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KNOWLEDGE AND ATTITUDES OF GASTROENTEROLOGISTS IN COLORECTAL CANCER OWENDENT',MARKBASSETT~ AND KERRY GOuLSTON3

Gastroenterology Unit, Woden Valley Hospital, Canberra A group of 73 gastroenterological specialists (36 physlcians, 25 surgeons, 12 trainers) completed a detalled questionnaire on their knowledge of and attltudes to coiorectai cancer. A surprising unawareness of recent developments in colorectal cancer was apparent. Although responsesto individual questions varied throughout the three groups, overall knowledge and attltudes on colorectal cancer were not related to age and years since graduation, and were not dlfferent in the three groups. Thls study suggests failure of tradltlonal methods of continuing medical educatlon, and has practical implications for any screening programme designed to detect early colorectal cancer.

CANCER of the colon and rectum (C.C.) is the commonest malignancy in Australia with the exception of skin cancer (New South Wales Central Cancer Registry, 1972). The death rate is high, with about 3,000 deaths from this malignancy each year, almost equalling the number of deaths from motor vehicle accidents. There has been almost no improvement in the survival of patients with colorectal cancer in the past 25 years (Bassett and Goulston, 1978). Currently, there is noevidence that methods of prevention or improved therapeutic techniques improve survival. Hope forthe future lies in earlier diagnosis of colorectal cancer, either by decreasing delay in diagnosis of the symptomatic case or by early detection. Early detection may be achieved by detecting asymptomatic cases or by selectively screening high-risk groups. The success of any screening programme would depend on both the willingness of doctors to carry it out and their awareness of recent advances in this field. The purpose of this study was to assess the knowledge and attitudes of a group of gastroenterological physipians and surgeons. Because of the nature of their speciality, this group would be expected to have a higher level of knowledge in this area than other groups of doctors. METHOD Questionnaires were prepared for distribution to participants attending the May 1977 Joint Meeting ' Lecturer

in Sociology, Australian National University. Gastroenterology Registrar. Woden Valley Hospital. Director, Gastroenterology Unit, Woden Valley Hospital.

Reprints: Or Kerry Goulston. Gastroenterology Unit, Woden Valley Hospital, P.O. Box 11, Woden. A.C.T. 2606.

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of the Gastroenterological Society of Australia and the Surgical Research Society of Australasia in Melbourne. Unfortunately, an air traffic controllers' strike drastically reduced attendance at this m e e t i n g , a n d i n c o n s e q u e n c e o n l y 43 questionnaires were completed. These responses were supplemented by a further 30 obtained from members of gastroenterology units in major hospitals in Australia. Clearly the sample is in no sense a probability sample, and hence statistical estimation and hypothesis-testing procedures cannot legitimately be used, and no statistical significance levels are presented with the results. We cannot claim that these findings are representative of gastroenterologists in Australia, and we do not attempt to generalize our results beyond the group of 73 doctors who completed the questionnaire. It must be. noted, however, that the method of selection probably biases the sample towards the most concerned gastroenterological specialists, and the results presented here are probably indicative of levels of knowledge, opinion, and practice, among the country's most enlightened practitioners in this field. On the other hand, geographically isolated gastroenterologists and. those members of the Society who are not regular attenders at meetings are probably grossly u nder-represented. The sample included 36 physicians (mean age 42 years, S.D. 7.8),25 surgeons (mean age 42.6years, S.D. 7.9), and 12 gastroenterology trainees (mean age 29.3 years, S.D. 1.4). Gastroenterological trainees are physicians in advanced training in gastroenterology in the F.R.A.C.P. training programme. The mean period since graduation was 33 1

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18.6 years for the physicians, 19.1 years for the surgeons, and 5.2 years for the gastroenterology trainees. Because of the small sample size, particularly of gastroenterology trainees, caution is necessary in drawing comparisons between the three groups: physicians, surgeons, and trainees. As percentages are computed over a total of only 12 trainees, a single trainee changing his mind on a question will alter the overall percentage distribution by 8.3%. Comparable figures for the 25 surgeons and 36 physicians are 4% and 2.8% respectively. Thus percentage differences between the categories may not be “true” differences, but merely artefacts of sample size. Issues covered in the qeustionnaire were concerned with factual knowledge and attitudes or opinions regarding colorectal cancer.

RESULTS Knowledge Questions Eighteen questions were included toestablish the level of knowledge about C.C. among these clinicians. Some of these questions were presented as multiple choice questions, while others were presented as statements which could be rated as correct or incorrect by the respondent. Overall, only 38% of respondents (Table 1) were aware that recent U.S. reviews areclaiming that C.C is now the most common newly diagnosed cancer in the U.S.A. (Winawer et alii, 1976). C.C. is also the commonest malignancy in Australia, excluding skin cancer (New South Wales Cancer Registry, 1972), and yet overall only 16% were aware of this. The response to this particular question, and also the preceding one, could have been confused by the knowledge that the incidence of skin cancer is TABLE 1 ~

% % % % Physicians Surgeons Trainees Overall 1.

Recent U S . reviews - C.C. Incidence No response 0 Most common 42 2nd most common 44 11 3rd most common 4th most common 3

12 36 52 0 0

0 33 50 17 0

2. C.C. Incidence in Australia Most Common 2nd most common 3rd most common 4th most common Don’f known

11 47 31 8 3

28 52 16 4 0

8 58 25 0

3. Overall five-year Survival 20% 40% 60% 80%

22 67 8 3

16 52 32 0

0 83 17

332

8

0

4 38 46

a 2

16 51 25 5 3

16 65 18 1

higher (although unreported in most cancer statistics). However, taking this possibility into account, overall only 67% placed C.C. in the first or second rank of incidence. Surprisingly, one-third of the total respondents either placed C.C. at or below the third rank, or were unaware of its level of incidence. This mistake was made more by physicians (42%) and trainess (33%) than surgeons (20%). Responsesto a question on prognosis indicated a widespread and unwarranted degree of pessimism. This question was ambiguous in that it could be construed as either overall survival (actual average is about 40%) (Miller, 1973; Mazabi etalii, 1976), or postoperative survival (actual average is 60%) (Hughes, 1976). However, 22% of physicians and i 6 % of surgeons placed the five-year survival as low as 20%. Gastroenterological trainees showed the highest level of knowledge on this question, all giving either 40% or 60% as the five-year survival rate. Over half the respondents felt that patient delay in presenting to the clinician had not lessenedover the last 20 years, and similarly an almost equal number believed that medical delay had not decreased (Table 2). Clearly, theefficacy of public and medical TABLE 2 k % % % Physicians Surgeons Trainees Overall

Over the past 20 years: 4. Patient delay has not decreased

58

56

67

59

Doctor delay has not decreased

56

56

58

56

61

76

75

69

5.

6. five-year survival has not improved

education in reducing the time lag between onset of symptoms and diagnosis is disputed. The hard fact is that there has been no observed change in patient and doctor delay over 20 years (Hackett et alii, 1973). Delay in diagnosis of more than four months occurs in 20% to 50% of patients presenting with symptoms of C.C. (Peltokallio, 1965; Cohen and Davis, 1975; Pheils et alii, 1976). In two-thirds, the delay is due to failure of the patient to recognize the significance of symptoms (either through lack of knowledge, or conscious or subconscious denial), while the remainder are due to failure of the doctor to make the diagnosis and order the appropriate investigations. Approximately 40% of physicians considered that the prognosis of C.C. had improved over the last 20 years. Surgeons and trainees were more correct in AUST.N.Z. J. SURG. V0~.48-No.3,

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assessing the lack of improvement in five-year survival rates. There has been almost no improvement in survival of patients with C.C. in the past 25 years (Bassett and Goulston, 1978). There is now considerable evidence that the risk of C.C. in first-degree relatives is increased fourfold over that in the general population (Lovett, 1976; Dunstone and Knaggs, 1972). However, only 27% of respondents overall indicated a three or four times increased risk i n first-degree relatives (Table 3). TAELE 3 96 % W % Physicians Surgeons Trainees Overall 7

8

Incidence of C C in first degree relatives No response Same as in general population Twice Three times Four times Don't know

3

0

0

2

22 56 17 2 0

24 44 20 12 0

25 25 25 17

8

23 47 19 8 1

Screen relatives

11

12.

8

11

Twenty-three percent of all respondents considered there to be no greater risk in first-degree relatives. This has considerable importance i n history taking and in early detection of C.C. On the other hand, despite the fact that 74% were aware that the risk of C.C. in first-degree relatives is increased over that in the general population, only 11% overall recommended screening of this high-risk group. This may reflect the lack of agreement on the best method of screening. TABLE 4 % % % % Physicians Surgeons Trainees Overall

9. Adenomatous polyps are premalignant

72

88

75

78

10. Malignancy varies with size of polyp

81

80

67

78

11. Would remove 1-cm rectal polyp

78

96

75

84

12. Would submit 1-cm rectal polyp to biopsy

58

28

58

48

13. Would check rest of colon

94

88

92

92

6 6 14 33 17 17 8 0

0 24 12 24 20 16 0 4

8 0 0 42 17 17 17 0

4 11 11 32 18 16 7

14.

Probability of other polyps in colon: No response 5% 10% 20% 30% 40% 60% Don't know

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Despite initial controversy, there is now good evidence that the majority of C.C. arise from adenomatous polyps (Morson, 1974; Muto et alii, 1975). Overall, 78% of the group questioned were aware that colonic polypsare premalignant and that the incidence of malignancy varies with the size of the polyp (Table4). It wasdisturbing to find that28% of the physicians did not consider polyps to be premalignant. Not all respondents indicated they would remove a one-centimetre rectal polyp, perhaps reflecting the current controversy on the management of polyps. While most authorities agree that polyps greater than 1.5-2 cm should be excised, there is controversy over the management of polyps less than 1.5 Cm in diameter (Marshak et alii, 1976; Winawer, 1976). There is no place for biopsy of a polyp, as this may miss the area of malignancy, and may be difficult to interpret histologically (Morson, 1977). Surprisingly, 58% of physicians and trainees indicated they would subject a one-centimetre rectal polyp to biopsy. The finding of one adenomatous polyp should initiate a search for further polyps in the colon, as there is a 20% to 40% incidence of synchronous polypoid lesions (Winawer, 1976; Marshak et alii, 1976; Morson, 1974). Most (92%) respondents indicated that they would check the rest of the colon for further polyps. Two-thirds (66%) were correct in their estimation of the synchronous incidence of polyps. There was a tendency for surgeons to be more often correct than physicians and trainees with regard to management of colonic polyps. This may be due to the facts that much of the recent literature on adenomatous polyps has appeared in surgical journals, and that polyps have traditionally been treated by surgeons. Accurate knowledge of the probability of a second (metachronous) C.C. occurring after successful resection is lacking, with only half overall placing it at three or four times the risk in the general population (Table 5). Morson (1974) and Winawer (1976) have estimated a threefold increase in risk annually, or, i f polyps were present in the colon at the time of resection, a sixfold increase in risk (Winawer et alii, 1976; Morson, 1974). Surgeons displayed a more aggressive approach, with 80% recommending regular screening for metachronous C.C. in a patient who has had a successful resection for C.C. A surprisingly low percentage of physicians (56%) and trainees (50%) would do so, despite their knowledge.

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COLORECTAL CANCER TABLE 5 I k % % Physicians Surgeons Trainees Overall 15. Chanceof metachronous C.C. No response Same as in general population Twice Three times Four times Don’t know 16. Recommend regular screening for metachronous C.C.

0

4

8

8

8

0

39 22 31 0

36 12 40

42 25 17 8

32

0

56

80

50

63

3 7 36 19 1

Astonishingly, 34% overall thought that 40% or 60% of C.C. could be felt on rectal examination (physicians 25%, surgeons 48%. trainees 34%) (Table 6). Approximately a third of physicians and trainees selected the correct answer (10%) (Berg and Howell, 1974). whilst only 12%of surgeons did so. Similarly, nearly half (48%) of all respondents optimistically, yet incorrectly, thought that sigmoidoscopy would reach 60% or 75% of C.C. Only a third (38%)overall gave the correct answer of 40%. Twenty per cent of surgeons thought that sigmoidoscopy could diagnose 75% of C.C.! A review of five recent studies indicates that 37% to 49% (mean 41%) of cancers lie in the rectum and rectosigmoid area (Bassett and Goulston, 1978), and hence it would appear impossible for more than 40% to 50% of cancers t o be seen on sigmoidoscopy. This is confirmed by Pheils et alii, who noted that 43% of 200 cancers were seen on sigmoidoscopy (Pheils et alii, 1976). The overall average percentage giving the correct answer to the 18 knowledge questions was 54%with TABLE6 % % % % Physicians Surgeons Trainees Overall

17. Percentage of C.C. within reach of finger 5%

0

10% 20% 40% 60%

36 39 22 3

4 12 36 48 0

3 17 44 31 5

4 4 32 40 20

0

1

33 33 34 0

28 37 33 1

18. Percentage of C.C. within reach of sigmoidoscope

15% 20% 40% 60% 75%

334

0

3

8

11

34 50 8

36 37 11

no difference among the three groups (physicians 53%, surgeons 55%, and gastroenterology trainees 53%).Considering answers which are indisputably false, the overall incorrect percentage was 23%, again with no difference among the three groups (physicians 26%surgeons 21%,and trainees 26%). A procedure commonly used in psychological and social measurement is the combination of many individual items into an additive scale representing some wide concept such as attitude or knowledge (Nunnally, 1967). Such a multi-item scale will tend to have greater reliability than the individual items alone because unique variance attributable to individual items cancels out, whereas common variance between items tends to be reinforced. The 18 questions discussed above were summed into such a scale, giving a weight of 2 for a correct response and a weight of 1 for an incorrect response. The distribution of knowledge scale scores thus obtained for individuals was approximately normal, and ranged from 21 to 35, with a mean of 28.3 and a standard deviation of 2.87. These scores, of course, may only be interpreted in a relative sense and have no absolute meaning. As might be anticipated from the earlier finding that physicians, surgeons, and trainees did not differ with respect to average proportion of correct answers, the mean knowledge scale scores were found not t o differ between these three subcategories (physicians 27.9, surgeons 28.9, trainees 28.2). Furthermore, the knowledge scale means did not differ according to whether or not the respondent had a first-degree relative with C.C., suggesting that close personal contact with C.C. has no influence on the acquisition of knowledge. Taking this analysis of scale scores a step further, knowledge was plotted against age and years since graduation (which are themselves highly correlated - Pearson r = 0.87) and no association whatever was detected. Knowledge of C.C. was not related to age or time since graduation, which is a finding of considerable interest. Opinion Questions Five questions were included to assess attitude and opinion. There is a propounced feeling that the general public have a pessimistic appreciation of the C.C. survival rate. Over half (59%)thought the public placed the five-year survival as low as 20%, reflecting the general pessimism associated with a “cancer” diagnosis. Only 25% felt that the public place five-year survival in the 40% to 60% range. Approximately 80%of these doctors felt that less than half the public regularly inspect their faeces. The general public is told that blood in the motions AUST.

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is an early sign of C.C., and doctors are taught to enquire for this symptom - yet most of these clinicians felt that half the public could not reliably answer this question. To our knowledge, no survey has been carried out to answer this question. Overall, 86% of these clinicians expressed optimism that earlier diagnosis would improve the five-year survival (Table 7). Whilst it is controversial whether earlier diagnosis of symtomatic patients TABLE 7 % % % % Physicians Surgeons Trainees Overall

Earlier diagnosis would lead to better five-year survival

89

60

92

86

Colonoscopic removal of polyps would reduce C.C. incidence

61

76

67

67

Medical profession should educate public more regarding C.C. symptoms

66

63

85

68

Emphasis on undergraduate teaching of early C.C. diagnosis is adequate

50

60

42

52

Emphasis on postgraduate teaching of early C.C. diagnosis is adequate

56

56

42

53

will improve prognosis (Hughes, 1977), there is evidence that mass screening of the asymptomatic population will detect C.C. at a more localized stage (Winawer et alii, 1977; Bond and Gilbertson, 1977) and result in an improved lifeexpectancy (Tydeman et alii, 1977). Two-thirds of these specialists were of the opinion that colonoscopic removal of polyps would reduce the incidence of C.C. It is interesting that when this question was correlated with the question “are adenomatous polyps prernalignant?”, 23% of respondents who considered polyps premalignant did not favour prophylactic removal to lower the incidence of C.C. The majority of respondents considered that the medical profession should educate the public more about C.C. symptoms (Table 7). Two questions on the emphasis on teaching of early diagnosis to doctors produced verysimilar results. Perhaps most interesting was the opinion of nearly half of the respondents that both undergraduate and postgraduate education dealing with early diagnosis of C.C. were inadequate. As with the knowledge items, the opinion questions can be summed into a scale, though with so few questions and no opportunity to establish AUST.

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validity the outcome must be treated with caution. The idea behind the method used in combining these items is that respondents may be rated as having an “optimistic-progressive’’ attitude on the one hand as against a “pessimistic-conservative” attitude on the other. The “optimistic-progressive” position is defined by the following responses: (a) Earlier diagnosis would lead to better five-year survival; (b) Colonoscopic removal of polyps would reduce C.C. incidence; (c) An optimistic view of public appreciation of C.C. survival rates (greater or equal to 40%); (d) An optimistic view of examination of the faeces by the public (greater or equal to 50%); (e) The medical profession should educate the public more regarding C.C. symptoms; (f) Emphasis on undergraduate teaching of early C.C. diagnosis is inadequate; and (9) Emphasis on postgraduate teaching of early C.C. diagnosis is inadequate. The individual scale scores thus obtained were approximately normally distributed and ranged from 8 to 14, with a mean of 11.12 and a standard deviation of 1.42. As with the knowledge scale, these scale scores have relative significance only. Mean opinion scale scores showed negligible differences among subcategories of respondents (physicians 10.9, surgeons 112,trainees 11.5) and were not influenced by whether or not the respondent had a first-degree relative with C.C. It appears that physicians, surgeons, and gastroenterology trainees share about the same level of “progressivism-optimism’’ and that this characteristic is not influenced by close family contact with C.C. Optimism-progressivism showed no correlation with either age or years since graduation, and essentially no correlation with knowledge- though a very slight relationship here ( r = 0.14) suggests that refinement and further testing of these dimensions may be revealing. For the present it is concluded that a positive, optimistic, progressive outlook towards C.C. is not related to knowledge, family experience, or age, and it is no more a characteristic of physicians than of surgeons or gastroenterology trainees. DISCUSSION Clearly, the level of knowledge of aspects of C.C. among this group of gastroenterological specialists is lower than might be expected or desired. Knowledge tended to be best developed in respect of tangible matters of immediate significance to direct patient care: advice that adenomatous polyps are premalignant and should be removed; that malignancy varies with the size of the polyp; and

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that the rest of the colon should be checked if a polyp is detected. On the other hand, knowledge tended t o be least developed o n m o r e epidemiological matters such as knowledge of the incidence of synchronous colonic polyps; the increased risk of metachronous C.C.; the proportion of C.C within reach of a digital rectal examination and the sigmoidoscope; the familial risk of C.C.; and the fact that C.C. is the commonest internal cancer in Australia and the U.S.A. Questions such as these are as important as the more practical questions concerning patient management. It is likely that the surprising ignorance of recent developments in C.C. uncovered by this study extends to other areas of C.C. knowledge, and to other groups of doctors. An even lower level of knowledge could be expected amongst other groups not regularly exposed to C.C. Delay in diagnosis of C.C. occurs in 20% to 50% of patients (Clarke and Jones, 1970; Pheilsetalii, 1976; Cohen and Davis, 1976; Peltokallio, 1965). Although over half the cases of delay are due to delay by the patient in seeking medical advice, medical delay may have more serious consequences, destroying the patient‘s confidence in his or her physician. Ignorance of recognized high-risk groups (such as patients with adenomatous polyps) may not only delay diagnosis, but result in failure to take simple measures to prevent colorectal cancer (for example, removal of a polyp). What is the reason for this lack of knowledge, and how mightitberectified?AreviewofthreeAustralian journals (Medical Journal of Australia, Australian and New Zealand Journal of Medicine, Australian and New Zealand Journal of Surgery) revealed only seven original articles and two editorials on C.C. over the past two years. There has been little input on C.C. at meetings of the Gastroenterolgoical Society of Australia in recent years. Although C.C. is the commonest internal malignancy in Australia, and is now a major problem facing the Australian community, there is a tendency for this topic to be displaced by more “exciting” topics at scientific meetings. There is obviously a need for more up-todate knowledge input and a reassessment of the methodology of continuing medical education.

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CONCLUSION A surprising unawareness of recent developments in C.C. was apparent in this group of 73 gastroenterological specialists, and suggests failure of our traditional methods of continuing education. Both knowledge and attitudes in all three categories were spotty and not coherent, Overall, both knowledge and attitudes on C.C. were not related to age and years since graduation of the respondent, and were not significantly different in the three groups tested. Knowledge and attitudes towards C.C. may be a factor in doctor delay in diagnosis and medical acceptance of population screening. Earlier diagnosis of C.C. either by screening or by improved public and medical education. must take into account current knowledge and attitudes of all groups involved.

REFERENCES BASSETT M. and GOULSTON, K. (1978), Med. J. Aust., in press. BERG, J.W. and HOWELL, M.A. (1974), Cancer (Philad.) 34: 807. BOND, J.H. and GILBERTSEN. V.A. (1977). Gastroenterology, 72: 1031. CLARKE, A.M. and JONES,I.S.C. (1970). N.Z.med. J., 71: 341. COHEN,J. and DAVIS,N. (1975), Med. J. Aust., 1: 437. DUNSTONE, G.H. and KNAGGs. T.W.L. (1972). J. med. Genet., 9: 451. HACKETT,T.P., CASSEM. N.H. and RAKER, J.W. (1973). New Engl. J. Med., 289: 14. HUGHES. E.S.R. (1976), Med. J. Aust., 2: 365. HUGHES, E.S.R. (1977), Sunday Telegraph, Sydney, July 10. LOVETT. E. (1976). Brit. J. Surg., 63: 13. R.H., LINDNER, A.E. and MAKLANSKY. D. (1976), J. MARSHAK, Amer. med. Ass., 235: 2856. MILLER,D.G. (1973), Publ. Hlth., (Lond.), 87: 67. MORSON. B. (1974). Proc. roy. SOC.Med., 67: 451. MORSON.B. (1977), Abstract, International Conference on Gastrointestinal Cancer, Tel Aviv. MUTO. T., BUSSEY.H.J.R. and MORSON.B.C. (1975). Cancer, (Philad.), 36: 2251. R. and MACLEAN. L.D. (1976), MZABl. R., HIMAL,H.S., DEMERS. Surg. Gynec. Obsret., 143: 959. CANCERREGISTRY (1972). NEWSOUTHWALESCENTRAL NUNNALLY. J.C. (1967). Psychometric Theory, McGraw Hill, N.Y.. ch. 8. PELTOKALLIO. P. (1965), Acta chir. scand., Suppl: 350. PHEILS, M.T., BARNETT.J.E., NEWLAND, R.C. and MACPHERSON, J.G. (1976), Med. J. Aust. Special Suppl. 1: 17. TYDEMAN. J., BASSETT, M. and GOULSTON, K. (1977), Proc. Clin. Oncol. SOC.Australia, 1: 164. WINAWER, S.J.. SHERLOCK, P., SCH~TTENFELD, D. and MILLER, D.G. (1976). Gastroenterology, 70: 783. WINAWER. S.J. (1976). Gastroenterology, 71: 1101. WINAWER.S.J., MILLER,D.G., DRESSLER, M.. SCHOTTENFELD. D., SHERLOCK, P.. EDEMAN.M.. HAJDU,S. and STEARNS. M. (1977). Digestion, 16: 285.

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Knowledge and attitudes of gastroenterologists in colorectal cancer.

COLORECTAL CANCER DENT ET ALli KNOWLEDGE AND ATTITUDES OF GASTROENTEROLOGISTS IN COLORECTAL CANCER OWENDENT',MARKBASSETT~ AND KERRY GOuLSTON3 Gastr...
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