W5: L6- Effects of tumours

Question 1

What are the two categories of tumour effects?

Answer 1

• Local effects
• Distant effects

Question 2

Tumours present clinical effects to patients. What are the clinical effects of tumours attributable to?

Answer 2

They are attributable to:
- tumour location,
- cell of origin and
- tumour behaviour

Question 3

Local effects may occur following benign and malignant neoplasms due to________

Answer 3

• Compression
• Invasion
• Ulceration with destruction of adjacent cells

Question 4

What is the local effect of ‘compression’ by neoplasia on nearby structures?

Answer 4

example: pituitary adenoma:

Compression by neoplasia may obliterate the adjacent functioning pituitary, resulting in hypopituitarism (hamper hormone secretions by pituitary gland) because of the confined space in which the gland is found.

Question 5

What is the local effect of ‘invasion’ by neoplasia on nearby structures?

Answer 5

Invasion leads to erosion and
destruction of local structures

example: erosion of a pulmonary artery by a carcinoma of the lung

Question 6

What is the local effect of ‘ulceration’ caused by neoplasia or tumour on nearby structures?

Answer 6

Ulceration leads to secondary infections and bleeding.

example: basal cell carcinoma of the skin (‘rodent ulcer’)

*these ulcers can result from erosive destructive growth of neoplasia (malignant); or might be secondary to pressure (benign or malignant)

Question 7

What are the characteristic of neoplasms of the gut and urinary tract?

Answer 7

• melaena (blood in the stool)
• haematuria

*These 2 cause anemia

Question 8

Which tumours, between benign and malignant have hormonal effects?

Answer 8

Benign.

They arise in endocrine glands and, since they are similar to the normal cells of the endocrine glands producing hormones, they take over the function and produce the hormones as well.
(which is something malignant cells cannot do since they are undefferentiated and very different from normal hormone secrting cells)

Question 9

Name tumours occuring in the cells of the hormone-secreting organs or glands, and state the impacts of those tumours in hormone production.

Answer 9

• A “benign β-cell adenoma” of the pancreatic islets, less than 1 cm in diameter may produce enough insulin to cause fatal hypoglycemia.
• Thyroid Adenoma cause thyrotoxicosis (state of excess thyroid hormone in the bloodstream)
• Adrenocortical adenoma cause Cushing’s syndrome
• A parathyroid adenoma cause hyperparathyroidism

Question 10

What is a non-specific tumour effect that can be seen on cancer patients?

Answer 10

Cachexia

Question 11

What is cachexia?

Answer 11

A non-specific metabolic effect accompanied by wasting syndrome, progressive loss of body fat and lean body mass,
accompanied by profound weakness, anorexia, and anaemia

Question 12

Cachexia is not caused by nutritional demands of a tumour. What causes cachexia?

Answer 12

Results from the action of soluble factors such as cytokines produced by the tumor, and by
the host in response to the tumor

*Weight loss can also be due to interference with nutrition eg. oesophageal obstruction,
severe pain or depressive illness

Question 13

What are paraneoplastic syndromes?

*They’re seen only with malignant tumours never benign

Answer 13

Paraneoplastic syndromes are a group of rare disorders that occur when cancerous tumors produce substances that affect distant tissues or organs, often leading to symptoms unrelated to the primary tumor’s location or its spread. These syndromes are caused by an immune system response to the presence of cancer, rather than by direct invasion or metastasis of the tumor

Question 14

Name just six paraneoplastic syndromes.

Answer 14

• Endocrinopathy: Characterised by ectopic (abnormal) hormone priduction.
• Hypercalcemia: most common paraneoplastic syndrome. It is commonly found in squamous cell carcinomas of the lung due to production of parathyroid hormone related protein.
• Neuromyopathic paraneoplastic syndromes:
  Clinically presents with;
  -Peripheral neuropathy
  -Cortical cerebellar degeneration
  -Polymyopathy resembling polymyositis
  -Myasthenic syndrome ~ myasthenia gravis
• ACANTHOSIS NIGRICANS:
  -skin condition with thickened hyperpigmented skin
  -May arise in adults most commonly seen with gastrointestinal
  adenocarcinomas
• HYPERTROPHIC OSTEOATHROPATHY:
  -seen in patients with lung carcinoma
  -Clinically presents with: Periosteal new bone formation, arthritis of adj jts, clubbing of digits
• VASCULAR EFFECTS:
  -Presents with Migratory thrombophlebitis: (Trousseau syndrome)»A pathological phenomenon of clots forming, resolving and re-appearing elsewhere in the body.
  -Seen with the carcinomas of the pancreas or lung
  -Acute disseminated intravascular coagulation (prostatic adenocarcinoma, leukemia)