Effects of tumors lecture 18

Question 1

True or false: Not all tumors can cause Morbidity and mortality

Answer 1

False, all tumors can cause morbidity or mortality even benign tumors

Question 2

Clinical effects of tumors are attributed to

Answer 2

their location, cell of origin, and their behaviour

and their effects can be the local or distant site

Question 3

What are the local effects of tumors?

Answer 3

• May occur secondary to benign or malignant neoplasm due to compression, invasion, and ulceration with the destruction of adjacent structures
• Effects are attributable to the location and behavior of the tumor

Question 4

Give an example of a local effect: Compression

Answer 4

1. Pituitary adenoma
   * Functionally active or inactive (may produce hormones or not)
   * As it enlarges, it compresses the adjacent functioning pituitary.
   * This may result in hypopituitarism (pituitary gland can no longer produce hormones )
2. Brain tumor
   * low grade / high grade
   * As it enlarges, it compresses the normal brain structure such as vesicles
   * This may result in a shift of the midline and raise intracranial pressure due to confined space within the cranium

Question 5

Give an example of local effects: Invasion

Answer 5

> Malignant neoplasm have more serious local effects as they invade leading to erosion and destruction of local structures
May be fetal in the case of a vital structure
eg Erosion of pulmonary artery by a carcinoma of the lung or perforation of the colon by an adenocarcinoma or large cell undifferentiated carcinoma of the lung invading into the mediastinum and surrounding great vessels

Question 6

Give an example of local effects : Ulceration

Answer 6

> Tumors may cause ulceration of skin or mucosa either by their erosive destructive growth (malignant ) or secondary to pressure (benign/malignant)
*Ulceration leads to secondary infection and bleeding

> Colon adenocarcinoma
*An important cause of anemia is melaena ( blood in the stool) and haematuria which is characteristic of the neoplasm of the gastrointestinal and urinary tracts

Question 7

What are the metabolic effects (tumor -specific effects )

Answer 7

> Tumors arising in endocrine glands retain the functional properties of the parent tissues and produce the hormone

> More common with benign than malignant because they are poorly differentiated and thus lose their function

> Clinical effects are common ,these tumors are autonomous and their total number of functioning cells are greater than the normal tisssue

Question 8

Give an example of the metabolic effects: Tumour Specific effects

adenoma of the pancreas and adrenocortical adenoma

Answer 8

1. Adenoma of the pancreas
   * A benign beta-cell adenoma may be functional or not. If functional, it may produce enough insulin to cause fetal hypoglycemia
2. Adrenocortical adenoma
   >Cushing syndrome

Question 9

Give an example of the metabolic effects: Tumour Specific effects

Cachexia

Answer 9

*Wasting syndrome in patients
*Progressive loss of body fat and lean body mass accompanied by profound weakness, anorexia, and anemia
*Result from the action of soluble factors such as cytokines produced by the tumor and by the host cell in response to the tumor .
May occur quite early in the course of the disease,especially in patients with carcinoma of the lung

Question 10

T/F : Not all weightloss in cancer is due to cachexia

Answer 10

True ,some may be due ro esophageal obstruction ,severe pain and depressive illness

Question 11

What is paraneoplastic syndrome

Answer 11

The constellation of symptoms in patients with cancer that cannot be explained either by local or distant spread of the tumor or by the production of hormones that usually produced by the tissue from which the tumor arose

Question 12

Why are paraneoplastic syndromes important to recognize

Answer 12

• May represent earliest manifestation of an occult neoplasm
• May represent significant clinical problems and may even be lethal
• May mimic metastatic disease and therefore confound treatment

Question 13

Paraneoplastic syndrome : HYPERCALCAEMIA

Answer 13

> Probably the most common paraneoplastic syndrome
Two general processes are involved in cancer -associated hypercalcemia
1.Osteolysis induced by cancer ,may be a primary cancer in the bone or metastatic to bone from another site ,therefore it is not paraneoplastic hypercalcemia due to skeletal metastases is not paraneoplastic )

2. the production of calcemic humoral substances by extra-osseous neoplasm (it is paraneoplastic )

commonly found in squamous cell carcinoma of the lung due to production of parathyroid hormone related protein (paraneoplastic because the lung doe not normally produce PTH nor it is located by the bone)

Question 14

Paraneoplastic syndrome : Endocrinopathy

Answer 14

• Due to ectopic hormone production
• Hormone production by non-endocrine organs
• Cushing’s syndrome is the most common endocrinopathy ,up to 50% of these patients have carcinoma of the lung
• It is due to excess production of corticotropin (ACTH) or corticotropin-like peptides

This is considered a paraneoplastic syndrome because a lung does not produce ACTH

Question 15

Paraneoplastic syndrome : Acanthosis nigricans

Answer 15

• Skin condition with thickened hyperpigmented skin
• Usually in flexures
• Arises as a benign condition in childhood = not tumor related
• May arise in adults with underlying cancer ,mostly commonly GIT adenocarcinomas

Question 16

Paraneoplastic syndrome :Hypertrophic osteoarthropathy

Answer 16

> Periosteal new bone formation ,arthritis of joints ,clubbing of digits
cause unknown
Associated with many condition involving various organ systems
As a paraneoplastic syndrome : 1-10 of pt with lung carcinomas
Clubbing id not a paraneoplastic syndrome because it can be caused by other diseases

Question 17

Paraneoplastic syndrome: Vascular effects

Answer 17

> Migratory thrombophlebitis (Trousseau syndrome /sign )
*Pathological phenomenon of vessel of vessel inflammation (phlebitis ) associated with blood clot (thrombi) which are recurrent or appearing in different locations over time

• Occurs when a deep seated cancer eg carcinoma of the pancreas or lung
• Due to tumor-associated inflammation and platelets aggregation factors and procoagulant produced by tumor cells causes arterial and venous thrombi
• Non-bacterial thrombotic endocarditis in patients with mucin-secreting carcinomas especially of the GIT ,lung or ovary

Question 18

Neuromyopathic paraneoplastic syndrome

Answer 18

• Peripheral neuropathy
• Cortical cerebellar degeneration
• Polymyopathy resembling polymyositis
• Myasthenic syndrome resembling myasthenia gravis

Question 19

Summary

Answer 19

Effects of tumours may be:
Local e.g. compression, invasion and ulceration (both benign and malignant)
Metabolic
Tumour-specific effects – effects of hormones produced by the tumour cells (benign and malignant)
Non-specific metabolic effects e.g. cachexia (malignant)
Paraneoplastic – symptom complexes in patients with cancer (malignant)