Article Info
Dr. NORA AL-NAHEDH
Year: 2000
Month: January
Issue: 1
Reference: Alkhan A., Alhamdan N., AlEid H.,Dr. NORA AL-NAHEDH .Saudi Epidemiology Bulletin. 2000;7(1):.
Non-Hodgkin's Lymphomas (NHL) are tumors of the lymphoreticular system. They represent the seventh tumor group in frequency worldwide, with age-adjusted incidence rates of 7.7/100,000 among men and 5.2/100,000 among women [1].
In Saudi Arabia there were 1,197 cases of NHL diagnosed between January 1994 and December 1996 among Saudis, accounting for 7.4% of all newly diagnosed cancers. NHL ranked second for the male and fourth for the female populations [2]. In the Eastern Region there were 68 cases of NHL diagnosed in the interval between January 1997 and December 1998 [3].
The aim of this study was to determine the risk factors for NHL in the Eastern Region of Saudi Arabia. A hospital-based case-control study was conducted. NHL cases for the years 1997 and 1998 were identified by reviewing the data in the National Cancer Registry and from the participating hospitals. Controls were selected among subjects who had no history of cancer. admitted as in-patients or outpatients in the same hospitals. Face-to-face interviews were conducted. Interview topics covered demographic characteristics (age. sex, and nationality), family and medical history, use of therapeutic drugs, history of viral infection, rheumatoid arthritis, blood transfusion. exposure to radiation. smoking, use of hair-colour products and occupation. Odds Ratios (OR). 95% confidence intervals (95% CI) were calculated. A P-value <0.05 was considered statistically significant.
A total of 205 subjects (41 cases and 164 controls) were included in the analysis. Out 41 cases, 27 (65.9%) were males and 33 (80.5%) were Saudis. A statistical significance of elevated risk for NI-IL was associated with female gender (OR=3.73. 95%CI=1.55-9. P-value=0.002). black skin (OR=4.81. 95% CI=1.33-13.1. P-value=0.008). and agricultural workers (OR=5.56. 95%0=1.2-26.6. P-value=0.017) (Table.1) .
Editorial note:
This is the first study to determine the risk factors for NHL in the Eastern region of Saudi Arabia. Most of our results were consistent with previous studies. A previous investigation reported a lower incidence rate of NHL for blacks than whites [4], but our results did not support this. The statistically significant elevated risk for NHL among blacks in our study may be explained by the fact that most of the residents of the Eastern region are of a brown race, and only a small proportion are of black race.
The elevated risk for NHL with living in a rural area in our results is probably due to the fact that the Eastern region is mainly an urban area with only a small number of people (Bedouins) living in rural areas.
The association between NHL and the use of drugs to treat ulcers is supportive of a previous study that suggested a link between cancer and use of cimetidine and other histamine H2-receptor antagonists used in the treatment of ulcers [5].
Experimental studies have shown that hair-colouring products contain mutagenic and carcinogenic components, which vary by hair-colour product type and colour [6]. In the present study, the variation of NHL risk by product type is somewhat consistent with what would be expected based on concentration and formulation of the various hair-colour products. In this study we found that dye and de-coloration types of hair-colour products, which may contain carcinogenic and amino compound, have an increased risk for NHL whereas henna, which is a natural product for hair-coloring, had no associated risk for NHL.
The small numbers of exposure to some variables in this study are most probably attributed to the small number of our studied cases. An additional study on a larger number of cases within more recent years would be very supportive.
References
- Parkin DM, Muir CS, Whelan SL, Gao YT, Ferly J and Powell L. Parkin DM, Muir CS, Whelan SL et al. editors. Cancer incidence in five continents. Volume VI. IARC Scientific Publication No. 120. Lyon: International Agency for Research on Cancer; 1992.
- Ministry of Health. National Cancer Registry: Cancer Incidence Report (1994-1996). 1999; 26-27.
- Ministry of Health. National Cancer Registry: (Through verbal communication).
- Scherr PA, Mueller NE. Non-Hodgkin's lymphoma. In: Cancer Epidemiology and Prevention. Schottenfeld D, Joseph F, Fraumeni TR. 2nd Edition. Michigan. University of Michigan School of Public Health, 1996.
- Watson SA, Wilkinson LJ, Roberston JFR, et al. 1993. Effect of histamine on the growth of human gastrointestinal tumors: reversal by cimetidine. Gut 34:1091-6.
- Zahm SH, Welsenburger DD, Babbit PA, et al. 1992. Use of hair coloring products and the risk of lymphoma, multiple myeloma, and chronic lymphocytic leukemia. Am J public Health 82:990-997.
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Table 1. Risk factors for Non-Hodgkin's Lymphoma among cases and controls, Eastern Region, 1997-1998
|
|||||||
|
Characteristic
|
Cases
(41)
|
Controls
(164)
|
OR
|
95%CI
|
P-value
|
||
|
No.
|
%
|
No.
|
%
|
||||
|
Age group
|
|||||||
|
20 & under
|
8
|
19.5
|
35
|
21.3
|
0,89
|
0.34-2.3
|
0.49
|
|
21-40
|
10
|
24.4
|
68
|
41.5
|
0.46
|
0.19-1.1
|
0.03
|
|
41-60
|
10
|
34.1
|
40
|
24.4
|
1.61
|
0.72-3.6
|
0.14
|
|
60 & above
|
9
|
22
|
21
|
12.8
|
1.92
|
0.73-4.9
|
0.14
|
|
Gender
|
|||||||
|
Females
|
14
|
34,1
|
20
|
12.2
|
3.73
|
1.55-9
|
0.002
|
|
Skin color
|
|||||||
|
White
|
3
|
7.3
|
14
|
8.5
|
0.85
|
0.18-3.4
|
0.54
|
|
Black
|
8
|
19,5
|
9
|
5.5
|
4.81
|
1.33-13.1
|
0:008
|
|
Brown
|
30
|
72,2
|
141
|
86
|
0.44
|
0.18-1.1
|
0.05
|
|
Residence
|
|||||||
|
Rural
|
2
|
4.9
|
7
|
4.3
|
1.15
|
0.00-6.5
|
0.57
|
|
Urban
|
39
|
95.1
|
157
|
95.7
|
0.87
|
0.15-6.4
|
0.57
|
|
Education level
|
|||||||
|
Illiterate
|
12
|
29.3
|
51
|
31.1
|
0.92
|
0.40-2.1
|
0.49
|
|
less than secondary
|
15
|
36.6
|
76
|
46.3
|
0.67
|
0.37-1.8
|
0.37
|
|
Secondary & above
|
14
|
34.1
|
37
|
22.5
|
1.8
|
0.89-4.8
|
0.071
|
|
Medical conditions
|
|||||||
|
Herpes simplex virus
|
6
|
14.6
|
10
|
6.1
|
2.64
|
0.78-8.7
|
0.073
|
|
Hepatitis C virus
|
1
|
2.4
|
1
|
0.6
|
4.08
|
0.00-155.6
|
0.36
|
|
Rheumatoid arthritis
|
3
|
7.3
|
4
|
2.4
|
3.16
|
0.53-17.9
|
0.15
|
|
Blood transfusion
|
2
|
4.9
|
2
|
1.2
|
4.15
|
0.40-43.6
|
0.18
|
|
Therapeutic
|
|||||||
|
Cimetidine & other H2-receptor antagonists
|
2
|
4.9
|
2
|
1.2
|
4.15
|
0.40-43.6
|
0.18
|
|
Diagnostic X-ray
|
38
|
92.7
|
140
|
85.4
|
2.17
|
0.57-9.7
|
0.16
|
|
Smoking
|
9
|
22
|
41
|
25
|
0.84
|
0.34-2.1
|
0.43
|
|
Hair-color products
|
|||||||
|
Dye
|
4
|
10·
|
7
|
4.3
|
2.49
|
0.57-10.3
|
0.15
|
|
Henna
|
3
|
7.3
|
12
|
7.3
|
1
|
0.21-4.1
|
0.61
|
|
Decoloration
|
1
|
2.4
|
2
|
1.2
|
2.02
|
0.00-30
|
0.49
|
|
Occupation
|
|||||||
|
Agricultural worker
|
5
|
12.2
|
4
|
2.4
|
q.56
|
1.20-26.6
|
0.017
|
|
Chemical industry
|
1
|
2.4
|
8
|
4.9
|
0.49
|
0.02-4.1
|
0.43
|
|
Textile worker
|
1
|
2.4
|
5
|
3
|
0.8
|
0.00-7.4
|
0.66
|