- Email: [email protected]
The outpatient evaluation of hematochezia
Vol. 93, No. 2, 1998 ISSN 0002-9270/98/$19.00 PII SOO02-9270(97)00091-9
THE AMERICAN JOURNAL OF GA~TROE~ROLCGY Copyright 0 1998 by Am. COIL of Gastrcenterology Published by Elsevier Science Inc.
The Outpatient William
Evaluation
of Hematochezia
N. Segal, M.D., Paul D. Greenberg, M.D., Don C. Rockey, M.D., John P. Cello, M.D., and Kenneth R. McQuaid, M.D.
San Francisco Veterans Affairs Hospital and San Francisco General Hospital, San Francisco, California
Oct.
San Francisco,
INTRODUCTION
Objective: The objective of this study was to determine whether specific clinical symptoms associated with hematochezia are predictive of important GI pathology and whether full colonoscopic examination is necessary. Methods: A total of 103 outpatients (2 45 yr) with hematochezia, defined as the passage of bright red blood per rectum, underwent anoscopy and colonoscopy. Before endoscopy, patients completed a detailed interview, quantitating the amount and frequency of bleeding, weight loss, use of aspirin/NSAIDs, change in bowel habits, family history, and prior GI illnesses. Based on this information, physicians were asked to predict whether the bleeding was from a perianal or more proximal site. At colonoscopy, pathology was stratified as either proximal or distal to the sigmoid/descending junction. Substantial pathology was defined as one or more adenomas > 8 mm, carcinoma, or colitis. Results: Anoscopy demonstrated internal and external hemorrhoids in 78 and 29 patients, respectively. On colonoscopy, 36 patients had 43 substantial lesions. Thirty-seven of these lesions were distal to the junction of the descending and sigmoid colons and six were proximal lesions. Four patients had cancer; all were distal lesions. Patients with substantial lesions were more likely to give a history of blood mixed within their stool (p = 0.03), to have more episodes of hematochezia per month @ = O.OOS),and to have a significantly shorter duration of bleeding before medical evaluation 0, = 0.02) than did patients without such lesions. However, the physician’s clinical assessment did not predict reliably which patients were likely to have substantial pathology. Conclusions: In patients with hematochezia, clinicians were unable to distinguish between those patients with and those without significant colonic lesions by history alone. Flexible sigmoidoscopy would have demonstrated most (95%) substantial lesions. The lesions that flexible sigmoidoscopy missed were an unlikely cause of bleeding in this small group of patients. (Am J Gastroenterol 1998;93: 179-182. 0 1998 by Am, COIL of Gastroenterology)
Received June 16, 1997; accepted
University of California
Hematochezia may be a sign of seriousor trivial gastrointestinal pathology; however, there is no consensusas to the proper evaluation of outpatients with this symptom. Much of the debateregarding whether or not colonoscopy is necessarycenterson the concern for proximal colonic neoplasia. For this reason, many practitioners perform a complete colonic evaluation with either a colonoscopy or a flexible sigmoidoscopy and barium enema. Others contend that flexible sigmoidoscopy alone is adequate to elucidate the etiology of bleeding. The literature is divided in its responseto these questions (l-3). The aim of this study was to investigate whether the clinical history is useful in differentiating benign from neoplastic causesof hematochezia, and to compare the endoscopic findings of a limited evaluation with flexible sigmoidoscopy to those of a complete evaluation with colonoscopy. METHODS Study patients Eligible outpatients were evaluated by the Gastroenterology servicesat San Francisco General Hospital and the San Francisco Veterans Affairs Hospital. AIll outpatients at least 45 years old with a history of hematocheziawere eligible to participate in this study. Hematochezia was defined as the passageof bright red blood per rectum (with red blood noted either on or within the stool, on the toilet paper or in the toilet bowl). Patients were enrolled from April 1995through June 1996. The research protocol was approved by the Institutional Review Board at the University of California, San Francisco. Study protocol In addition to complete medical histclry, enrolled patients completed an extensive questionnaire (Fig. 1) in which specific information regarding the nature of the lower gastrointestinal bleeding was obtained. The questionnaire was administered directly by a gastroenteI,ology fellow or an attending physician. Patients were questioned about the onset, duration, and frequency of bleeding. They were also askedto state whether blood was located on the toilet paper
7, 1997.
179
180
SEGAL
AJG - Vol. 93, No. 2, 1998
et al. Questionnaire
for the Outpatient Evaluation of Hematochezia (administered by physician)
Type of Bleeding: *BRBPR (Bright Red Blood Per Rectum) Answer Y or N -blood on toilet paper after having stool: -drops of blood or stream of blood after passage of stool: -blood streaking or coating the outside of stool: -blood soiling of undergarments or bed linens: -blood mixed within stool: *Quantity: Choose from below to indicate the amount of bleeding with each episode On toilet paper only Few drops Tablespoon Cupful Toilet water filled with blood *History of hemorrhoids: *History of diverticulosis: *History of dark black stools: Time/Frequency Number of days since beginning of bleeding: Number of episodes per week or month: Number days since last episode: Answer Y or N to the following: Bowel habits: change in stool frequency or caliber: History of colon polyps: History of colitis: History of prior colonoscopy: History of aspirin or NSAID use within the last 5 days: Unintentional weight loss of 10 lbs or more over the last six months: Family history of colorectal cancer in a first degree relative: Presence of anemia without another known cause (defined as hct < 38 for men, hct < 36 for women) From the clinical history, do you think the bleeding is from hemorrhoids RG. 1. Questionnaire
or in the toilet water, outside or mixed within the stool, and whether it occurred after bowel movements, or soiled undergarments. Those patients whose quantity of bleeding was significant enough to require transfusion or hospital admission were excluded from the study. Additionally, patients with a hemoccult positive stool test without hematochezia were excluded from the study. Based on complete history and physical examination, the clinician was asked to predict whether the bleeding was more likely to have originated from a perianal site (defined as hemorrhoids, fissures, or skin tags), or from a more proximal colorectal source. Anoscopy was performed. The presence or absence of external and internal hemorrhoids, anal fissures, and skin tags was recorded. Hemorrhoids were graded as follows: lo, maintained at proper level within anal canal; 2”, prolapsed with straining, 3”, prolapsed out of the canal and manual reduction necessary; and 4”, prolapsed all the time, and
or a perianal site:? Y or :V
sample.
either cannot be reduced or prolapsed again immediately after reduction. All patients underwent colonoscopy following bowel preparation with either phosphosoda or oral polyethylene balanced solution. Evaluation was considered complete provided that the entire colon, including the cecum, was visualized with adequate bowel preparation. All adenomas were measured with reference to open biopsy forceps before polypectomy and were categorized as large (> 1.6 cm), medium (0.8-1.6 :m), or small (< 0.8 cm). After histopathologic assessment, hyperplastic polyps were classified as normal tissue for th’e purpose of analysis. The presence or absence of cancer, colitis, vascular ectasias, and diverticula were also recorded. For the purposes of this study, “substantial findings” were defined prospectively as adenomatous polyps 2 0.8 cm, colorectal cancer, or colitis. Adenomatous polyps < 0.8 cm and hyperplastic polyps of any size were classified as “nonsubstantial.” All findings
AJG - February
EVALUATION
1998
OF HEMATOCHEZIA
181
TABLE 1
Characteristics of Hematochezia
Duration of Bleeding (yr) Mean time since start of hematochezia Mean number episodes per month Mean time since last episode (days) Characteristic of Bleeding Blood on toilet paper (%) Drops or stream of blood after passage of stool (%) Blood streaking or coating stool (W) Soiling of undergarments (%) Blood mixed within stool (%)
All Patients
No Lesion
Substantial
Lesions
3.0 2 5.3 9.4 2 11.9 40.0 2 63.9
3.9 2 6.3 6.9 -+ 9.0 50.3 ? 74.3
1.3 2 2.3 13.3 2 14.9 22.1 2 34.2
83 47 56 23 36
83 48 62 26 28
84 43 46 19 51
@ Value) (o.oz)* (O.OOE)* (0.03)* (0.83) (0.76) (0.17) (0.59) (0.03)*
* p < 0.05. TABLE 2
were recorded as being “proximal” or “distal” with respect to the junction of the descendingand sigmoid colon, a level that was felt to be the practical extent of a typical flexible sigmoidoscopy. Statistical
analysis
The 2 test was usedto measuredichotomous variables. The Student’s t test was used to measurecontinuous variables. Variables including type and frequency of bleeding, as well as findings on anoscopy and colonoscopy, were compared with the presenceof significant findings. P values < 0.05 were considered significant, and all tests were two-tailed. Ninety-five percent confidence intervals are given when appropriate. RESULTS A total of 103 patients were enrolled in the study. Patients with substantiallesionswere more likely to give a history of blood mixed within their stools (p = 0.03) and had more episodesof hematocheziaper month (p = 0.008) than did patients without such lesions. In addition, patients with substantial lesions had a significantly shorter duration of bleeding before medical evaluation than did other patients (p = 0.02). However, no other historic feature was able to predict substantial pathology in patients (Table 1). The physician’s clinical assessment,which predicted substantial lesionsin 10 of the 36 patients identified, was not a reliable predictor of which patients were likely to have substantial pathology. Anoscopy demonstrated that 29 patients had external hemorrhoids and 78 patients had internal hemorrhoids. Patients without substantiallesions were more likely to have external hemorrhoids than were patients with substantial lesions (p = 0.08), although this difference did not achieve statistical significance. There were 36 patients (35%) with 43 substantiallesions. Thirty-seven of these lesions were distal to the junction of the descending and sigmoid colon and six were proximal lesions (Table 2). Four patients had cancer. These cancers were located in either the rectum or sigmoid colon. Two patients had only proximal lesions without concomitant
Colonoscopy Findings Number Proximal Carcinoma Adenomatous polyps 0.8-1.6 cm > 1.6 cm Colitis * Patients with substantial
findings
of Patients* Distal
Total
0
4
4
5 1 2
20 5 8
25 6 8
(n = 36).
distal lesions,both of which were medium-sizedadenomas. Flexible sigmoidoscopy (evaluation to the junction of the descending and sigmoid colon) would have missed one large (> 1.6 cm), five medium (0.8-1.6 cm), and 20 small (< 0.8 cm) proximal adenomas.No c’ancerswould have been missed. Six proximal substantial lesions would have beenmissedon flexible sigmoidoscopy; however, in four of the six cases,concurrent distal adenorlas would have resulted in subsequentcolonoscopiesthat would have detected these proximal lesions. DISCUSSION The detection of colorectal neoplasm.is of primary concern for physicians evaluating patients with a history of hematochezia.The approach to evaluation of older patients (2 4.5yr) with hematocheziais influenced by two goals: to investigate the etiology of bleeding, and to exclude colorectal neoplasm. Hemorrhoids are believed to be the most common cause of hematocheziain all age groups, accounting for anywhere from 27 to 72% of cases(4, 5). In a :-andomcommunity sampleof 202 personsaged 30 or oldel. with no history of cancer or IBD, 16% of the population r:ported hematochezia in the preceding 6 months (6). Forty-,three percent of the respondentsbelieved that they had “hemorrhoids” basedon the presenceof anal pain, bleeding, protrusion, or itch. In our prospective study of patients with hematochezia, 76% had internal and 28% had external hemorrhoids on anoscopy. Thus, hemorrhoids were extremely prevalent in our
182
SEGAL
et al.
study group; however, it cannot be determined with certainty whether bleeding originated from these lesions. Several studies have evaluated the prevalence of colorectal neoplasm in patients with hematochezia. In a prospective study using colonoscopy, Church evaluated 115 patients with “outlet type bleeding,” defined as bright red blood seen during or after defecation, on the toilet paper, or in the toilet bowl (2). In this subgroup of patients, the positive predictive value for left-sided neoplasm was 34% and for right sided neoplasm, 0.9%. Pines et al. also evaluated 86 patients with rectal bleeding and hemorrhoids over the age of 40 yr (3). They found that 22% of patients had colorectal polyps and 1.2% had cancer. In a large retrospective review of 2200 diagnostic colonoscopies for overt and occult rectal bleeding (526 for occult blood and the remainder for hematochezia), neoplastic polyps and carcinoma were attributed to be the cause of bleeding in 32% and 19% of cases, respectively; 81% of the carcinomas were distal to the splenic flexure (4). In our outpatient study population, which did not have hemodynamically significant bleeding, we found a similar incidence of colorectal neoplasm of any size (41%) but a lower incidence of carcinoma (4%). Whether the patient’s clinical history can reliably distinguish hemorrhoidal or perianal bleeding from bleeding caused by a colorectal cancer or polyp is important from a management standpoint. Mant et al. evaluated 145 patients, age 40 years or older, who underwent a colonic evaluation for rectal bleeding (7). Of the historical features obtained, there was an increased probability of colorectal cancer only in those patients who reported blood mixed with their feces. Similarly, our study found that there were more substantial findings on colonoscopy in those patients who reported blood mixed within the stool. Additionally, we found that for patients with hematochezia, more frequent bleeding and a shorter time from onset of bleeding to medical evaluation were also individually associated with a higher probability of finding substantial pathology on colonic examination. However, the physician’s global assessment did not appear useful in differentiating those patients with a perianal source of bleeding from those who had proximal pathology. Helfand et al. had similar findings when evaluating rectal bleeding in a primary care population (1). Despite the lack of physician assessment to predict sub-
AJG - Vol. 93, No. 2, 1998 stantial pathology, flexible sigmoidoscopy would have detected 95% of substantial lesions. Indeed, no patient had a proximal cancer, whereas only one had a proximal large adenoma. It is our practice to perform colonoscopy on all patients found to have adenomatous polyps on flexible sigmoidoscopy. However, in this study, only two patients had substantial lesions (medium-sized polyps) without distal polyps. Therefore, flexible sigmoidoscopy ultimately would have missed only a small number (2%) of proximal lesions in patients without substantial distal lesions. Moreover, the lesions that sigmoidoscopy would have missed were either small or medium-sized adenomas, and probably not the source of bleeding. In summary, although some historical features suggest a higher probability of finding colonic pathology, clinical features taken together are not reliable in predicting those patients who have only perianal disease. If the goal is to evaluate the etiology of hematochezia in outpatients, then flexible sigmoidoscopy will detect almost all substantial colonic lesions. The lesions that flexible sigmoidoscopy missed were unlikely to be the cause of the bleeding in this small group of patients, and likely reflect the underlying prevalence of proximal adenomas in, a Western adult population. Reprint requests and correspondence: Witherspoon Street, Suite 230, Princeton,
William N. Segal, M.D., NJ 08542.
281
REFERENCES 1. Helfand M, et al. History of visible rectal bleeding in a primary care population. JAMA 1997;277:4&8. 2. Church JM. Analysis of the colonoscop c findings in patients with rectal bleeding according to the pattern of their presenting symptoms. Dis Colon Rectum 1991;34:391-5. 3. Pines A, Shemesh E, Bat L. Prolonged ret tal bleeding associated with hemorrhoids: The diagnostic contribution of colonoscopy. South Med J 1987;80:313-4. Shinya H, Cwem M, Wolf G. Colonoscopic diagnosis and management of rectal bleeding. Surg Clin N Am 1982;62:897-903. Goulston KJ, Cook I, Dent OF. How impol-tant is rectal bleeding in the diagnosis of bowel cancer and polyps?.Lancet 1986;2:261-4.Dent OF, Goulston KJ, Zubrzvcki J, et al. Bowel svmutoms in an apparently well population. Di6 Colon Rectum 1986;i9:i43-7. Mant A, Bokey EL, Chapuis PH, et al. Rectal bleeding: Do other symptoms aid in diagnosis? Dis Colon Rectum 1989;32:191-5.
THE AMERICAN JOURNAL OF GA~TROE~ROLCGY Copyright 0 1998 by Am. COIL of Gastrcenterology Published by Elsevier Science Inc.
The Outpatient William
Evaluation
of Hematochezia
N. Segal, M.D., Paul D. Greenberg, M.D., Don C. Rockey, M.D., John P. Cello, M.D., and Kenneth R. McQuaid, M.D.
San Francisco Veterans Affairs Hospital and San Francisco General Hospital, San Francisco, California
Oct.
San Francisco,
INTRODUCTION
Objective: The objective of this study was to determine whether specific clinical symptoms associated with hematochezia are predictive of important GI pathology and whether full colonoscopic examination is necessary. Methods: A total of 103 outpatients (2 45 yr) with hematochezia, defined as the passage of bright red blood per rectum, underwent anoscopy and colonoscopy. Before endoscopy, patients completed a detailed interview, quantitating the amount and frequency of bleeding, weight loss, use of aspirin/NSAIDs, change in bowel habits, family history, and prior GI illnesses. Based on this information, physicians were asked to predict whether the bleeding was from a perianal or more proximal site. At colonoscopy, pathology was stratified as either proximal or distal to the sigmoid/descending junction. Substantial pathology was defined as one or more adenomas > 8 mm, carcinoma, or colitis. Results: Anoscopy demonstrated internal and external hemorrhoids in 78 and 29 patients, respectively. On colonoscopy, 36 patients had 43 substantial lesions. Thirty-seven of these lesions were distal to the junction of the descending and sigmoid colons and six were proximal lesions. Four patients had cancer; all were distal lesions. Patients with substantial lesions were more likely to give a history of blood mixed within their stool (p = 0.03), to have more episodes of hematochezia per month @ = O.OOS),and to have a significantly shorter duration of bleeding before medical evaluation 0, = 0.02) than did patients without such lesions. However, the physician’s clinical assessment did not predict reliably which patients were likely to have substantial pathology. Conclusions: In patients with hematochezia, clinicians were unable to distinguish between those patients with and those without significant colonic lesions by history alone. Flexible sigmoidoscopy would have demonstrated most (95%) substantial lesions. The lesions that flexible sigmoidoscopy missed were an unlikely cause of bleeding in this small group of patients. (Am J Gastroenterol 1998;93: 179-182. 0 1998 by Am, COIL of Gastroenterology)
Received June 16, 1997; accepted
University of California
Hematochezia may be a sign of seriousor trivial gastrointestinal pathology; however, there is no consensusas to the proper evaluation of outpatients with this symptom. Much of the debateregarding whether or not colonoscopy is necessarycenterson the concern for proximal colonic neoplasia. For this reason, many practitioners perform a complete colonic evaluation with either a colonoscopy or a flexible sigmoidoscopy and barium enema. Others contend that flexible sigmoidoscopy alone is adequate to elucidate the etiology of bleeding. The literature is divided in its responseto these questions (l-3). The aim of this study was to investigate whether the clinical history is useful in differentiating benign from neoplastic causesof hematochezia, and to compare the endoscopic findings of a limited evaluation with flexible sigmoidoscopy to those of a complete evaluation with colonoscopy. METHODS Study patients Eligible outpatients were evaluated by the Gastroenterology servicesat San Francisco General Hospital and the San Francisco Veterans Affairs Hospital. AIll outpatients at least 45 years old with a history of hematocheziawere eligible to participate in this study. Hematochezia was defined as the passageof bright red blood per rectum (with red blood noted either on or within the stool, on the toilet paper or in the toilet bowl). Patients were enrolled from April 1995through June 1996. The research protocol was approved by the Institutional Review Board at the University of California, San Francisco. Study protocol In addition to complete medical histclry, enrolled patients completed an extensive questionnaire (Fig. 1) in which specific information regarding the nature of the lower gastrointestinal bleeding was obtained. The questionnaire was administered directly by a gastroenteI,ology fellow or an attending physician. Patients were questioned about the onset, duration, and frequency of bleeding. They were also askedto state whether blood was located on the toilet paper
7, 1997.
179
180
SEGAL
AJG - Vol. 93, No. 2, 1998
et al. Questionnaire
for the Outpatient Evaluation of Hematochezia (administered by physician)
Type of Bleeding: *BRBPR (Bright Red Blood Per Rectum) Answer Y or N -blood on toilet paper after having stool: -drops of blood or stream of blood after passage of stool: -blood streaking or coating the outside of stool: -blood soiling of undergarments or bed linens: -blood mixed within stool: *Quantity: Choose from below to indicate the amount of bleeding with each episode On toilet paper only Few drops Tablespoon Cupful Toilet water filled with blood *History of hemorrhoids: *History of diverticulosis: *History of dark black stools: Time/Frequency Number of days since beginning of bleeding: Number of episodes per week or month: Number days since last episode: Answer Y or N to the following: Bowel habits: change in stool frequency or caliber: History of colon polyps: History of colitis: History of prior colonoscopy: History of aspirin or NSAID use within the last 5 days: Unintentional weight loss of 10 lbs or more over the last six months: Family history of colorectal cancer in a first degree relative: Presence of anemia without another known cause (defined as hct < 38 for men, hct < 36 for women) From the clinical history, do you think the bleeding is from hemorrhoids RG. 1. Questionnaire
or in the toilet water, outside or mixed within the stool, and whether it occurred after bowel movements, or soiled undergarments. Those patients whose quantity of bleeding was significant enough to require transfusion or hospital admission were excluded from the study. Additionally, patients with a hemoccult positive stool test without hematochezia were excluded from the study. Based on complete history and physical examination, the clinician was asked to predict whether the bleeding was more likely to have originated from a perianal site (defined as hemorrhoids, fissures, or skin tags), or from a more proximal colorectal source. Anoscopy was performed. The presence or absence of external and internal hemorrhoids, anal fissures, and skin tags was recorded. Hemorrhoids were graded as follows: lo, maintained at proper level within anal canal; 2”, prolapsed with straining, 3”, prolapsed out of the canal and manual reduction necessary; and 4”, prolapsed all the time, and
or a perianal site:? Y or :V
sample.
either cannot be reduced or prolapsed again immediately after reduction. All patients underwent colonoscopy following bowel preparation with either phosphosoda or oral polyethylene balanced solution. Evaluation was considered complete provided that the entire colon, including the cecum, was visualized with adequate bowel preparation. All adenomas were measured with reference to open biopsy forceps before polypectomy and were categorized as large (> 1.6 cm), medium (0.8-1.6 :m), or small (< 0.8 cm). After histopathologic assessment, hyperplastic polyps were classified as normal tissue for th’e purpose of analysis. The presence or absence of cancer, colitis, vascular ectasias, and diverticula were also recorded. For the purposes of this study, “substantial findings” were defined prospectively as adenomatous polyps 2 0.8 cm, colorectal cancer, or colitis. Adenomatous polyps < 0.8 cm and hyperplastic polyps of any size were classified as “nonsubstantial.” All findings
AJG - February
EVALUATION
1998
OF HEMATOCHEZIA
181
TABLE 1
Characteristics of Hematochezia
Duration of Bleeding (yr) Mean time since start of hematochezia Mean number episodes per month Mean time since last episode (days) Characteristic of Bleeding Blood on toilet paper (%) Drops or stream of blood after passage of stool (%) Blood streaking or coating stool (W) Soiling of undergarments (%) Blood mixed within stool (%)
All Patients
No Lesion
Substantial
Lesions
3.0 2 5.3 9.4 2 11.9 40.0 2 63.9
3.9 2 6.3 6.9 -+ 9.0 50.3 ? 74.3
1.3 2 2.3 13.3 2 14.9 22.1 2 34.2
83 47 56 23 36
83 48 62 26 28
84 43 46 19 51
@ Value) (o.oz)* (O.OOE)* (0.03)* (0.83) (0.76) (0.17) (0.59) (0.03)*
* p < 0.05. TABLE 2
were recorded as being “proximal” or “distal” with respect to the junction of the descendingand sigmoid colon, a level that was felt to be the practical extent of a typical flexible sigmoidoscopy. Statistical
analysis
The 2 test was usedto measuredichotomous variables. The Student’s t test was used to measurecontinuous variables. Variables including type and frequency of bleeding, as well as findings on anoscopy and colonoscopy, were compared with the presenceof significant findings. P values < 0.05 were considered significant, and all tests were two-tailed. Ninety-five percent confidence intervals are given when appropriate. RESULTS A total of 103 patients were enrolled in the study. Patients with substantiallesionswere more likely to give a history of blood mixed within their stools (p = 0.03) and had more episodesof hematocheziaper month (p = 0.008) than did patients without such lesions. In addition, patients with substantial lesions had a significantly shorter duration of bleeding before medical evaluation than did other patients (p = 0.02). However, no other historic feature was able to predict substantial pathology in patients (Table 1). The physician’s clinical assessment,which predicted substantial lesionsin 10 of the 36 patients identified, was not a reliable predictor of which patients were likely to have substantial pathology. Anoscopy demonstrated that 29 patients had external hemorrhoids and 78 patients had internal hemorrhoids. Patients without substantiallesions were more likely to have external hemorrhoids than were patients with substantial lesions (p = 0.08), although this difference did not achieve statistical significance. There were 36 patients (35%) with 43 substantiallesions. Thirty-seven of these lesions were distal to the junction of the descending and sigmoid colon and six were proximal lesions (Table 2). Four patients had cancer. These cancers were located in either the rectum or sigmoid colon. Two patients had only proximal lesions without concomitant
Colonoscopy Findings Number Proximal Carcinoma Adenomatous polyps 0.8-1.6 cm > 1.6 cm Colitis * Patients with substantial
findings
of Patients* Distal
Total
0
4
4
5 1 2
20 5 8
25 6 8
(n = 36).
distal lesions,both of which were medium-sizedadenomas. Flexible sigmoidoscopy (evaluation to the junction of the descending and sigmoid colon) would have missed one large (> 1.6 cm), five medium (0.8-1.6 cm), and 20 small (< 0.8 cm) proximal adenomas.No c’ancerswould have been missed. Six proximal substantial lesions would have beenmissedon flexible sigmoidoscopy; however, in four of the six cases,concurrent distal adenorlas would have resulted in subsequentcolonoscopiesthat would have detected these proximal lesions. DISCUSSION The detection of colorectal neoplasm.is of primary concern for physicians evaluating patients with a history of hematochezia.The approach to evaluation of older patients (2 4.5yr) with hematocheziais influenced by two goals: to investigate the etiology of bleeding, and to exclude colorectal neoplasm. Hemorrhoids are believed to be the most common cause of hematocheziain all age groups, accounting for anywhere from 27 to 72% of cases(4, 5). In a :-andomcommunity sampleof 202 personsaged 30 or oldel. with no history of cancer or IBD, 16% of the population r:ported hematochezia in the preceding 6 months (6). Forty-,three percent of the respondentsbelieved that they had “hemorrhoids” basedon the presenceof anal pain, bleeding, protrusion, or itch. In our prospective study of patients with hematochezia, 76% had internal and 28% had external hemorrhoids on anoscopy. Thus, hemorrhoids were extremely prevalent in our
182
SEGAL
et al.
study group; however, it cannot be determined with certainty whether bleeding originated from these lesions. Several studies have evaluated the prevalence of colorectal neoplasm in patients with hematochezia. In a prospective study using colonoscopy, Church evaluated 115 patients with “outlet type bleeding,” defined as bright red blood seen during or after defecation, on the toilet paper, or in the toilet bowl (2). In this subgroup of patients, the positive predictive value for left-sided neoplasm was 34% and for right sided neoplasm, 0.9%. Pines et al. also evaluated 86 patients with rectal bleeding and hemorrhoids over the age of 40 yr (3). They found that 22% of patients had colorectal polyps and 1.2% had cancer. In a large retrospective review of 2200 diagnostic colonoscopies for overt and occult rectal bleeding (526 for occult blood and the remainder for hematochezia), neoplastic polyps and carcinoma were attributed to be the cause of bleeding in 32% and 19% of cases, respectively; 81% of the carcinomas were distal to the splenic flexure (4). In our outpatient study population, which did not have hemodynamically significant bleeding, we found a similar incidence of colorectal neoplasm of any size (41%) but a lower incidence of carcinoma (4%). Whether the patient’s clinical history can reliably distinguish hemorrhoidal or perianal bleeding from bleeding caused by a colorectal cancer or polyp is important from a management standpoint. Mant et al. evaluated 145 patients, age 40 years or older, who underwent a colonic evaluation for rectal bleeding (7). Of the historical features obtained, there was an increased probability of colorectal cancer only in those patients who reported blood mixed with their feces. Similarly, our study found that there were more substantial findings on colonoscopy in those patients who reported blood mixed within the stool. Additionally, we found that for patients with hematochezia, more frequent bleeding and a shorter time from onset of bleeding to medical evaluation were also individually associated with a higher probability of finding substantial pathology on colonic examination. However, the physician’s global assessment did not appear useful in differentiating those patients with a perianal source of bleeding from those who had proximal pathology. Helfand et al. had similar findings when evaluating rectal bleeding in a primary care population (1). Despite the lack of physician assessment to predict sub-
AJG - Vol. 93, No. 2, 1998 stantial pathology, flexible sigmoidoscopy would have detected 95% of substantial lesions. Indeed, no patient had a proximal cancer, whereas only one had a proximal large adenoma. It is our practice to perform colonoscopy on all patients found to have adenomatous polyps on flexible sigmoidoscopy. However, in this study, only two patients had substantial lesions (medium-sized polyps) without distal polyps. Therefore, flexible sigmoidoscopy ultimately would have missed only a small number (2%) of proximal lesions in patients without substantial distal lesions. Moreover, the lesions that sigmoidoscopy would have missed were either small or medium-sized adenomas, and probably not the source of bleeding. In summary, although some historical features suggest a higher probability of finding colonic pathology, clinical features taken together are not reliable in predicting those patients who have only perianal disease. If the goal is to evaluate the etiology of hematochezia in outpatients, then flexible sigmoidoscopy will detect almost all substantial colonic lesions. The lesions that flexible sigmoidoscopy missed were unlikely to be the cause of the bleeding in this small group of patients, and likely reflect the underlying prevalence of proximal adenomas in, a Western adult population. Reprint requests and correspondence: Witherspoon Street, Suite 230, Princeton,
William N. Segal, M.D., NJ 08542.
281
REFERENCES 1. Helfand M, et al. History of visible rectal bleeding in a primary care population. JAMA 1997;277:4&8. 2. Church JM. Analysis of the colonoscop c findings in patients with rectal bleeding according to the pattern of their presenting symptoms. Dis Colon Rectum 1991;34:391-5. 3. Pines A, Shemesh E, Bat L. Prolonged ret tal bleeding associated with hemorrhoids: The diagnostic contribution of colonoscopy. South Med J 1987;80:313-4. Shinya H, Cwem M, Wolf G. Colonoscopic diagnosis and management of rectal bleeding. Surg Clin N Am 1982;62:897-903. Goulston KJ, Cook I, Dent OF. How impol-tant is rectal bleeding in the diagnosis of bowel cancer and polyps?.Lancet 1986;2:261-4.Dent OF, Goulston KJ, Zubrzvcki J, et al. Bowel svmutoms in an apparently well population. Di6 Colon Rectum 1986;i9:i43-7. Mant A, Bokey EL, Chapuis PH, et al. Rectal bleeding: Do other symptoms aid in diagnosis? Dis Colon Rectum 1989;32:191-5.