Retrospective study of colorectal cancer in Zimbabwe: Colonoscopic and clinical correlates

Table 1 Patient demographics, differences in bowel preparation and extent of examination n (%)

Variable	Black Africansn = 460	Caucasiansn = 1236	Asians/othern = 109	P value
Sex
Male	242 (53)	605 (49)	51 (47)
Female	218 (47)	631 (51)	58 (53)	0.332
Age (yr)
mean ± SD	55 (16)	60 (13)	58 (15)	< 0.001
Bowel preparation regimen
Mannitol 20%	161 (37)	516 (42)	516 (42)
Fleet phosphosoda	255 (59)	687 (56)	682 (56)
Coloprep	16 (4)	30 (2)	30 (2)	0.314
Result of bowel preparation
Poor	84 (18)	134 (11)	14 (13)
Good	200 (44)	520 (42)	40 (37)	< 0.001
Excellent	176 (38)	588 (47)	55 (50)

Table 2 Indications for colonoscopy n (%)

Indication	Black Africansn = 460	Caucasiansn = 1236	Asians/othern = 109	P value
Routine screening, asymptomatic	31 (7)	331 (27)	25 (23)	< 0.001
Previous lesion1	16 (3)	66 (5)	6 (6)	0.273
Haematochezia	174 (38)	234 (19)	22 (20)	< 0.001
Anaemia	68 (15)	47 (4)	17 (16)	< 0.001
Altered bowel habit	201 (44)	543 (44)	37 (34)	0.126
Loss of weight	43 (9)	72 (6)	6 (6)	0.037
Abdominal pain	149 (32)	286 (23)	32 (29)	< 0.001
Family history of bowel cancer	15 (3)	184 (15)	11 (10)	< 0.001

¹Previous adenomatous polyps, colon carcinoma or inflammatory bowel disease. Some patients had more than one indication, thus the summation of the percentages may be more 100%.

Table 3 The endoscopic and histological diagnosis in both symptomatic patients and those referred for a screening procedure n (%)

Primary finding	Black Africansn = 460	Caucasiansn = 1236	Asians/othern = 109	P value
Normal	240 (52)	577 (47)	63 (58)	0.020
Polyps	21 (5)	100 (8)	10 (9)	0.033
Colorectal cancer	44 (10)	41 (3)	2 (2)	< 0.001
Other tumours1	2	1
Diverticulosis	28 (6)	351 (28)	21 (19)	< 0.001
Colitis	34 (7)	29 (2)	2 (2)	< 0.001
Haemorrhoids	65 (14)	124 (10)	9 (8)	0.036
Others	26 (6)	13 (1)	2 (2)	< 0.001

¹One black patient had Kaposi’s sarcoma and one had non-Hodgkin’s lymphoma. There was one Caucasian patient with a mucosa-associated lymphoid tissue lymphoma.

Table 4 The endoscopic and histological diagnoses in symptomatic patients only n (%)

Primary finding	Black Africansn = 413	Caucasiansn = 839	Asians/othern = 78	P value
Normal	205 (50)	337 (40)	42 (54)	0.001
Polyps	17 (4)	70 (8)	8 (10)	0.013
Adenocarcinoma	41 (10)	37 (4)	2 (3)	< 0.001
Other tumours1	2	1
Diverticulosis	27 (7)	245 (29)	14 (18)	< 0.001
Colitis	34 (8)	26 (3)	1 (1)	< 0.001
Haemorrhoids	64 (16)	112 (13)	9 (12)	0.483
Others	23 (6)	11 (1)	2 (3)	< 0.001

¹One black patient had Kaposi’s sarcoma and one had non-Hodgkin’s lymphoma. There was one Caucasian patient with a mucosa-associated lymphoid tissue lymphoma.

Table 5 Differences in the age distribution of patients with colorectal cancer between black Africans and Caucasians n (%)

Age group (yr)	Blacks (n = 44)	Whites (n = 41)	P value
≤ 40	4 (9)	0 (0)
41-50	10 (23)	1 (2)
51-60	18 (27)	8 (20)
> 60	18 (41)	32 (78)	< 0.001

Fisher’s exact test. Asians were excluded from this comparison because the number with colorectal cancer (2) was too small.

Table 6 Predictors of colorectal cancer

Symptoms	Adenocarcinoma (n = 44) OR (95%CI)
	Black Africans (n = 413)	Caucasians (n = 831)
Haematochezia	1.69 (0.89-3.24)	2.44 (1.26-4.75)
Change in bowel habit	0.83 (0.43-1.58)	0.93 (0.47-1.82)
Abdominal pain	0.87 (0.45-1.75)	0.71 (0.33-1.54)
Anaemia	2.73 (1.33-5.61)	6.65 (2.93-15.09)
Loss of weight	3.09 (1.35-7.07)	3.47 (1.52-7.94)
Family history1	3.13 (0.61-16.03)	1.12 (0.26-4.82)

¹Multivariate analysis of clinical predictors of colorectal cancer.