53 ISSN East Cent. Afr. J. surg

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1 53 Aement of DRE and PSA a Diagnotic and Screening Tool for Carcinoma of the Protate in Rural Nigeria. E. Irekpita, C. Owobu, E. Aigbe 3, G. Obaikene 3, A. Igbe 2. Dept of Surgery, Ambroe Alli Univerity, Ekpoma, Nigeria. 2 Dept of Hitopathology, Irrua Teaching Hopital, Irrua, Nigeria. 3 Dept of Surgery, Irrua Teaching Hopital, Irrua, Nigeria. Correpondence to: Irekpita Ehiobo, iehiobo@yahoo.com Background: Carcinoma of the Protate i a major health burden globally. Thi tudy wa aimed at aeing the value of digital rectal examination and protate pecific antigen a creening and diagnotic tool for carcinoma of the protate in rural Nigeria Method: Men who had abnormal digital rectal examination (DRE) finding, elevated protate pecific antigen (PSA) and protatic hitology within the period were included in the tudy. Data related to age, PSA value, DRE finding and hitology were analyzed uing SPSS and imple tatitical method. Reult: The total number of patient wa one hundred and fifty eight. The peak decade of occurrence of protate cancer wa the 6-7 year. When DRE finding wa cro tabulated with hitology, there wa a ignificant correlation (P=.). The poitive predictive value (PPV) of DRE wa 96.5% while the negative predictive value (NPV) wa 93.5%. For PSA, there wa alo a ignificant correlation (P=.). The PPV of PSA wa 64.9% while the NPV wa 96.33%. Concluion: The extremely impreive performance of DRE and PSA a diagnotic and creening tool may be due to the limitation of the tudy to a cohort of patient who already hard lower urinary tract ymptom. There i need for community baed tudie. Keyword: Screening, DRE, PSA, Poitive predictive value, Negative predictive value, Protate cancer. Introduction Carcinoma of the Protate Continue to be a major health burden worldwide. According to Jaon et al 2, the life time prevalence of the dieae i 7 percent. In the United State of American, 28, 89 diagnoi of the carcinoma of the protate were expected in 27 with correponding death of 27,5. In mot third world countrie, uch information are either canty or nonexitent. In Nigeria, available information are from the Urban center and are motly on incidence of the dieae; Port-Harcourt 3 4/,, Lago 4 27/,. The diagnoi of Carcinoma of the protate when affected men preent for evaluation, i baed on hitory, phyical examination and Invetigation. In imple uncomplicated dieae, the hitory i imilar to that of benign protatic hyperplaia (BPH), coniting eentially of Lower Urinary Tract Symptom (LUTS) 5. In advanced dieae when there are metatae, additional ymptom preent depend on the involved ytem. The hallmark of phyical examination in carcinoma of the protate i the digital rectal examination (DRE). Feature on DRE which point to the preence of carcinoma of the protate include enlarged protate, lobar aymmetry, nodularity, upiciou nodule and a rubbery or hard protate 6. Argen et al 7 in a ytematic review concluded that DRE i the oldet leat invaive creening tool for Ca protate with a high pecificity and a high negative predictive value though it moderate enitivity doe not allow for concluion. An abnormal DRE finding i an indication for biopy of the protate. Protate pecific antigen (PSA), a protein ereae produced only by the protate, replaced acid phophatae in 986 a an invetigating modality and ha ince become a reliable tumor marker and creening tool for carcinoma of the protate 8. PSA i not pecific for carcinoma of the protate a other dieae of the protate uch a BPH and protatiti may lead to an elevated COSECSA/ASEA Publication -Eat & Central African Journal of Surgery. Nov/Dec 24 Vol. 9 (3)

2 54 value. PSA i alo conidered a tumor marker that i not enitive enough a it i normal in ome patient with protate cancer. 9 The univerally accepted normal upper limit i 4ng/ml but it i alo well know that at thi upper limit of normal, ome cancer are mied. Eentially, biopy of the protate i advied when the PSA value exceed thi upper limit. In order to improve the enitivity of PSA, concept uch a age cut off, PSA velocity, free PSA and complex PSA were developed. PSA i preently the mot reliable tumor marker in carcinoma of the protate with a higher predictive value than DRE and TRUS. 9 Available data indicate that the PSA level i a, or more effective than DRE for the detection of protate carcinoma. Currently, for creening purpoe, a combination of DRE and PSA i recommended a thi approach yield up to 75% diagnotic enitivity for protate carcinoma though, in the American Cancer Society updated creening guideline for protate cancer, DRE i optional. Thi tudy wa done in Irrua Teaching Hopital, a Nigeria tertiary intitution baed in a emi urban etting and ub erving a population of 4 million people. To the bet of our knowledge, the role of DRE and PSA in creening for protate cancer ha not been tudied or documented in the rural Nigeria men. We therefore aim to add to available information on Ca protate with particular reference to rural black Nigerian men. Thi tudy will ae the value of DRE and PSA a diagnotic and creening tool for Ca protate in thi group. Patient and Method All men who preented at the Urology out patient, General outpatient and the Accident and Emergency unit of the hopital with LUTS BPH were included. However patient who were on treatment or have had treatment for protatic dieae before preentation at our hopital were exclude. Other excluded were LUTS due to Bladder dieae and Urethral tricture. All thee men were aeed with DRE and PSA and thoe who ' PSA exceeded 4ng/ml or had abnormal DRE finding were ubjected to protate biopy. Digital rectal examination (DRE) wa done in the left lateral poition. In very ick patient, the upine poition wa ued while the knee-elbow poition wa preferred in men who preented with urinary retention though the DRE wa repeated after the retention had been relieved. Factor uch a obliteration of the median groove, preence of upicion nodule, lobar aymmetry, generalized nodularity, tenderne and palpability of the eminal veicle were aeed for.all the DRE were done by pecialit Urologit. The pecimen for PSA meaurement wa obtained either before or at leat fourty eight hour after the DRE. The pecimen were centrifuged at three thouand revolution per minute. The upernatant wa tored at -2 O C-8 O C if the invetigation wa not done immediately. The DRG international Inc., USA enzyme-linked immunoorbent aay wa generally ued by thi Center during the tudy period. The finding on DRE, PSA value, the hitology report and patient age were recorded. The data o obtained wa analyzed uing the tatitical programming for ocial cience (SPSS-7) and imple tatitical method. Pearon chi quare wa ued to compare age, DRE, PSA and hitology. Reult A total of One hundred and Fifty -Eight patient een within the tudy period with complete data uitable for thi tudy were included. The age ditribution i hown in Table. Of thee, 95 (6.%) had CAP, 5 (3.2 %) had protate intra-epithelial neoplaia and 58 (36.75%) had BPH on hitological evaluation. The peak age at diagnoi of both BPH and CAP wa the eventh decade of life amounting to 35.4% of the total. The minimum age at which the diagnoe of CAP and BPH were made wa within the 5th decade of life (.9%). COSECSA/ASEA Publication -Eat & Central African Journal of Surgery. Nov/Dec 24 Vol. 9 (3)

3 Table. Age ditribution of Patient 55 Age Range Frequency Percentage Above Of the 58 patient, 62 (39.2%) had a benign feel of the protate on DRE, 24 (5.2%) had an obliterated median groove, 3 (8.2%) had a upiciou nodule, 53 (33.5%) had a hard and nodular protate and 6 (3.8%) had aymmetrical lobe giving a total malignant feel of the protate of 96 (6.8%). When DRE wa cro examined againt hitology, a ignificant correlation wa found (P =.). Eighty (84.2%) of the ninety ix patient who had a malignant protate on DRE had a hitologically confirmed CAP, while 43 (68.25%) of thee who had a benign finding on DRE were confirmed to have BPH. When age wa cro tabulated with hitology, there wa no ignificant correlation (P=.43). The poitive predictive value (PPV) of DRE wa 96.5% while the negative predictive value (NPV) wa 93.5%. Table 2 how the PSA ditribution ide by ide the finding when PSA i cro-tabulated with hitology. All the patient who ' PSA were above ng/ml were hitologically confirmed a having CAP. Below thi PSA value, a variable number of patient had hitologically confirmed CAP. Intereting i that between value of - 4nglml, two of the even patient had hitologically confirmed CaP. Chi quare tet howed a ignificant correlation between PSA and hitology (P=.). When PSA wa cro teted with Gleaon core, there wa no tatitically ignificant relationhip (P=.6).Figure iii how the relationhip between PSA and hitology. PSA had PPV of 64.9% while the NPV wa 96.33%. Table 2. PSA Hitology cro tabulation PSA Above Total Hitology BPH PIN CAP Total Of the Ninety One Patient who had hitologically confirmed CAP, and who ' Gleaon core were recorded, 7 (8.68%) had well differentiated tumor, 33 (36.26%) had moderately well differentiated tumor while the remaining 4 (4.6) had poorly differentiated tumor. When Gleaon core wa teted againt hitology, there wa a tatitically ignificant correlation (P=.). Between Gleaon core and PSA, there wa tatitically ignificant relationhip (P= COSECSA/ASEA Publication -Eat & Central African Journal of Surgery. Nov/Dec 24 Vol. 9 (3)

4 56.2). Thi wa different for age and hitology (P=.43). Dicuion Protate cancer i the leading non cutaneou cancer in the United State of America with a dieae related death reaching 29,72 in 23. The highet protate cancer incidence and mortality rate are reported in black African American men (AAM) living in the United State. 2 Thi i exceeded only by Jamaica with an incidence of 34/, 3. Data available alo indicate that the peak age for protate cancer i a decade earlier in black African American men in the United State. In thi tudy, the peak decade wa 6-7 year group. Little i known of the dieae in Sub Saharan Africa, the pooret Countrie of the world 4 and the origin of the black African American men. Available data are motly from GLOBOCAN and are often unreliable becaue they are derived motly from regitrie covering hopital, mall ub national area or only major citie. 5 Apart from the paucity of data in thi region, late preentation in the advanced tage of the dieae implie that the mortality rate may be higher than in the AAM currently. 6 The introduction of creening program in the developed world revolutionized the management of protate cancer. Thi wa aimed at early diagnoi at a tage the dieae i curable. 7 Currently, in thee fortunate area, concern now center on iue of over diagnoi and over treatment. 8 Such creening program are preently either erratic or unavailable in center like where thi tudy wa done and in hot, mot of Sub Saharan Africa. Several reaon uch a lack of awarene, ethical implication of diagnoi and lack of reource have been documented a reponible for thi 9. Thee factor are remarkably at play in thi centre with ignificant influence on the outcome of thi tudy. The two mot commonly ued variable for creening for protate cancer are digital rectal examination (DRE) and protate pecific antigen (PSA). DRE i the oldet and leat invaive method though a few patient are avere to it. DRE finding are conidered a abnormal when the protate i enlarged, the median groove i obliterated, the lobe are aymmetrical, there are (i) upiciou nodule, the eminal veicle are palpable or the protate i hard and or nodular. 2 The poitive predictive value (PPV) and the negative predictive (NPV) value of DRE of 96.5% and 93.5% in thi tudy, eemingly quite high, are explained by the extremely late preentation 2 by thi rural dweller. Factor uch a poor health care regulation, the claim by complementary and alternative medicine (CAM) practitioner in the tate media of their ability to cure everal dieae, poverty and ignorance account for thi late preentation 22. In thi late tage of preentation, even the Urology regitrar i able to predict protate cancer baed on DRE alone. Protate pecific antigen (PSA) wa introduced into clinical practice in the 986 for the purpoe of protate cancer creening. 23 Since then, the percentage of patient who preent with late dieae ha reduced remarkably in developed communitie 24. Percentage free PSA i mot ueful and helpful in deciding on biopy though in our centre, thi deciion i uually baed on total PSA, the upper limit being 4ng/ml. Thi upper limit ha been conidered imperfect a according to Thomon et al 25 at thi upper limit, ignificant number of cancer at lower PSA are mied. In our tudy, of the even patient with PSA of 4ng/ml and below, who had protate biopy done baed on DRE finding, two (28.57%) were poitive for protate cancer indicating that thi upper limit may be too high for thi community. However, local factor uch a the ource of the kit, torage facilitie and efficiency of the laboratorie may affect the PSA value 6. Studie have hown higher PSA value in AAM than CAM 26. However, ome tudie have pointed to factor uch a large tumor burden, preence of undetected metatai rather than more aggreive tumor biology, a a caue. Ikwuerowo et al 3 in their tudy indicated that the COSECSA/ASEA Publication -Eat & Central African Journal of Surgery. Nov/Dec 24 Vol. 9 (3)

5 57 common aociation of protatiti may be reponible for the higher PSA in our environment. The overall poitive predictive value of PSA above the cutoff of 4ng/ml fall within the often documented. In the work of everal author 27,28,29 above the cutoff of 4ng/ml, the PPV wa 3% while at the cutoff of greater than ng/ml, PPV wa 42-6%. The protate cancer prevention trial which biopied men with normal PSA level etimated NPV of 85% for PSA value < 4ng/ml, a figure fairly lower than the 96.3% obtained in thi tudy. Thi i till explainable by the late patient preentation with higher PSA value. For intance, patient who preented with PSA value of >ng/ml were all poitive for protate cancer on biopy. Thi may mean that in our low reource environment, uch patient could be pared protate biopy and diagnoi baed on PSA if other feature are preent. Thi tudy wa hopital baed, aeing the value of DRE and PSA a tool for creening for protate cancer in patient who already have lower urinary tract ymptom. Thi to a large extent, may have influenced their remarkable performance a creening tool a mot of the patent preented in the advanced tage. There i a need for community baed tudie in thee rural area to ae thee variable and etablih community baed predictive value in preparation for properly regulated creening program in ub Saharan African countrie. Thi will help to avoid unneceary protate biopie Reference. Reckler F. Protate Specific antigen in the diagnoi of organ confined treatable protate cancer. Sch Weiz Med Wochen ch 996; 26 (44): Jaon Wilbar, Roy J, Lucille A. Protate cancer creening: the continuing controvery. Am Fam Phyician 28; 78(2): Stephen Odunayo Ikuerowo, Olufumilade Akinfolarin Omianjo, Muftao Jimoh Bioku, Micheal Olawale Ajala, Victor Patrick Nonylim Mordi, Juliu Oluanmi Ehio. Prevalence and characteritic of protate cancer among participant of a community baed creening in Nigeria Uing erum protate pecific antigen and digital rectal examination. The Pan African Medical Journal 23; 5: Eke N, Sapira MK. Protate Cancer in Por t-harcourt, Nigeria: feature and outcome. Nig J Surg Re. 22; 4: Ezenwa E, Tijani K. Jeje A, Ogunjimi, Ojewola R. Prevalence of protate cancer among Nigerian with intermediate Total Protate pecific Antigen level (-4nglml): Experience at Lago Univerity Teaching Hopital. The internet Journal of Urology 22; 9:3 6. Arjen Hoogendam, Frank Buntinza, Henrica CW Velb. The diagnotic value of digital rectal examination in primary care creening for protate cancer: A meta-analyi. Family Practice 999; 6: Mohammed El Imam Ahmed, Nawal Zarong Higazi, Daffalla O Abdulidri, Ali Ahmed Idri, khaled El Tahir khaled, Mutapha Omran, et al. Protate pecific antigen veru digital rectal examination a creening for ca protate in Sudanee patient. Sudanee Journal of Public Health 29:4(2): Catalona WJ, Richie JP, Ahmann FR et al. Comparion of digital rectal examination and erum protate pecific antigen in the early detection of protate cancer: reult of a multicenter clinical trial of 6,63 men. J Urol 994;5: Micheal R Cupp, Joeph E Deterling. Protate pecific antigen, digital rectal examination and tran rectal ultraonography. Their role in diagnoing early protate cancer. Mayo Clinic Proceeding 993; 68(3): Manyahi JP, Muau P, Mteta AK. Diagnotic value of digital rectal examination, protate pecific antigen and tran rectal ultraound in men with protatim. Eat African Medical journal 29;86(9):. Siegel R, Naihadham D, Jemal A. Cancer Statitic 23 CA Cancer J Clin 23; 63(): -3 COSECSA/ASEA Publication -Eat & Central African Journal of Surgery. Nov/Dec 24 Vol. 9 (3)

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