A new combined approach in the conservative management of rectal cancer

Inl. J. Radiation Oncology Biol. Phys.. Vol. Printed in the U.S.A. All rights resrved.

17, p. 539-M Copyright

0360-3016/89 $3.00 + .oO 0 1989 Pe~mon Pm plc

??Original Contribution

A NEW COMBINED APPROACH IN THE CONSERVATIVE MANAGEMENT OF RECI-AL CANCER Y. OTMEZGUINE,

M.D.,* L. GRIMARD, M.D.,* E. CALITCHI, M.D.,* J. DESPRETZ, M.D.,? J. J. MAZERON,

M.D.,*

J. P. LE BOURGEOIS, M.D.,*

B. PIERQUIN, M.D.*

AND M. JULIEN, M.D.?

CHU HenriMondor,Crkteil,France Between 1980 and 1987, 25 patients with rectal cancer were treated with a combination of preoperative external irradiation of 35 Gy in 15 fractions over 3 weeks which was followed, 6 to 8 weeks later, by a tumorectomy and peroperatlve placement of a plastic tube loop for post-operative interstitial therapy by iridium-192. This boost dose was 20 Gy (Paris System) for submucosal lesions (seven patients) and 25 Gy for intramural (eight patients) and extramural (ten patients) lesions. With a mean follow-up of 40.5 months, there have been five local recurrences, the latest occur@ 16 months post-tumorectomy. Two of these five patients are alive and disease-free 1 year post salvage abdominoperineal resection. The 20 patients with local control have preserved a full functional sphincter and 19 of them are disease-free; there were few complications. This sphincter preserving combined approach seems promising- for patients with tumors of the middle and lower rectum who cannot undergo major surgery and for _ selected patients who refuse abdominoperlneal resection. Local excisions,

Radiotherapy,

Rectal cancer.

INTRODUCTION

preservation (21, 28). In 1980, we developed a protocol combining irradiation and limited resection to expand conservative management with curative intent in invasive adenocarcinoma of the rectum. This is a report on a limited number of patients with special emphasis on the radiotherapy techniques used.

The management of carcinoma of the middle third and lower rectum usually implies a radical resection with en bloc removal of the tumor, a margin of healthy tissue, and the regional lymph nodes (5, 35). Low anterior resection (LAR) with stapler has extended sphincter preservation in recent years without compromising cure or local control in comparison with the abdominoperineal operation (APR), (2,4, 30, 33,40). Nonetheless, 40-60% of resectable tumors of the lower rectum are usually treated by this latter procedure. For some patients, a permanent colostomy is psychologically unacceptable. Many patients do not benefit from these radical procedures (3, 22), which carry a significant morbidity with a mortality rate reaching 16% in patients over 80 years of age ( 16). In this context, local excision has been used more frequently over recent years, but its indications are controversial and this is considered to be a curative intervention in only 5% of patients at presentation (14, 17, 24, 39). Adjuvant irradiation has been advocated to reduce the incidence of pelvic recurrences (11, 12, 15, 26, 34, 37) and to increase resectability (6, 8). More recently, it has been used to alter surgical procedures, allowing sphincter

Between 1980 and 1987, 25 patients (10 men, 15 women) were treated by this combined approach. Their age ranged from 43 to 84, with a median of 74. All patients had a histologically proven invasive adenocarcinoma of the rectum and were treated with curative intent. Patients were included in this protocol for the following reasons: standard radical excision was denied because of high surgical risk ( 14 patients, ten requiring an APR, median age 79), and permanent colostomy was refused by patient (eleven patients, median age 62). Pretreatment evaluation included a routine examination, a chest X-ray, an ultrasound of the liver, an IVP, a barium enema, and a colonoscopy with a biopsy of the tumor. All patients had a rectal examination under neu-

* Department of Radiation Oncology. t Department of Surgery. Reprint requests to: Dr. Y. Otmezguine, dtpartement de car-

cinologie, CHU Henri Mondor, 5 1 ave du mar&ha1 De Lattre de Tassigny, 940 10 Criteil, France. Accepted for publication 15 March 1989.

METHODS

539

AND

MATERIALS

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Table 1. Pathological features at presentation:

September 1989, Volume 17, Number 3

25 patients Patients

Site: Lower rectum (2 to 5 cm) Middle third (6 to 10 cm) Upper rectum (11 to 15 cm)

16 8 1

Location: Anterior or antero-lateral Lateral Post. or postero-lateral

9 6 10

Size (maximum 1.5 cm 2.-2.5 cm 3.-3.5 cm 4.-4.5 cm 5.0 cm 6.-6.5 cm

1 2 7 11 2 2

diameter before irradiation):

Grade of malignancy Well differentiated Moderately differentiated Poorly differentiated Colloid adenocarcinoma

11 7 6 1

roleptic or regional anesthesia to assess tumor extension, mobility, and the presence of pet-ire&al nodes.

Tumors were located in the lower rectum in 16 cases (64%), in the middle third in eight cases (32%), and in one case, 12 cm from the anal verge. Tumor diameters ranged from 1.5 to 6.5 cm with a median of 4 cm. Only three (12%) patients had tumors with a diameter of less than 3 cm. Eleven tumors were well differentiated (grade l), seven were moderately differentiated (grade 2), six were poorly differentiated (grade 3) adenocarcinomas, and one was a colloid adenocarcinoma. The tumors were all mobile and digital examination did not reveal any perirectal nodes. The pathological features at presentation are summarized in Table 1. The minimum follow-up was 12 months and the maximum follow-up was 94 months, with a mean of 40.5 months. External irradiation The first part of the treatment consisted of preoperative external irradiation. The patients received 35 Gy in 15 fractions over a period of 3 weeks to the rectum and the perirectal lymphatics. Patients were treated in a supine position with 25 MV photons from a linear accelerator using the 4-field box technique, each field treated daily. The dose per fraction was 2.33 Gy, 60% contribution from the AP:PA portals and 40% contribution from the lateral portals. A typical AP:PA simulation film is shown in Figure 1. The upper margin is 1.5 cm below the sacral promontory, the inferior margin is at the anal verge for tumors of the lower rectum and above the anal verge for higher lesions, and the lateral margins are on the outer * Ethicon Inc, Somerville, New Jersey.

Fig. I. Simulation AP:PA film of a typical portal used for preoperative irradiation: 35 Gy in 15 fractions.

edge of the obturator foramina. Typical field sizes were 12 X 14 cm ARPA and 9 X 14 cm for lateral fields at mid-plane. All patients received the full course of preoperative irradiation. Tumorectomy Six to 8 weeks later, the patients underwent a limited resection under spinal anesthesia. The techniques used were the transanal (lo), or the perineal anterior transphincteric approach (38). The goals of the local excision were to achieve a complete resection of the tumor with 1 cm margin of healthy tissue, to leave, if possible, part of the muscular layer in the bed of the tumorectomy, and to allow the radiotherapist to place a plastic tube loop around the surgical incision for postoperative curietherapy. In the transanal approach ( lo), used in 22 patients, the patient was placed in the lithotomy position and the anal canal was dilated. Once the tumor was visualized, the surgeon surrounded it by multiple l/O silk traction sutures and gently pulled the tumor down. The tumorectomy was then performed with curved scissors and hemostasis was achieved by electric cautery. The wound was sutured gitudinally with 3/O Vicryl.*

lon-

Rectal cancer 0 Y. OTMEZGUINE et al.

541

In the anterior perineal approach (38), used in three patients, the patient was placed in the lithotomy position. An anterior perianal transverse incision was made and the levator ani was exposed and freed. An anorectotomy was performed at 12 O’clock, up to 4-5 cm from the anal verge. The tumorectomy was completed and the edges of the resection were sutured longitudinally. After placement of the plastic tube loop by the radiotherapist, the rectotomy was closed. A myorraphy of the levator ani, followed by suture of the sphincter and skin closure, completed the procedure. A detailed description of the surgical techniques used will be the subject of another report. Curietherapy Following the tumorectomy, the edges of the excision were approximated longitudinally and the radiotherapist proceeded to place per operatively a plastic tube loop around the incision. Two needles, 15 cm long, were inserted in the peri-anal skin, at 0.5 cm from the anal verge and 2 cm apart. Note that the anal canal was dilated at this time and the spacing was reduced postoperatively. The needles were pushed to lie 3 mm deep to the mucosal surface and parallel about 7 mm on each side of the incision. The needles protruded 1 cm above the incision in the rectum and nylon monofilament was threaded through the needles to form a loop. The monofilament was substituted, using the pulling maneuver, by the plastic tube. The loop being formed, a monofilament was reintroduced to keep the plastic tube open and it was fixed by immobilization buttons. As soon as the histology was reported, usually 5 to 6 days later, a simulation film was taken and the loop was afterloaded with Iridium-192 wire with the branches ending 1 cm below each side of the tumorectomy incision. A plastic loop, inserted during a transphincteric approach, is shown in Figure 2. A loop with a separation of 14 to 18 mm was optimal, however, the spacing was frequently around 20 mm. According to the Paris System (7, 19), the dose is prescribed at the reference isodose corresponding to 85% of the basal dose rate calculated in the central plane of the implant. The basal dose rate varied because of the differences in linear activity of each Iridium192 wire and the differences in the spacing between the branches of the loops; it was influenced to a lesser degree by the active length of the loop. An example of a typical loop obtained and the isodoses on computerized dosimetry in the central plane are shown in Figures 3 and 4. Total active length was related to the tumorectomy wound which was proportional to the tumor diameter. The length treated was approximately 0.8X half total active length of the loop. For example, 12- 13 cm of active length would have been necessary for a scar 3.5-4 cm long resulting in a treated length of 4.8-5.2 cm. The thickness treated, measured in a direction perpendicular to the plane of the loop, was approximately 0.5X the spacing between the branches: in practice it varied from 8 to 10 mm. The width treated was approximately 1.75X the spacing between branches (19). The dose was pre-

Fig. 2. Diagram of a plastic tube loop inserted during a transphincteric local excision.

scribed according to the histology from the tumorectomy specimen; it was 20 Gy for Stage A and 25 Gy for Stage Bl and B2 tumors (1). No dose corrections were made for the various reference dose-rates (29). Follow-up The surveillance program included a physical examination and rectoscopy every 4 months for the first 2 years, and at longer intervals thereafter. Suspicious lesions were biopsied.

RESULTS Results of tumorectomies At the time of the resection, there was a reduction in tumor diameter greater than 50% in 76% ( 19/25) of cases, less than 50% in 16% (4/25) of cases, and complete disappearance of the tumor in two patients. The histological examination of the tumorectomy specimen revealed seven Stage A, eight Stage Bl, and ten Stage B2 carcinomas, using the Astler-Coller staging system (1). The excision was complete in all Stage A, in seven Stage Bl, and in five Stage B2 patients. Tumor was present at the resection line of one Stage Bl and five Stage B2 patients. Tumor control There were five local recurrences: none occurring in Stage A patients, two occurring in Stage B 1 patients, both with a complete resection, and three occurring in Stage B2 patients, of whom two had an incomplete resection. The local recurrences were all diagnosed at short intervals following the tumorectomy, the latest observed at 16

I. J. Radiation Oncology 0 Biology 0 Physics

542

Fig. 3. Verification

film of a peri-tumorectomy

September 1989, Volume 17, Number

loop placed per operatively

3

for interstitial boost: 20 or 25 Gy (Paris

System).

months. The two Stage Bl patients were salvaged by an abdominoperineal resection. Among the three Stage B2 patients, two had evidence of distant metastatic disease

Fig. 4. Computerized

at the time of local recurrence. The third patient had an APR, but unfortunately, developed liver metastases 1 year post salvage surgery. There was no local failure in fcxrr

dosimetry of Iridium-192 loop in the Paris System. 85% of the basal dose rate calculated in the central plane.

The reference

isodose corresponds

to

Rectal cancer 0 Y. OTMEZGUINEet al.

out of&x patients with incompletely resected tumors: one Stage B 1 patient and four Stage B2 patients. Finally, one Stage B 1 patient, with complete resection, developed distant metastatic disease without local recurrence. There were two local recurrences among the three patients resected by the anterior perineal approach (1 B2 grade 2 complete excision, 1 B2 grade 3 incomplete excision). The period at risk, the number of patients, and the local recurrences are displayed in Table 2. Complications There were two major complications: one recta-vaginal fistula which healed in 6 months, and one local necrosis which required a resection without colostomy. There were five minor complications consisting of five wound dehiscences, including two with minor necrosis. These all healed spontaneously within 2-3 months requiring only analgesics and stool softeners. Seven patients presented minimal rectorragia in the 12 months following treatment. The 20 patients with primary local control have preserved a full functional sphincter with normal defecation without tenesmus. There was no acute or chronic radiation enteritis or cystitis. The three patients requiring an abdominoperineal salvage procedure did not present any postoperative complications. DISCUSSION

The treatment of adenocarcinoma of the rectum must take into account the level of bowel wall penetration, nodal status, and whether the tumor is located above or below the peritoneal reflection (4, 13, 22,26, 35, 36, 37). A radical excision is basically the only way to assess the histopathological status of the regional lymphatics. Note that in the presence of Dukes C carcinoma, such radical surgery is rarely curative on its own, judging by the high local recurrence rate without adjuvant therapy in clinical (40-65%) and reoperative series (70%). For simplicity of reporting and because of its widespread use, we choose the Astler-Coller staging system (1) to classify our tumorectomy specimens. As no lymph nodes are removed, understaging is obvious and the terminology

Table 2. Local control: 25 patients Period at risk

No.

Local recurrences

1 to 2 yrs

7

1 @I)

2 to 3 yrs

5

2 (Bl, B2*)

3 to 4 yrs 4 to 5 yrs Plus 5 yrs

4 2 7

0 ; (B2*, B2)

B2* = Incomplete resection. All recurrences occured within 16 months following excision. One B 1 patient and five B2 patients with incomplete resection did not relapse with a follow-up of I8,3 1,32,40, and 86 months.

543

used by Whiteway et al. (39) consisting of submucosal, intramural, and extramural tumors would be more appropriate to classify our tumors. This inability to truly assess the regional lymphatics underlines one problem with any conservative approach. Preoperative irradiation is not advocated to alter the radical nature of the surgical intervention (12, 13, 15,25, 26, 34). Mohiuddin and Marks (23) showed excellent results of high dose preoperative irradiation in 28 patients with tumors 3 to 6 cm from the pectinate line (5-6 cm to 8-9 cm from the anal verge) to allow a sphincter saving procedure. They suggested, referring to the data of Pilipshen et al. (30), that LAR offers less local control than APR for tumors 0 to 11 cm from the anal verge, although no significant difference was noted by Pilipshen et al. in their large retrospective series: 14 1 APR versus 198 LAR. They felt that 5 cm or greater of distal clearance constituted an adequate margin (20) whereas others (31) including our surgeons, accept 2 cm as safe. Therefore, the number of these patients that could have been managed by an LAR with or without post-operative irradiation is not clear. In a recent update for cancer of the distal rectum (21) their criteria for safe margins have changed and, although it is difficult to compare with our experience, their strategy seems more suited for larger and higher tumors in patients fit for major surgery. In our series, regardless of tumor shrinkage obtained by external irradiation, APR was the only radical procedure possible for 2 1 patients. In general, the ability to truly preserve a functional sphincter, that is, the technical feasibility of LAR, dictates the choice of our surgeons between LAR and APR, and not the impression that APR offers better local control. The morbidity of radical excision, especially in the geriatric population ( 16), in addition to the problems previously mentioned, prompted us to develop this protocol of combined conservative management as an alternative to radical excision. This protocol is also a more comprehensive approach than simple local excision (3, 14, 17, 24, 39) electrocoagulation ( 18), laser therapy (9), or contact x-ray therapy (27, 32), which can be curative only in a selective group of patients (basically those with small submucosal lesions) who are difficult to identify clinically other than by being very restrictive. In this protocol, external irradiation is used to control regional subclinical disease and reduce the size of the tumor, whereas the perioperative endocurietherapy boost is designed to sterilize the tumor bed as a tumorectomy does not allow true safe margins. Tumors encompassing more than half the circumference of the rectum cannot be treated by this technique. This explains why most tumors (20/25, 80%) were polypoid or exophitic. The objectives of the local excision were easier to achieve when the tumor was not greater than 5 cm in its greatest diameter, when less than 30% of the circumference of the rectum was occupied by the tumor, and when the tumor was located

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within 8 cm from the anal verge. The anterior perineal approach (38) was necessary for three patients: three Stage B2 lesions of 4,4.5, and 6.5 cm in diameter. Excision was incomplete in two patients and there were two local recurrences, with one occurring in the patient with complete excision. In retrospect, tumors requiring this technique of excision may be “too big” for this conservative approach. The complications were acceptable with only one patient requiring a reintervention. There were five local failures, four of which occurred in patients who had originally

September 1989, Volume 17, Number 3

refused an APR. There were three salvage APRs; and two patients are alive and disease-free 1 year after salvage surgery, the third one is alive with liver metastatic disease 2 years after salvage surgery. In conclusion, the small number of patients and the short follow-up suggest caution in the use of this new approach. Nonetheless the small complication rate, the relative simplicity of the techniques, the good local control, and the possibility of salvage in patients who can undergo a major operation has encouraged us to pursue this combined approach.

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