SIXTH INTERNATIONAL COURSE ON THERAPEUTIC ENDOSCOPY

Endoscopic palliation of colorectal cancer

G NUSKO, C ELL

G NUSKO, CELL Endoscopic palliation of colorectal cancer. Can J Gastro­enterol 1993;7(6):466-470. Palliating colorectal cancer by endoscopy means palliating rectosigmoidal cancer. Surgical palliation is preferred in tumour stenosis located higher than the first th ird of the sigma or distal rectum with infiltration of the anal and pcrianal region. Indications for endoscopic palliation arc limi ted to incurable rectosigmoid tumours with multiple metastases, for genera l inoperability or in recurrent anastomotic cancers. There are several methods currently available for local palliative therapy. Cryotherapy is obsolete because of the acute and late bleed ing risks from the base of the tumour. Elcctrocoagualrion is feasible, however, time-consuming using the monopolar method. If the tumour is highly stenotic, auxiliary techniques consisting of prelaser bouginage or balloon dilat ion are useful. Combination therapies with intra luminal high dose irradiation or metal stents seem to be promising, accord­ing to a few case reports. At the present time, endoscopic laser therapy is the most established palliative treatment for colorecta l cancers. Standard is the solid state neodymium: Y AG laser. Contact laser therapy with sapphire tips or hare fibre has the advantage that no gas insufflation is required. T his makes the procedure more comfortable for the patient. On the ocher hand, these techniques are more time-consuming than the noncontact laser irradiation. Laser therapy can be performed as an out-patient procedure. The success rate of more than 90% can be achieved with a very low complication rate of about 5%.

Key Words: Colorectal cancer, Endoscopy, Palliative therapy, Recwsigmoidal cancer

Traitement palliatif endoscopique du cancer rectocolique

RESUME: Le tra itemenc palliatif endoscopique du cancer rectocolique suppose un tra itement palliatif du cancer rectosigmo'idien. La chirurgie palliative est preferee clans les cas de stenose tumorale localisee plus haut que le premier tiers du rectum distal, avec infiltration de la region anale et perianale. Les indications

Division nf Gastmi111estinll/ Endosrn/>y, De/>artment of Medicine, University Erlangen-Niimberi, ErlanJ?en, Gennany

Corres/xmdence: Pri~, Doz Dr C Ell, Division of GllStrnintestina! Endoscopy, De/>llrtmenr of Medicine, University Erlange11-Niimhe1·g, Krnnkenhausstr l 2. 85 20 Erlangen, Germany. Fax (0049) 9/3 1-26/9 /

CANCERS OF THE COLON AND REC­

tum are among the leading causes of morbidity and mortali ty in the West­ern world . In the United States, 150,000 cases were diagnosed in J 989 (500,000 cases worldwide), with an overall mortality of 50% ( l ). The inci­dence of colorectal cancer is increasing. The lifetime risk of developing colorec­tal cancer between the ages of 50 and 75 years in the United States is ap­proximately 5%, with a 2.5% chance of dying from it (1) . The median age of diagnosis is 71 years and the risk in­c reases with age (2). The standard treatment for cancer of the large bowel is surgical removal. Extended disease or recurrent disease is unlikely to he treat­able except by palliation . Patients with advanced colorectal cancer should a lso undergo pall iative resection whenever possible because resection decreases pelvic complications, ie, pelvic ab­scesses, sepsis and pelvic pain (3 ). The purpose of palliative treatment is to re­lieve symptoms, to prevent obstruction and to improve the patient's quality of life.

A nonsurgical palliative treatment is indicated if the genera l condition of the patient does not a llow surgery; in patients with nonresectable tumours, associated with high surgical mortality

466 CAN J GAsnOENTEROL VOL 7 No6 JULY/AUGUST 1993

J'une cmloscopie palliative se limitcnt aux tumeurs rcctosigmo'idiennes avec mecasrascs multiples, clans les cas gcnera lemcnr innpcrables ou dans Ics cas de cnncer anastomoses inopcrables. Diverses techniques sont offertes a l'heurc actuellc en traitemenc palliatif. La cryotherapie est dcpassee a cause des risques aigus et tar<lifs d'hcmorragie de la base de la tumeur. L'clcctmcoagulacion est faisable, mais cllc requien beaucoup de temps par la mcthode monopolairc. Si la tumeur est trcs stcnoscc, lcs techniques auxiliaires de bougirage par laser ou de Jilatacion par ballonnet sont utiles. Les craitements d'association avec irradiation transluminale a J ose e levee ou cxtcnseurs me ta lliques semhlenc etre des mcchodes promeueuses, scion quelqucs rapports de cas. Prcsentement, le traite­ment endoscopiquc au laser est le traitemenr palliatif le mieux etabli pour les cancers rectocoliqucs. La norme se base sur le laser Nd-YAG. Le traitement par contact laser avec pointes de saphir ou fibre nue a l'avantage qu'aucune insuft1a­t1on Je gaz n'est nccessaire. Cela rend !'intervention plus confortable pour le pat1enl. Par contre, ces techniques requiercnt plus de temps que !'irradiation au laser sans contact. Le traitcmcnt au laser peut s'cffectucr en extcrne. Le caux Jc rcussite peut ancinJre 90 % avec un caux de complication d'environ 5 %.

rate of between 25 and ,61\1; anJ in pan ems re( using cnloswmy ( 4). A fur­ther indication may be seen in stenos­mg nonrescctahlc recurrent cancer in the rectum. There arc different merh­lxls currently availnhlc for local, non­,urgical pall1acivc therapy.

ELECTROCOAGULATION Electrocoagulatinn has hccn in use

l'1>r severnl decades for curat ivc or pal­liative treatment. Endoscupically, a ,nare or loop elecrrode can be used to

carry out clectrod1sscctinn of the tu ­

mour. Using culling or blended cur­rent, the tumour is scraped away step hy ,tcp and the resu It mg de feet is coagu­lntcJ. The coagu l,ning current can he u,ed in cwo ways: ro fulgurate che tu­nmur when sparb arc created between the electrode and the tumour; or to boil the tumour, when the current b used at

:1 lower setting, the thermal damage b more limited and hcttcr visual control can be exeneJ. The technique must be re,en·cd for treatment of exophyttc tu ­

mour~ lying below rhc pcriwneal re­flection hecause of complicating perforatton. A general or regional anes­thesia b necessary. The comrlicmion rare in several recent stuJics varies he­rween 8 and 28%. The mam compl1ca­tt0t1.S reported arc hemorrhage, perforation, rectovaginal or rcctovesi­cal fbtula~. rectal strictures anJ pen­anal abscesses (5,6) with a mortality r,1tc of2.7%. Satisfac tory palliation was .1Ch1e,·cd 111 about 77 to 94°'0.

Cnntammation of the rip of the probe hy coagulation and cha rred ma­terial, and adherence co the tissue have hecn eliminaccJ by the clcctro-hyJro­chcrmo principle (El IT), which em­ploys water imt illation at the tip 11f the clccrmdc, simultaneously with the co­agulation. This method, already proven as a hcmostatic technique, is ;ilso su it­able for tissue Jcstruct1on by means of high frequency currents. lt was found that the depth of penetration inw the tissue at a given laser sctrmg could also he achieved wi1h modulated high fre­quency currcn t ( 7). For pall iall vc de­struction, high frequency current (coagulatton current) appears tll be ,ls

suiu1hlc as the far more expensive laser treatment. However, experience with monnpolar clcccrocoagulation revealed thm it takes ron much t imc to remove larger rumour masses in contrast to la­ser photocoagularion. Urological rctroscopc: The urological rcsectoscopc has been used for pall ia­Cl\' l' local treatment of rectal tumours. The advantages claimed by the users of chis technique (8) compared with con­,·cnrional clccrrocoagulation arc a bet­ter view of the operation field hy the continuous fluid irrigation and no need of anesthesia. The average operating time is 25 mins. In a series of J 5 patients there was good palliation of constipa­tion, bleeding and tcncsmus in J 2 pa­ticnrs ranging from three to six months. There were two postoperative compli­cations, one mtestinal perforation and

C\N J G·\~"fROENTFWI Veit 7 Nl) 6 jlll )/AUl1U~, 1993

Endoscopic palliation

an emholic stroke. No other complica­tions were rcpnncJ, such as sepsis, blecJing, incontinence, abscess or stric­ture (8).

CRYOTHERAPY Cryotherapy has been useJ only as a

palliative method for local treatment, in contrast to clectrocoagulation. A closed system with liquiJ nitrogen is employed. The temperature of the probe tip is about - l60°C to - 185°C. By measuring temperature, the hounJa­ries of complete tissue destruction 1s reached in a distance of 4 ro 8 mm (9). Cryotherapy is endoscopically easy to

apply ,md docs not require general an­esthesia. Although it causes little post­operative pain, a rectal discharge due to

sloughing of the necrotic tissue for a period of ahour two weeks is reported. The technical advantage of cryorhcr­apy C<lmparcd with clectrocoagulation is the absence of smoke obscuring the view during t rcatment. Cryotherapy is an out-patient treatment. A complica­tion rntc Llf IO to 42% has been re­ported ( I 0, 11 ). C1mplication~ include hemorrhage, perforation, fistula, and recrnl ~rricrurc,. The complication rate can be reduced hy treating only cxo­phytic tumour, lying below the pcrtto­neal reflection. Relief of symptoms is achieved in about 70 Ill 90'Yii of pa­tients.

SCLEROTHERAPY Polidocanol solutions have hcen

u~cd m the trcatmenr of esophageal and lower limb variccs hy interrupting the circulation in the venous vessels. lntra­tumornl inject ion of polidocanol was fi rst employed for the treatment of esophageal carcinoma ( 12). In a small ~erics of five inoperable pc1tients with advanced rectal tumour rembsion of the obstructive symptoms was ohserveJ after intratumoral injection of IO to 25 mL 3% poliJocanol. None of them re­quired colostomy. No complications occurred following sclcrothcrapy, but one pat ient experienced a hypertensive crisis. Sclerothcrapy can be performeJ safely as an mn-patient rroccdure in any endoscopic department with a very simple and inexpensive sec-up yielding satisfactory results ( 13 ) .

467

Nt "Kt ) \NP Eu

Figure 1) Afwrloliding bougie for endoluminal imidiarion

Figure 2) Laser ll'Chnique for endmrnfiically passable t1m1011r stenoses

A series of 31 patients was t reat ed hy endocavitary irradiation for palliatio n (Figure I). The resu Its of this study showed chat good local conmil of ru­mour growth was obtained in 68% of cases. Togethe r wi th externa l irradia­tio n, the usual dose rate is 900 en 1000 rad tumo ur dose per week for a large volume of tissue. Using the cndocavi­tary method, 3000 rad is delivered to a small nrea in 3 mins every ocher week. Using th is fractionauon , generall y moderately resistant adenocarc inomas become radiosensit ive. A t l cm depth the Jose ts 35%, and at 2 cm depth the dose is l 4%. There appears to he ve ry little morbidity fmm this type of rhe r­npy. Lesions siruared within the firs t few centimetres of the anal verge seem to have an increased risk of morhidiry. Minor supe rfic ia l necrosis has been ex­perienced hy 2 3% of patients, and hlecding about one year afte r treatmcn t due to tcleangiectasia by 7%. A ll pa­tients were treated on an Olll· patient hasis (14). A furthe r series of 64 pa­tients with extensive adenocarcinoma

468

Figure 3) Prelaser-lxn1,tienage for im{l<1.1sahle Ullll<ll!T StellOSt'.I

Figure 4) l 'se of che la.1er-resi,wnt guide /JTohe in highly stenocic twncmrs

nf the lo wer th ird of the rectum were treated hy external beam 60 cobalt irra­d iation fo llowed hy inrracavitary and 192 iridium implant after a two month inte rval. After th ree years the local tu­mour con trol rate was 79. 5% and sur­viva l was 83% (15, 16).

TRANSENDOSCOPIC BALLOON DILATION

T ransendoscopic ball non dilatton of partially obstructing tumours as an ad­juvant to laser phototherapy has heen reported . Even in comple te ohstruc tion successful balloon dilation and tempo­rary rccanalization of the bowel lumen in three patients allowed a washout of howel content and relief from d1 , ten­sion so tha t single stage operations or retrograde endoscopic lase r pa llia tion in a c leaned gut could he petfnrmed ( l 7). The balloon is centred within the lesllm and mflated for 3 mms by filling to the recommended distension pres­sure ,is indicated by a mano meter. Bal­loon d i lat ton is un li kely to he successful in pat ients with sharply angula ted or c irrhous lllmours. O bstruccing lesions

of the dista l and mid-third of the rec­tum can be treated a lso with conven-

tional bougies - as used for the upper gastrointestina l tract.

RECTOSlGMOID STENTS There arc a few case reports dealing

with proctoscopically placed reccos,g­moid stents in treating obstruc ting rcc­tosigmoid neoplasms in pat ients not suitable for surgery. This seems to be a new promising technique (1 8, 19), hut larger series h,we to prove success rates and complications. S imilar to the upper gastrointestina l tract stcr\ts, obstruc­tion by stoo l masses or recurren t tu­mour infiltrat ion has to he expected (20).

PHOTOOYNAMlC THERAPY Photodynamic therapy is based on

the systemic administ ra t io n of a photo­sensitizer which is prefercnually re­ta ined in malignant tissues. W hen the sensitized tissue is exposed to light , cy­totox ic compounds arc produced. Pho­todynamic the rapy has been shown to

he a safe method and can completely eradic;He some l,ma ll colorectnl cancers (21,22) . l lowever, the limitat ions in the depth nf light penetrnnon, even with high energy lase rs, wi ll most like ly limi t the usefulness of th is modality in advanced d isease (23,24).

Pat ients unsui tahlc for surgery with advanced cancers of the rectum and distal sigmoid colon tha t arc causmg sympto ms from the intra lumina l hulk of tumour a rc good candida tes for laser therapy. Using the neodymium (Nd): Y AG laser nt h igh power (50 to 90 W) wich the fibre held 5 to 10 mm ahove the target t issue, neoplastic a reas can he vapori:ed or just coagulated, and the necrozed a reas a llowed to slough (25). Coagula ting the tumour tissue seems to

be snfcr, but it requires more endo­scopies as less bulk can he destroyed during each treatment. If the tumour stenosb can be passed endoscopica lly, laser therapy should be started at the proximal margin of tumour (Figure 2). The irrad ia tion should be cont inued in a ci rcular 'pamt brush' fa hio n down w the distal tumour margin. lf the stenosis is very t ight and doc, not ;i llow the passage of an endoscope, prclaser d ila­tion or hougenage should be performed before laser therapy b started (Figure

CAN J GASTROENTER()I. Vo, 7 No 6 JUI Y/AUt.U'5f 1993

Endoscopic palliation

Figure 5) Highh 1r.enouc wmour ,tcmoses prior w (left) , during (centre) and aftcr (right) the fir.It laser session using cJ1c h1er-remumt gwlU' />rohe and /mer con wet rltcrn/>'1

3). An alternative tec hnique is the use of the laser-rcsistam guiJc probe as shown in Figures 4 and 5. Another ap­proach is the use of sapphirc-llppeJ fi­bres or bare fibres, which arc used in contact with the tissue at a much lower laser power setting ( 10 co 15 W) (26). They have the advantage of not requir­ing coax ial ga, to cool the tip, which may make the procedure mmc comfort­able; however, repeated endoscopy is necessary. In a randomized study, Nd:Y AG laser therapy by the en­doscopic contact low power method was compared with the noncomact high power method for palliation 111

colorectal cancers (27). Contact laser therapy was tolerated better by the pa­ttrnts and was espec ially suitable for binns that arc difficult to treat from a distance. No smoke general ion and no risk of damage to endoscopes are other aJ\'antages. The disadvantages of con­tact laser treatment arc the lack of vis­ual rnntrol over therapy, possible dam­age rn healthy tissue, adhesion, a higher cost and length of procedure. Compar­ing therapeutic effectiveness 111 a ran­domized study of a coaxial fibre versus a ~are fibre for endoscopic Nd:Y AG laser therapy of rectal tumours revealed no

REFERENCES l. Wmawer S, St John J, Bond J , Ct al.

xrecning of avcrage-rbk ind1v1Jual, for colorcc1al cancer. Bull WI 10 I 990;68:505-13.

2. Levin K, Do:,H~ R. Ep1dem1ology anJ large bowel cancer. WorlJ J Surg 1991;15:562-7.

,. Longo WE, Ballantyne GI I, Bilchik

significant differences (28). Another technique that has been promising in experimental studies i~ interstitial hy­pcrthermia. In Lhis approach the tip of a bare laser fibre is directly inserted into the target tissue using the laser at even lower power ( l co 2 W) to get precise local coagulation (29).

The immediate succe~ rate of laser therapy in pallimion for advanced rec­tosigmoid cancers was up to 90% in patients with distressing symptoms from intraluminal tumour bulk affected hy the circumferential extension (30). Pattents with smaller wmours were more likely to experience relief from symptoms than patiems with large Cll ­

mours (31). The benefits from laser treatment appears to more for patients wnh bleeding (90 to 100% ) than with obstruction (70 co 80%) (3,7,JJ). The duration of response is limited. Some authors carry out regular fo llow-up sig­moidoscopy at four to LO week intervals wirh further laser therapy as necessary. Other investigators suggest to wait fo r sympto ms to recur. In these studies, an average treatment in terval of ahout 4. 5 months has been recorded (27,32).

Complications caused by laser treat-

AJ, Modlin IM. Advanced rectal cancer. What is the beM palliatkm? Dis Colon Rectum 1988;3 1:842-7.

4. Ho henberger W, Altcndorf A, H.ermanek P J r, Gall FP. The laser in gastroenterolo1,,,y: Malignant lllmours in the lower ga,trointcstinal tract -therapeutic alternative,. Endoscopy 1986; 18:47-52. (Suppl)

C\Nj GASTROENTEROI Vm 7 No 6 JL I.Y/AIJOU~T 1993

mem, such as hlcedmg, fi stulas, perfo­ration and abscesses, were reported m 4 to 19\l{i of patients (33-35 ). The overall mortality for purely palliative surgical procedures can he as high ;is 21 % ( 36). Laser-related mortality due to perfora­tion has been reported as 2.3% (37). In one study, quality of life was evaluated prospectively during, and at tntervab after, laser therapy (38). Overall there was a significant improvement from the mean pretreatment score :mJ rhc best score achieved after therapy. PaLients with Jiarrhea, rec tal bleedmg, mucus discharge or pam secondary to tumour hulk will benefit mosl from laser treat ­ment. Pauent 111 whom mal1gnam cachcxia, pain secondary to :-.acral plexus involvement and sphincter dysfunction are predominant over local effects of t he disease do not benefit greatly, and quality of life scores deteriorate. In a study comparing costs and complica­tions of endoscopic la er therapy versus palliative surgery ( 39), the authors con­clude that the cost of endoscopic laser therapy is significantly less, anJ that hospital ization, intensive care treat­ment and complications are s ignifi­cantly higher in patients undergoing palliative surgery for colorectal cancer.

5. I loekstra I IJ, Verschueren RCJ, O ldhoff J , Plocg van dcr E. Palliative and curntive electrocoagulatton for rectal cancer. Experience and results. Cancer 1985;55:210-3.

6. Salvati EP, Rubin RJ, Ei>cmtar TE, Siemens GO, Mangione JS. Electmcoagulatinn of ~elected

469

NUSK~) /\NP Eu

carcinoma of the rectum. Surg Gyn Methodc,endoskopi,che lmplanration 29. Matthewson K, Barton T, Lewin MR, Obset 1988;166:393-6. einer Rectum-Prothese zur Palliation O'Sullivan JP, Northfield TC, Bown

7. Mmck W, Rl!idenbach HD, Wittmann beirn Rcctum-Karzinom. Z SG. Low power interstitia l NJ, YAG A, Beierlein L, l lermanek r. A Gastroenterol 1991 ;29:447. laser phutocoagulation in normal and comparative study of' the tissue- 19. Keen RR, O rsay CP. Rectosigmoid neoplastic rm colon. Gut J e,troying effect oft he laser and Stent for obstructing colonic 1988;29:2 7 -34. clcctrocoagulmion. Endoscopy neoplasms. Dis Colon Rectum 10. Brunctaud JM, Maunoury V. L 989;2 I: 31-6. 1992;35:912-3. Cochclard D, Cortot A, Paris JC.

8. Kurz KR, Pitts WR, Speer D, Vaughan 20. Ell C, Hochherger J, Fleig WE, May A, Lasers in recrosigmoid rumours. Lasers ED. Palliation ,if ca rcinoma of the Dertinger S, Hahn EG. Self expanding Mcd Sci l 990;5:224-32. rectum and pararectum using the metal stem s for the upper G I-tract. H. Bright N, Hale P, Mason R. Poor urologic re,ectoscope. Surg Gyn (In press) palliation of colorectal malignancy Ohstel 1988; 166:60-2. 2 l. Barr H, Bown SG, Krasner N, Boulos with the neodymium yttri um-

9. Knoch HG. I 5-Jahre-Erfahrungen mil PB. Phomdynamic therapy for aluminium-garner la,er. Br J Surg der kryoch irurgischen Behandlung des colorcctal disease. Int Colorect Dis 1992; 79:308. Rektumkarzinnm:,. Zbl Chirurgie 1989;4:15-9. 32. Brunetaud JM, Maunoury V, 1985;110: 155-8. 22. Gossner L, W ittke 11, Wmzecha A. Cochclard D, Conm A, Paris, JC.

10. Schumpdick V, Truong S, Verapami l and hemaloporphyrin La,cr pallimion for rectosigml>id Kupc:yk ,Joeri, D. Stellenwen der derivative for tumour destruction by cancers. lnt J Colorecl Dis 1989;4:6-8. Kryo-, Elekw,- und La,er-Therapic phorndynamic therapy. Br J Cancer 3'3. Brunetaud JM, Maunoury V, Ducrotrc heim Reclumcarcinnm. Chirurg l 99 1 ;64:84-6. P, Cochclard D, Cortot A, P:1ris JC. 1988;59:6 39-46. 23. Barr l 1, Boulos PB, Chadani C, Palliative treatment of rectosigmoid

I I. T heiss R., Schmid t Kl I, Ruess G, &iwn SG. Photodynmnic carcinoma by lm,er endo,copic Jungmgcr Tl I. Kryotherapic beim therapy for colorecta l c.incer: phntoablation. Gastnicntcrolngy inopernblen Rekrumkarzin,lm. Zhl A quantitat ive pilot study. Br J Surg t 987;92:663-8. Chirrurgie 1985;1 L0:142-6. 1990; 77:93-6. 34. Mathus-Vliegen EM! I, Tytgat GNJ.

12. Soehendra N, Grimm I I, Schreiber 24. Kashrnn H , Papa MZ, Wilson BC, Nd, Y AG laser phntocoagula1 ion in I lW. Endoskopische lnjektions- Delllch AA, Stem I IS. Use of gastroentenilogy: I rs role in palliation hchandlun~ hci henigncn und photodynamic therapy in rhe uf colorecu, I rnncer. Lasers MeJ Sci malignen Osophagussrenosen. Deutsch palliation of massive advanced rectal t 986;1 :75-80. MeJ Wschr 1984;109: 1973. cancer. Dis Colon Rectum 35. Mathu,-Vl iegen EMH, Tytgat GNJ.

I 3. Marini E, Frigo F, Cavar:ere L, C uwlo 199 t ; 34:600-5. Analyses of foi lures and complications S, Palazzin L, Orcall i F. Palliative 25. Fleischer D. P<1llimive therapy of of neodyni um:YAG laser photo-tre1111m:nt of carcinLmla of the rectum malignant tumours. In: Riemann JF, coagulation in gastro intest inal tract by endoscopic inJcction llf Ell C, eds. Lasers in Gnstroenterology. tumours. Endo,copy 1990;22: 17-23. pti lidocanol. Emh,c,lpy 1990;22: 171 -3. International Experiences and Trends. 36. Gol igher J. Surgery of the Amis,

14. Si>chy B, Remi ngton JI I, S,)bel SH. Stuttgart: G T h ieme, 1989. R.ecrnm anJ Colon. Lnndon: Balliere Treatment of recrnl carcinom,1s by 26. Ell C, Hochberger J, Lux G. Tindall , 1984. means of endocavirnry irrndiarinn: Non-contact versus contact Nd: Y AG 37. Cutsem v;in E, Boonen E, Cchocs K, A progre~, reporl. Cancer laser therapy for ~tcnoscs in the ct al. Risk factor~ which determine the 1980;46: l 957-61. gastroinre~tinal tract. Lasers Med Sci long term outcome of neodymi um-

15. Papillon J. New pro,pecl, in the 1986;1:283. YAG laser pall i:1tion of colorecral conservative trealmelll of rectal 27. Rmgeens P, Vantrappen G, carcinoma. Int J Colon Db cancer. Dis Colon Recwm D'Heyegerc F, Geboes K. Endoscopic 1989;4:9, I I. l 984;27:695-700. contnct Nd-Y AG laser therapy for 38. McGowan I, Barr 11, Krasner N.

16. Papillnn J. Radimiun t hernpy colorectal cancer: A randomized Pall iative laser therapy for inoperable 111 the con,ervative mnnagemenr comparison with non-contact therapy. rectnl cancer - does it work 1 A of c,mcen, o( the l(>W rectum Lasers Med Sci l 987;2:69, 72. prospective study of quality of life. and anal canal. Int J C<ilon D1, 28. Naveau S, Poynard T, Zourabichvili Cancer 1989;63:967-9. 1986; I :251 -5. 0, Poitrine A, Chaput , JC. A 39. Mellow Ml l. Endoscopic la,er

17. Stone J M, Bloom RJ. Tr:mscndnscupic randomized study of conxial fiber thernpy as an alternative to palliative hallonn dila tation of complete colonic versus a naked fiher for endoscopic surgery for adenocarcinoma of rhc llhMrucrinn. Db Collln Rect Nd:YAG laser therapy of esophageal rectum - comp,irison of costs and 1989;32:429- 31. and rectal tumours. GastrointcHinal complication,. Gastro inte>l EnJnsc

18. Dohnww M. Ru pp KD. Neuc Endrn,c 1989;35:201,6. I 989; 35:283-7.

470 CAN J GASTROENTEROL VOi 7 No6JULY/Aut,UST 1993

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