Age distribution, polyps and rectal cancer in the Egyptian population-based cancer registry

Table 1 Characteristics of study population and cancer patterns in Gharbiah, Egypt (1999-2007)

Variable	n (%)
Total cases	1364 (100.0)
Gender
Male	737 (54.0)
Female	627 (46.0)
Residence
Urban	752 (55.1)
Rural	612 (44.9)
Year of diagnosis
1999	135 (9.9)
2000	149 (10.9)
2001	144 (10.6)
2002	154 (11.3)
2003	151 (11.1)
2004	137 (10.0)
2005	161 (11.8)
2006	171 (12.5)
2007	162 (11.9)
District of residence
Tanta	437 (32.0)
El Mehalla	355 (26.0)
Kafr El Zayat	118 (8.7)
Zefta	98 (7.2)
Samanoud	82 (6.0)
El Santa	103 (7.6)
Kotour	78 (5.7)
Basyoon	93 (6.8)

Table 2 Age and clinical characteristics of study population in Gharbiah, Egypt (1999-2007)

Variable	n (%)
Age(yr)
<40	300 (22.0)
≥40	1064 (78.0)
Basis of diagnosis
Histology of primary	1210 (88.7)
Histology of metastases	58 (4.3)
Death certificate only	52 (3.8)
Others1	44 (3.2)
Tumor site
Colon	856 (62.8)
Right	347 (40.5)
Left	331 (38.7)
NOS	178 (20.8)
Rectum	508 (37.2)
Grade
I	96 (7.0)
II	702 (51.5)
III	155 (11.4)
IV	61 (4.5)
Unknown	350 (25.7)
Polyps
Present	38 (2.8)
< 40 yr	9 (23.7)
≥ 40 yr	29 (76.3)
Male	19 (50.0)
Female	19 (50.0)
Not present	1326 (97.2)
Mucinous carcinoma
Present	318 (23.3)
< 40 yr	102 (32.1)
≥ 40 yr	216 (67.9)
Not present	1046 (76.7)
Histopathology
Adenocarcinoma	1186 (87.0)
Carcinomas2	50 (3.7)
Other specified types of cancers	16 (1.2)
Unspecified types of cancers	112 (8.2)

Table 3 Incidence rates (per 10⁵) and incidence rate ratios (95% confidence interval) by gender and urban-rural status for colorectal cancer patients in Gharbiah (1999-2007)

Age (yr)	Urban incidence		Rural incidence		Urban-rural IRR (95% CI)
	Male	Female	Male	Female	Male	Female
Total
5-9	0.17	0.00	0.00	0.00	-	-
10-14	0.00	0.35	0.00	0.16	-	2.23 (0.31, 15.82)
15-19	1.00	0.17	0.78	0.52	1.27 (0.47, 3.45)	0.32 (0.04, 2.59)
20-24	2.70	2.29	0.77	0.77	3.50 (1.57, 7.80)	2.97 (1.25, 7.05)
25-29	3.44	2.27	1.29	1.22	2.67 (1.30, 5.47)	1.86 (0.80, 4.30)
30-34	4.47	4.39	3.40	1.16	1.31 (0.74, 2.34)	3.79 (1.74, 8.28)
35-39	6.56	4.55	3.54	3.81	1.85 (1.07, 3.20)	1.19 (0.64, 2.24)
40-44	12.03	17.22	5.60	3.86	2.15 (1.35, 3.42)	4.46 (2.70, 7.35)
45-49	23.67	16.61	7.11	4.47	3.33 (2.22, 4.99)	3.72 (2.24, 6.16)
50-54	33.30	30.36	11.92	10.10	2.79 (1.93, 4.05)	3.00 (2.05, 4.40)
55-59	32.06	24.93	7.65	9.28	4.19 (2.66, 6.60)	2.69 (1.76, 4.11)
60-64	41.86	29.89	13.24	11.55	3.16 (2.03, 4.92)	2.59 (1.60, 4.18)
65-69	49.14	24.40	12.27	9.04	4.01 (2.34, 6.86)	2.70 (1.47, 4.95)
70-74	45.38	39.93	16.36	7.79	2.77 (1.43, 5.39)	5.13 (2.44, 10.77)
75+	40.95	36.28	16.36	11.99	2.50 (1.21, 5.19)	3.03 (1.52, 6.03)
Colon
5-9	0.17	0.00	0.00	0.00	-	-
10-14	0.00	0.17	0.00	0.16	-	1.11 (0.10, 12.29)
15-19	0.33	0.17	0.50	0.52	0.67 (0.14, 3.21)	0.32 (0.04, 2.59)
20-24	1.80	2.10	0.39	0.43	4.67 (1.60, 13.67)	4.90 (1.70, 14.11)
25-29	1.72	1.59	0.55	0.51	3.12 (1.08, 8.98)	3.12 (0.99, 9.83)
30-34	2.98	2.32	1.70	0.58	1.75 (0.83, 3.70)	4.01 (1.34, 11.97)
35-39	4.56	2.42	2.32	2.45	1.97 (1.01, 3.83)	0.99 (0.43, 2.28)
40-44	7.78	8.61	3.63	2.18	2.14 (1.20, 3.82)	3.94 (2.00, 7.79)
45-49	14.95	10.79	5.69	2.61	2.63 (1.63, 4.23)	4.14 (2.16, 7.93)
50-54	22.38	15.67	7.48	6.59	2.99 (1.89, 4.75)	2.38 (1.44, 3.91)
55-59	22.81	16.97	5.54	5.95	4.12 (2.41, 7.03)	2.85 (1.69, 4.81)
60-64	28.21	21.59	6.62	5.96	4.26 (2.36, 7.70)	3.62 (1.94, 6.75)
65-69	27.30	14.85	6.43	5.24	4.25 (2.04, 8.86)	2.84 (1.29, 6.25)
70-74	26.27	26.04	12.27	4.67	2.14 (0.95, 4.85)	5.57 (2.16, 14.36)
75+	30.03	32.46	10.52	6.85	2.86 (1.18, 6.89)	4.74 (2.04, 10.98)
Rectum
5-9	0.00	0.00	0.00	0.00	-	-
10-14	0.00	0.17	0.00	0.00	-	-
15-19	0.66	0.00	0.28	0.00	2.34 (0.58, 9.34)	-
20-24	0.90	0.19	0.39	0.34	2.34 (0.68, 8.07)	0.56 (0.06, 4.99)
25-29	1.72	0.68	0.74	0.71	2.34 (0.88, 6.22)	0.96 (0.25, 3.69)
30-34	1.49	2.06	1.70	0.58	0.88 (0.34, 2.24)	3.57 (1.17, 10.90)
35-39	2.00	2.12	1.22	1.36	1.64 (0.62, 4.30)	1.56 (0.59, 4.10)
40-44	4.25	8.61	1.97	1.68	2.16 (0.98, 4.73)	5.13 (2.44, 10.77)
45-49	8.72	5.81	1.42	1.86	6.13 (2.72, 13.85)	3.12 (1.39, 7.03)
50-54	10.92	14.69	4.44	3.51	2.46 (1.31, 4.61)	4.18 (2.28, 7.67)
55-59	9.25	7.96	2.11	3.33	4.38 (1.86, 10.33)	2.39 (1.15, 4.95)
60-64	13.65	8.30	6.62	5.59	2.06 (1.03, 4.13)	1.49 (0.67, 3.31)
65-69	21.84	9.55	5.84	3.81	3.74 (1.70, 8.24)	2.51 (0.97, 6.50)
70-74	19.11	13.89	4.09	3.12	4.67 (1.41, 15.52)	4.46 (1.34, 14.80)
75+	10.92	3.82	5.84	5.14	1.87 (0.50, 6.96)	0.74 (0.15, 3.68)

IRRs: Incidence rate ratios; 95% CI: 95% confidence itervals.

Table 4 Comparison of incidence rates for colorectal cancer patients in the 8 districts of Gharbiah (1999-2007)

	Young (< 40 yr)		Old (≥ 40 yr)		Colon		Rectum
District	IR	IRR (95% CI)	IR	IRR (95% CI)	IR	IRR (95% CI)	IR	IRR (95% CI)
Tanta	1.52	1.93 (1.23, 3.04)	18.53	2.08 (1.62, 2.67)	3.35	2.25 (1.69, 3.00)	1.98	1.77 (1.26, 2.48)
El Mehalla	0.89	1.13 (0.70, 1.82)	14.85	1.66 (1.29, 2.14)	2.66	1.78 (1.33, 2.38)	1.36	1.21 (0.85, 1.72)
Kafr El Zayat	1.06	1.35 (0.77, 2.35)	12.44	1.39 (1.03, 1.89)	2.17	1.46 (1.03, 2.07)	1.44	1.29 (0.85, 1.95)
Samanoud	0.86	1.09 (0.58, 2.04)	11.40	1.28 (0.92, 1.78)	2.12	1.42 (0.98, 2.07)	1.10	0.98 (0.61, 1.58)
El Santa	0.93	1.18 (0.66, 2.11)	11.28	1.26 (0.92, 1.73)	1.99	1.33 (0.93, 1.91)	1.26	1.13 (0.73, 1.74)
Kotour	1.30	1.65 (0.93, 2.90)	9.56	1.07 (0.75, 1.52)	2.06	1.38 (0.94, 2.02)	1.09	0.97 (0.60, 1.58)
Basyoon	1.63	2.06 (1.18, 3.60)	13.81	1.55 (1.11, 2.15)	2.39	1.60 (1.10, 2.34)	1.97	1.76 (1.15, 2.70)
Zefta	0.79	1.00	8.93	1.00	1.49	1.00	1.12	1.00

IRR: Incidence rate ratio; IR: Incidence rate; 95% CI: 95% confidence interval.

Table 5 Age standardized incidence rates by gender in Gharbiah, Egypt and the United States Surveillance Epidemiology and End Results Program

	Gharbiah, Egypt 1999-2007			United States SEER 1999-2001			P value
	Total	Male	Female	Total	Male	Female
Total cases	1364	737	627	55 480	27 892	27 588
Total rate	5.5	6.1	4.9	32.0	37.7	27.4	< 0.00011
< 40 yr	1.3	1.4	1.2	1.2	1.3	1.2
40-59 yr	12.0	12.8	11.2	37.9	43.3	32.8
60-69 yr	19.4	22.5	15.8	154.0	185.4	126.4
> 70 yr	21.2	24.4	18.6	311.3	369.8	270.8

¹χ² test of total age standardized incidence rates, by age group, Gharbiah, Egypt 1999-2007 vs United States Surveillance Epidemiology and End Results Program (SEER) 1999-2001.