Alcohol as a risk factor for cancer - Does alcohol cause cancer?

Alcohol consumption is the most important risk factor for development of oral cancer in non-smokers. It is also considered as the second independent major risk factor for the development of oral cancer. It is estimated that an average consumption of over 30 ml of alcohol per day increases the risk of oral cancer linearly with the quantity of alcohol consumed. Though any form of alcohol when consumed in large

quantities is dangerous, it is believed that dark colored drinks are more hazardous (as they may contain higher beverage congeners such as nitrosamines, hydrocarbons and other impurities which are known carcinogens). Carcinogens present in the tar are insoluble in saliva but are highly soluble in alcohol and easily absorbed in the oropharynx.

The International Agency for Research on Cancer published a monograph in 1982, which details the various methods in which alcohol predisposes to head and neck cancers.

❍ Ethyl alcohol increases the permeability of oral mucosa. It also dehydrates the mucosa. It has a solvent action on the keratinocyte membrane thereby allowing the passage of carcinogens into proliferating cells where they may exert a mutagenic action.

❍ The immediate metabolite of ethanol is acetaldehyde, which readily damages cells. It is believed that those who are rapid acetylators are at increased risk of developing cancers.

❍ Alcoholic liver disease is common in heavy drinkers and this minimizes the detoxification of carcinogens.

❍ Alcohol, owing to its high calorific value, suppresses appetite in heavy drinkers. This predisposes to nutritional deficiency which in turn is a risk factor for cancers. Compared to non-users, alcohol users are 3.6 times more likely to have oropharyngeal cancer, 5.8 times for tobacco users, and 19 times for users of both alcohol and tobacco.

Reference: Textbook of Oral Medicine, Oral Diagnosis and Oral Radiology Second Edition, Ravikiran Ongole, Page no: 384

Kaposi’s sarcoma is a tumor of:

 # Kaposi’s sarcoma is a tumor of:

A. Smooth muscle

B. Striated muscle

C. Blood vessels

D. Reticuloendothelial system

The correct answer is C. Blood vessels.

Kaposi’s sarcoma is a low-grade and relatively indolent malignant multifocal tumour of lymphatics or blood vessels caused by infection with human herpesvirus 8 (HHV-8). Its status as a true malignant neoplasm is unclear as it shows a range of behaviours. Most patients are immunosuppressed. Therapeutic immunosuppression with ciclosporin and tacrolimus can be associated with Kaposi’s sarcoma, but by far the main predisposing condition is HIV infection, and almost all oral Kaposi’s sarcoma is in HIV-infected patients. Among HIVinfected patients, Kaposi’s sarcoma affects mainly men who have sex with men. Antiretroviral therapy for HIV has greatly reduced the incidence of Kaposi’s sarcoma, but it remains the most common type of intraoral sarcoma.

Ref: Cawson’s Essentials of Oral Pathology and Oral Medicine, 9th Edition Page no 380

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Chemotherapeutic agent has following side effects EXCEPT:

 # Chemotherapeutic agent has following side effects EXCEPT:

A. Hair loss

B. Diarrhoea

C. Hypertension

D. Mucositis

The correct answer is C. Hypertension.

Majority of the cytotoxic drugs have more profound effect on rapidly multiplying cells, because the most important target of action are the nucleic acids and their precursors, and rapid nucleic acid synthesis occurs during cell division. Many cancers (especially large solid tumours) have a lower growth fraction (lower percentage of cells are in division) than normal bone marrow, epithelial linings, reticuloendothelial (RE) system and gonads. These tissues are particularly affected in a dose-dependent manner by majority of drugs; though, there are differences in susceptibility to individual members.

KD Tripathi Page 859, 7th Edition

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Most common oral change of nutritional anemia is:

# Most common oral change of nutritional anemia is:

A. Atrophic glossitis

B. Leukoplakia

C. Lichen planus

D. Hypertrophic glossitis

The correct answer is A. Atrophic glossitis.

Glossitis is one of the more common symptoms of pernicious anemia. The patients complain of

painful and burning lingual sensations which may be so annoying that the dentist is often consulted first for local relief. The tongue is generally inflamed, often described as ‘beefy red’ in color, either in entirety or in patches scattered over the dorsum and lateral borders. In some cases, small and shallow ulcers — resembling aphthous ulcers — occur on the tongue. Characteristically, with the glossitis, glossodynia and glossopyrosis, there is gradual atrophy of the papillae of the tongue that eventuate in a smooth or ‘bald’ tongue which is often referred to as Hunter’s glossitis or Moeller’s glossitis and is similar to the ‘bald tongue of Sandwith’ seen in pellagra. Loss or distortion of taste is sometimes reported accompanying these changes. The fiery red appearance of the tongue may undergo periods of remission, but recurrent attacks are common.

Shafer 7th Edition, Page no: 763

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Cyanosis of lips is a common finding in all EXCEPT:

# Cyanosis of lips is a common finding in all EXCEPT:

A. Polycythemia

B. Sickle cell anemia

C. Iron deficiency anemia

D. Congenital heart disease

The correct answer is: C. Iron deficiency Anemia.

In general， cyanosis becomes apparent when,  the concentration of reduced hemoglobin in capillary blood exceeds 40 g/L (4 g/dL). It is the absolute，rather than the relative，quantity of reduced hemoglobin that is important in producing cyanosis. Thus, in a patient with severe anemia，the relative quantity of reduced hemoglobin in the venous blood may be very large when considered in relation to the total quantity of hemoglobin in the blood. However, since the concentration of the latter is markedly reduced, the absolute quantity of reduced hemoglobin may still be low, and， therefore， patients with severe anemia and even marked arterial desaturation may not display cyanosis. Conversely， the higher the total hemoglobin content， the greater the tendency toward cyanosis; thus， patients with marked polycythemia tend to be cyanotic at higher levels of Sao， than patients with normal hematocrit values.

CAUSES OF CYANOSIS

Central Cyanosis

1. Decreased arterial oxygen saturation

     A. Decreased atmospheric pressure- high altitude

     B. Impaired pulmonary function

          - Alveolar hypoventilation

          - Inhomogeneity in pulmonary ventilation and perfusion (perfusion of hypoventilated alveoli)

          - Impaired oxygen diffusion

     C. Anatomic shunts

         - Certain types of congenital heart disease

         - Pulmonary arteriovenous fistulas

         - Multiple small intrapulmonary shunts

    D. Hemoglobin with low affinity for oxygen

2. Hemoglobin abnormalities

    A. Methemoglobinemia-hereditary，acquired

    B. Sulfhemoglobinemia-acquired

    C. Carboxyhemoglobinemia (not true cyanosis)

Peripheral Cyanosis

A. Reduced cardiac output

B. Cold exposure

C. Redistribution of blood flow from extremities

D. Arterial obstruction

E. Venous obstruction

Ref: Harrison's 19th edition, Page 249

Dietary approaches to stop hypertension (DASH) approximately reduces systolic blood pressure by:

# Dietary approaches to stop hypertension (DASH) approximately reduces systolic blood pressure by:

a. 2-4mm Hg

b. 4-9mm Hg

c. 2-8mm Hg

d. 8-14mm Hg

The correct answer is D. 8-14 mm Hg.

Limitation of alcohol consumption will lower by 2-4mm Hg, physical activity will

reduce by 4-9mm Hg and dietary sodium reduction will lower by 2-8mm Hg. Adoption of DASH eating plan will reduce SBP by 8-14 mm Hg.

Ref: Burkett 12th ed, page number: 366

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 # Cytomegalovirus that causes severe oral ulcers is also known as:

a. HHV 5

b. HHV4

c. HHV 2

d. HHV1

The correct answer is B. HHV4

HHV 4 is also known as cytomegalovirus, HHV 5 is Epstein barr, HHV 2 is herpes

simplex virus 2 and HHV 1 is herpes simplex virus 1. 

Ref: Burkett 12th ed, page number: 59

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