

Heat

Adipose tissues

(lipolysis)

Free fatty acids

Proteolysis inducing factor

TNF-A Tumor necrosis factorA

ZincA2-glycoprotein

Figure 17.20Molecular model of cachectin
(Tumor Necrosis Factor @). PBD file 1TNF.

Figure 17.21Some of the physiological activities involved in cancer cachexia.

GENERAL DIAGNOSIS OF CANCER

CZhhVg6]bZY!BVjgZZc9Vlhdc!8]g^hHb^i]:YLddY )-.

concentrations should therefore always be followed by further tests, including
physical examination and diagnostic imaging.

Detection and localization of tumors within the body

Patients who present with symptoms indicative of cancer may be examined
using diagnostic imaging procedures in order to localize the potential tumor
or to determine the extent of metastasis. Diagnostic imaging may involve
the use of X-rays, computed tomography (CT) also known as computed axial
tomography (CAT), magnetic resonance imaging (MRI), positron emission
tomography (PET) and ultrasound, all of which are undertaken by clinical
radiologists.

The routine screening for breast cancer by mammography is offered to
women in the UK over the age of 50 years. A tumor will show up as a shadow on
a breast mammogram. Patients who have lung cancer may have X-rays taken
of their bones, in order to determine whether the tumor has spread to them.