4-5-13Effects of Neoplasia on the Host

8/13/2019 4-5-13Effects of Neoplasia on the Host

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Effects of Neoplasia on the Host


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Direct Effects of Primary Tumors Local Growth

The signs and symptoms vary with

The site of the lesion , The nature of the surrounding anatomic structures The overall rate of growth


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The growing tumor May compress or destroy adjacent structures,

Cause inflammation, pain, vascular changes , Functional deficits ( varying degrees)


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Tumor growing near a vital structure (eg, the brainstem),

Such local effects may be lethal Regardless of whether the neoplasm is benign or

malignant.


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Neoplasms growing in a confined area , (cranialcavity), form space-occupying lesions

Local compressive effects General potentially lethal increase in intracranial

pressure .


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Local and Hormonal Effects

Critical location is the pituitary adenoma . Benign and possibly not producing hormones,

expansile growth can destroy the remaining pituitary leading to serious Endocrinopathy.

Cancers arising within or metastatic to an endocrine

gland may cause an endocrine insufficiency bydestroying the gland.


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Neoplasms in the gut, may cause obstructionas they enlarge.

Infrequently, peristaltic movement telescopesthe neoplasm and its affected segment into thedownstream segment, producing anobstructing intussusception


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Endocrine neoplasms manifestations by elaborationof hormones.

Benign tumors Cancers, which may be sufficiently undifferentiated

to have lost such capability. A benign -cell adenoma of the pancreatic islets less

than 1 cm in diameter may produce sufficient insulinto cause fatal hypoglycemia.


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Nonendocrine tumors may elaborate hormonesor hormone-like products and give rise toParaneoplastic syndromes


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Cancer Cachexia ( wasting syndrome )

Progressive loss of body fat and lean body mass Accompanied by profound weakness, anorexia, and

anemia. The origins are obscure. The action of soluble factors Cytokines produced by the tumor & By the host in response to the tumor.


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Anorexia a common problem in patients with cancer

Abnormalities in taste and central control of appetite Calorie expenditure often remains high, & BMR hi

despite reduced food intake. Starvation, (daptational lowering of metabolic rate) Cancer cachexia, there is equal loss of fat and muscle, Whereas in starvation the muscle mass is relatively

preserved at the expense of fat stores


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TNF produced by macrophages or possibly sometumor cells is a mediator of the wasting syndromethat accompanies cancer .

IL-1, IFN- , and leukemia inhibitory factor synergizewith TNF


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Local Effect ResultMass Presentation as tissue lump or tumor

Ulcer (nonhealing) Destruction of epithelial surfaces (eg,stomach, colon, mouth, bronchus)

Hemorrhage From ulcerated area or eroded vesselPain Any site with sensory nerve endings

Seizures Tumor mass in brain;Cerebral dysfunction Wide variety of deficits depending on siteObstruction Of hollow viscera by tumor in the wall;

bronchial obstruction leads to pneumonia;

obstruction of bile ducts causes jaundice


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Perforation Of ulcer in viscera; in bowel mayproduce peritonitis

Bone destruction Pathologic fracture, collapse of boneInflammation Of serosal surface, pleural effusion,

pericardial effusion, ascitesSpace occupyinglesion

Raised intracranial pressure in brainneoplasms;anemia due to displacement ofhematopoietic cells by metastases to the

bone marrow

Localized loss ofsensory or motorfunction

Compression or destruction of nerve ornerve trunk; classic example is involvementof recurrent laryngeal nerve by lung orthyroid cancer , with resulting hoarseness

Edema Due to venous or lymphatic obstruction


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Clinical Effect Causative FactorsVarious hormonal effects,eg, hypoglycemia,Cushing's syndrome,gynecomastia,hypertension

Hormone produced by endocrinetumors;so called ectopic hormones

produced by nonendocrineneoplasms

Anemia Chronic blood loss orunknown toxic effects cause IDAReplacement of marrow by tumor

causes leukoerythroblastic type


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Disseminated intravascularcoagulation

Widespread cancer (probably due torelease of thromboplastic substances

by dying tumor cellsPolycythemia Renal cancer, hepatoma, uterine

myoma, in some instances due toerythropoietin like substance produced

by tumor.

Gout Hyperuricemia due to excess nucleicacid turnover; may be precipitated bycytotoxic therapy.

Myasthenia gravis, myasthenic (Eaton Lambert) syndrome

Thymoma especially; autoantibodies

Clubbing of fingers Lung cancer and other intrathoracicneoplasms especially; mechanismunknown


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Direct Effects of Growth of Metastases

Metastatic deposits form growing tumors that may compressand destroy adjacent tissues in the same way that a primarylesion does.

The effects associated with a primary lesion are the directresult of the actions of the tumor on a single site in the body;in metastatic disease, more than one metastasis may be presentand a multiplicity of effects may occur.


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4-5-13Effects of Neoplasia on the Host