Chemotherapy and radiation therapy for anal carcinoma. Survival and late morbidity

Proliferation parameters in epidermoid carcinomas of the anal canal

PURPOSE

In a prospective study, we assessed the proliferation parameters in primary epidermoid carcinomas of the anal canal, and results were compared with those in cervical carcinomas.

METHODS

Between January 1992 and December 1996, 32 patients with primary epidermoid carcinoma of the anal canal were studied prospectively. Patients were given i.v. bromodeoxyuridine and proliferation parameters were obtained using flow cytometry. The treatment protocol consisted of radiation therapy (XRT) (24 Gy/12-3.5 week split-28 Gy/14) and concurrent 5-fluorouracil and mitomycin C. Proliferation parameters were not obtained in six patients, leaving 26 patients in the analysis. There were 16 females and ten males, with two T1, 16 T2, five T3 and three T4 lesions. Median follow-up was 3.6 years. There were 22 squamous cell and four basaloid carcinomas. Six tumors were aneuploid.

RESULTS

Median values for T(s) and S-phase fraction were 7.7 h and 8.2%, respectively. The median LI was 6.8% (0.9-35.7%), and the median T(pot) was 4.1 days (0.9-30 days). There was no correlation of LI or T(pot) with gender, age, tumor stage, size or histology. Local failure was observed in five patients (T(pot)>4.1 days, n=3; LI>6.8%, n=4). Isolated regional failure or distant disease in the absence of local failure was not observed. The small number of outcome events precluded a definitive analysis of the prognostic role of LI and T(pot). Values for the proliferation parameters were similar to those in our updated study of patients with carcinoma of the uterine cervix (n=107), median LI of 6.7% and median T(pot) of 5.5 days.

CONCLUSIONS

We conclude that proliferation parameters in anal carcinomas are similar to those in cervical carcinomas. Rapid tumor proliferation does not have an apparent adverse impact on outcome in anal carcinomas managed by split-course XRT with concurrent 5-florouracil and mitomycin C.

An unusual late radiotherapy-related complication requiring surgery in anal canal carcinoma

We herein describe an unusual late radiation-related complication requiring surgery in a 60-year-old male affected by anal epidermoid carcinoma. The patient presented with obstructed defecation and ulcerated perianal lesions. The perianal biopsies were positive for anal squamous carcinoma. Transanal diagnostic investigations could not be performed because of anal stenosis. Computed tomography detected left inguinal lymphadenopathy and a nonhomogeneous presacral mass, infiltrating the rectal wall, the coccyx, and the sacrum. The patient underwent a colostomy, infusion of cisplatin and 5-fluorouracil, and irradiation of the pelvis, perianal region, and inguinal lymph nodes. In June 1997 the patient complained of the onset of continuous pain at the genitalia, and for penis necrosis he underwent penis amputation. The histologic examination was conclusive for postradiotherapy thrombosis. This complication could strengthen the hypothesis of vasculoconnective damage as the origin of long-term effects of radiotherapy. Probably the minimal dose in transit volume could not be achieved. Careful evaluation in choosing the treatment scheme is necessary if different options are available.

Carcinoma of the anal canal

Despite the rarity of carcinoma of the anal canal, remarkable progress has been achieved during the past 30 years in understanding its pathogenesis and improving treatment. Largely because of the rigorous collection of data and the treatment of patients in clinical trials, it is now widely accepted that the majority of cases are caused by human papillomavirus and can be cured by combination therapy. Concomitant treatment with external-beam radiation therapy and chemotherapy with fluorouracil and mitomycin represents the standard approach to combination treatment. Appropriate cytologic screening of high risk populations and the integration of platinum compounds into treatment regimens will most likely reduce mortality from this disorder even further.

Prognostic role of p53 protein expression in epidermoid carcinoma of the anal canal

PURPOSE

To assess the prognostic significance of p53 protein expression in patients with primary epidermoid carcinoma of the anal canal managed by radiation therapy (XRT), 5-fluorouracil (5-FU), and mitomycin C (MMC).

METHODS AND MATERIALS

From January 1991 to December 1993, 58 consecutive patients with primary epidermoid carcinoma of the anal canal were treated in a prospectively designed protocol of XRT (24 Gy/12--3(1/2) wk split--28 Gy/14) and concurrent 5-FU (1000 mg/m2/day 1-4) and MMC (10 mg/m2 day 1) of each cycle of XRT. Paraffin-embedded tumor samples were unavailable in 9 patients, leaving 49 patients in the study. Expression of p53 protein was studied using immunohistochemistry and quantified as percent tumor nuclei showing positive staining. Actuarial survival and disease-free survival (DFS) rates were estimated by the Kaplan-Meier method, and compared using the log-rank test. A Cox proportional hazard model was used for the multivariable analysis.

RESULTS

There were 6 T1, 26 T2, 7 T3, and 10 T4 lesions. Primary tumor sizes ranged from 1-15 cm with a median of 4 cm. There were 6 patients with nodal metastases. Median follow-up was 4.5 years. Positive nuclear immunostaining for p53 was observed in 40 of 49 patients. The median percent positive staining was 5%, with 13, 9, and 18 patients showing staining in <5%, 5 to <10%, and 10-50% of tumor nuclei respectively. There was no correlation of percent p53 staining with gender, age, tumor stage, size, or histology. Local, regional, and distant failures were observed in 12, 2, and 2 patients respectively. The 5-yr survival and DFS were 84% and 64% respectively. In univariate analysis, the only prognostic variable for survival was gender. For DFS, advanced T category and large tumor size were predictive of poor DFS. In multivariate analysis, poor DFS was associated with high T category (p = 0.0008), basaloid histology (p = 0.001), male gender (p = 0.002), and increasing percent of p53 protein expression (p = 0.01).

CONCLUSIONS

It is concluded that expression for p53 protein is present in a high percentage of patients with epidermoid carcinoma of the anal canal. For patients managed with combined XRT, 5-FU, and MMC, percent p53 protein expression is of prognostic value for DFS independent of other clinical factors such as T category, gender, and histology.

[Chemoradiotherapy in treatment of cancer of the anal canal]

In the treatment of anal canal carcinoma, since the work of Nigro, the 5-fluorouracil-mitomycin C regimen is considered standard when applied concomitantly with radiotherapy. Surgery is used mainly to salvage the failures after irradiation. Two randomized European trials (EORTC, UKCCCR) have shown that the 5-fluorouracil-mitomycin C combination improves local control but not overall survival. The RTOG-ECOG trial has shown that mitomycin C improves local control when compared to 5-fluorouracil alone. This chemotherapy is responsible for a toxic death in 2% of cases. The 5-fluorouracil-cisplatin regimen will possibly represent an alternative to the 5-fluorouracil-mitomycin C. Ongoing trials will help to answer this question.

Conservative treatment of anorectal tumors

PURPOSE

To evaluate the results of interstitial radiotherapy of anorectal tumors.

PATIENTS AND METHODS

From 1972 to 1993, one of the authors treated 45 patients by an interstitial implant for anorectal tumors. Of these, 33 patients suffered from primary tumors, 19 from squamous carcinoma, 2 from basaloid carcinoma of the anus and the other 12 from primary adenocarcinoma of the rectum. Of 12 patients treated for local recurrence, 10 had adenocarcinoma and 2 squamous cell carcinoma. Of the 33 patients with primary tumors, 27 received a course of external-beam radiotherapy before the implant. The median follow-up was 35 months.

RESULTS

Local response depended on the tumor volume treated. All 21 anal tumors showed complete response, 5 patients developed local recurrence and 4 distant metastases: 3 died from their disease. Of 12 rectal adenocarcinomas, 9 responded completely, 4 patients developed local recurrence and 4 distant metastases; 6 died from active disease. In the last group of 12 patients who were treated for recurrent tumors, 7 responded completely. One patient developed local recurrence and 9 distant metastases, only 4 are alive.

CONCLUSIONS

A combination of external-beam and interstitial radiotherapy is a relatively simple, non-mutilating, but well-tolerated and very effective method of treatment for early carcinoma of the lower rectum and anus.

Treatment of anal canal carcinoma with high dose radiation therapy and concomitant fluorouracil-cisplatinum. Long-term results in 95 patients

PURPOSE

To evaluate the long-term results of the treatment of anal canal carcinoma (ACC) with a combined concomitant radiochemotherapy (CCRT) treatment using fluorouracil (5 FU) and cisplatinum (CDDP) with a high dose of radiation therapy.

PATIENTS AND METHODS

Between 1982 and 1993 a series of 95 patients were treated. Staging showed a majority of advanced squamous ACC, i.e. 6 T1, 47 T2, 28 T3, 14 T4, 53 NO, 32 N1, 6 N2 and 4 N3. Irradiation was done with high dose external beam radiation therapy (EBRT) followed by a boost with 192 Iridium implant. During EBRT all patients received one course of 5 FU continuous infusion (1 g/m2/day, days 1-4) and CDDP (25 mg/m2/day, bolus days 1-4).

RESULTS

The median follow-up time was 64 months. At 5 and 8 years the overall survival was 84 and 77%, the cancer specific survival was 90 and 86% and the colostomy-free survival was 71 and 67%, respectively. The stage and the response of the tumor after EBRT were of prognostic significance. Patients with pararectal lymph nodes had an overall 5-year survival of 76% (versus 88% for non-N1). Among 78 patients who preserved their anus, the anal sphincter function was excellent or good in 72 (92%).

CONCLUSION

According to these results and recent randomized trials, CCRT appears as the standard treatment of ACC. Radical surgery should be reserved for local recurrence or persisting disease after irradiation. High dose irradiation in a small volume with concomitant 5 FU-CDDP appears to give a high rate of long-term local control and survival. Careful evaluation of pararectal nodes is essential for a good staging of the disease.

Impact of clinical and therapeutic factors on major late complications after radiotherapy with or without concomitant chemotherapy for anal carcinoma

PURPOSE

To investigate factors potentially influencing major late morbidity after sphincter-conserving treatment for anal carcinoma.

METHODS AND MATERIALS

Grade 3-4 complications were retrospectively analyzed in 144 evaluable patients (pts), 55 pts after split-course radiotherapy (RT), and 89 after concomitant chemo-RT. First sequence RT delivered a median dose of 39.6 Gy using megavoltage photon beams. Boost treatment used either 192Ir implantation or external beam RT (median dose 20 Gy). Chemotherapy started on day 1 and in 83% of pts consisted of Mitomycin-C (10 mg/m2) and a 5-day infusion of 5-fluorourcil (600-800 mg/m2/day). Uni- and multivariate analyses tested the association of following factors with complication rate: age, gender, stage, anatomic tumor extent, type of biopsy, external RT technique (dose, fraction size, field arrangement), boost type (brachytherapy vs. external), brachytherapy dose and dose rate, overall treatment time, and addition of chemotherapy.

RESULTS

Five-year actuarial complication rate was 16%. Two variables were significantly associated with complication rate: anatomic tumor extent (canal or margin vs. both +/- rectum; 10 vs. 31% complications, p = 0.0004) and first sequence prescribed dose (< 39.6 Gy vs. > or = 39.6 Gy; 7 vs. 23% complications, p = 0.012), confirmed as independent factors by Cox analysis. Grade 4 anal morbidity correlated significantly with prior local excision. All six bone complications were observed in pts treated by chemo-RT using large pelvic fields, five occurring in pts older than 66.

CONCLUSION

Pts with tumors involving more than one anatomic subsite or treated with the higher first sequence RT dose are at greater risk of major complications. Prior tumor excision and combined modality therapy in older pts appear to favor major anal and bone complications, respectively.

[Intracavitary afterloading therapy as a new technique of boost irradiation in anal canal carcinoma]

PURPOSE

There are different techniques of boost irradiation in the treatment of patients with anal carcinoma. A new system of applicators is presented, which can be used for an intracavitary afterloading therapy.

MATERIAL AND METHODS

Three different applicators are available, the first with a central catheter (K1), a second with 5 semicircular fixed catheters (K2) and an eccentric shield, a third with 8 circular fixed catheters and a central shield (K3).

RESULTS

The adequate choice of applicator and catheters takes into consideration the individual localisation and extension of anal carcinoma in planning therapy. Thus, in circular growing tumors, an irradiation of the whole circumference of the anal canal is possible. In non-circular growing tumors, the dose applied in the non-affected part of the anal canal can be reduced to a quarter of the dose applied at the tumor.

CONCLUSION

The new system of intracavitary afterloading therapy is a good alternative to previous techniques of boost irradiation in the treatment of anal carcinoma. By means of this technique, irradiation can be highly individualized, the tumor better included and non-affected sections of the anal canal saved.

The impact of treatment factors on local control in T2-T3 anal carcinomas treated by radiotherapy with or without chemotherapy

BACKGROUND

This study was conducted to investigate the influence of therapeutic parameters on local control (LC) in the sphincter-conserving treatment of T2-T3 anal carcinoma.

METHODS

From 1976 to 1993, 137 patients with anal carcinoma classified as T2 (85 patients) or T3 (52 patients) were treated curatively by radiotherapy (RT) alone (54 patients) or by concomitant chemotherapy and RT (83 patients). RT was delivered in two sequences, with a median gap of 46 days between the sequences. The first sequence was delivered at a median dose of 39.6 gray (Gy) using megavoltage photon beams. Boost treatment consisted of either 192Ir implantation or external beam RT (median dose, 20 Gy). Chemotherapy started on Day 1 and generally consisted of 1 cycle of mitomycin C (10 mg/m2) and a 5-day infusion of 5-fluorouracil (600-800 mg/m2/day). For surviving patients, median follow-up was 83 months. Univariate and multivariate analyses were performed to determine therapeutic parameters affecting LC after adjustment for clinical factors.

RESULTS

The 5-year actuarial LC was 76%. Factors associated with poorer LC (univariate) were as follows: age < 66 years (LC was 67% with the factor vs. 85% without), male gender (65% vs. 81%), tumor extent > 1/3 canal circumference (67% vs. 90%), lymph node involvement (64% vs. 81%), use of external beam boost (62% vs. 79%), and overall treatment time (OTT) > or = 75 days (69% vs. 85%). In multivariate analysis, no therapeutic parameters remained significant when adjusted for significant clinical factors, although OTT was of borderline significance (P = 0.09).

CONCLUSIONS

The results of this multivariate analysis suggest that therapeutic factors have a less marked effect on LC compared with clinical parameters; the only factor that appeared to have some effect was OTT. Efforts to improve LC in patients with poor prognoses should concentrate on optimizing OTT and the chemotherapeutic aspects of treatment (in other words, attempts should be made to provide more effective agents and optimize scheduling).

Chemotherapy and low-dose radiotherapy in the treatment of HIV-infected patients with carcinoma of the anal canal

PURPOSE

To determine the efficacy and tolerance of a standardized protocol of chemotherapy and low-dose radiotherapy in the treatment of anal cancer in human immunodeficiency virus (HIV)-infected patients.

METHODS AND MATERIALS

Between 1987 and 1995, eight HIV-positive patients with squamous cell carcinoma of the anal canal, four of whom had acquired immunodeficiency syndrome (AIDS), received therapy at the Kaiser Permanente Medical Center. All patients were treated using a combined modality approach consisting of low-dose radiotherapy (30 Gy in 15 fractions delivered 5 days/week), and chemotherapy [1000 mg/m2 of 5-fluorouracil (5-FU) delivered on days 1-4 and 29-32 as a continuous infusion over 96 h, and 10 mg/m2 of mitomycin C delivered as a bolus injection on day 1]. Patients have been followed from 4 to 81 months (mean 41, median 38).

RESULTS

All eight patients completed the therapy with minor variations to the protocol, and all have attained a clinical complete response. Four patients are alive and free of disease, and four died as a result of complications of AIDS, but remained free of anal carcinoma. There were no mortalities from the protocol and the morbidity was acceptable. Only one patient each was noted to have Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Grade 4 hematologic and gastrointestinal acute toxicity, and no Grade 4 skin toxicity was noted.

CONCLUSION

This combined therapy is effective for HIV-infected patients and appears to be tolerable with acceptable toxicities. It is best applied to patients who are HIV positive, or who have AIDS without concurrent major opportunistic infections. This approach is reasonable and affords patients a reasonably good chance at sphincter preservation by avoiding abdominoperineal resection. The optimal therapy for HIV-positive patients with advanced AIDS remains less well defined.

Role of Radiation Therapy and Fluoropyrimidines in the Treatment of Gastrointestinal Malignancies

BACKGROUND: The use of combined chemotherapy and radiation for gastrointestinal malignancies has several theoretical advantages, and clinical trials to determine the type and extent of clinical benefits have been performed. METHODS: The basic science and clinical trial data evaluating such combinations are reviewed, with an emphasis on the interactions between fluoropyrimidines and radiation. RESULTS: Improved outcomes from chemoradiotherapy have been demonstrated in patients with selected stages of anal, esophageal, rectal, and pancreatic cancer. CONCLUSIONS: Despite these positive results, further work is needed to demonstrate even more effective and less toxic treatment regimens.

Ten-year results of chemoradiation for anal cancer: focus on late morbidity

PURPOSE

To evaluate (a) long-term survival and (b) the incidence and nature of long-term morbidity/ mortality related to chemoradiation using the anal cancer experience.

METHODS AND MATERIALS

From January 1979 to April 1987,34 consecutive patients with Stage I (5 patients), II (15 patients), and II (14 patients) cancers of the anal canal were treated definitively with a chemoradiation regimen combining 41.4 Gy pelvic radiotherapy with two concurrent cycles of 5-fluorouracil and mitomycin C. Cumulative actuarial survival was calculated at 10 years and long-term morbidity was categorized per RTOG/EORTC late toxicity criteria. Specific criteria to grade anal toxicity were devised.

RESULTS

Cumulative survival for all 34 patients was 92% at 5 years and 85% at 10 years. The most frequent late toxicity was chronic diarrhea in 17 (50%) patients. Five patients (15%) had Grade 3 or 4 late toxicities. Sexual dysfunction was present in 2 of 26 evaluable patients (7%).

CONCLUSIONS

Excellent long-term survival and colostomy-free survival is possible for anal cancer patients treated definitively by chemoradiation. Late effects do not appear to be frequent or intense enough to deter the use of chemoradiation in anal cancer. The biologically expected increase in long-term toxicity when combining radiotherapy and chemotherapy is not substantiated by the results of this study.

Recent advances in radiation oncology

Radiotherapy remains an important component of the management of malignant disease. Especially when combined with cytotoxic chemotherapy, limited surgical excision, or both, irradiation has been shown to control disease in the primary site and regional nodes without the need for surgical extirpation as frequently as in past years. New developments in three-dimensional treatment planning and the precise delivery of high-dose radiation promise to increase the benefit of radiation treatment. Finally, molecular studies of the cell's response to radiation and the phenomena of DNA damage and repair are providing explanations for heretofore unexplained radiobiologic observations. Such research is laying the groundwork for targeted manipulation of the cell's response to radiation, which will be tested in the near future.

Conservative versus nonconservative treatment of epidermoid carcinoma of the anal canal for tumors longer than or equal to 5 centimeters. A retrospective comparison

BACKGROUND

The role of radiotherapy alone in the sterilization of anal canal epidermoid carcinomas of 5 cm or more remains to be assessed. Thus, the outcomes of patients treated with radiotherapy alone (RT) versus those treated with preoperative radiotherapy and surgery (RS) were compared retrospectively.

METHODS

Between 1972 and 1990, 185 patients were treated with curative intent either with RT alone (n = 147) or with RS (n = 38). The Mean tumor length was 6.18 +/- 1.14 cm and was significantly longer in the RS group (6.55 +/- 1.29 cm) than in the RT group (6.08 +/- 1.08 cm) (P = 0.02). The median follow-up was 77 +/- 57 months and 93 +/- 60 months (P = 0.23) for the RT and RS groups, respectively. For the RT group, the first course of radiotherapy was 40 to 45 Gy in the pelvis for 4 to 5 weeks; after a rest of 4 to 6 weeks, radiotherapy was boosted an additional 15 to 20 Gy for 2 weeks. The RS patients received 40 to 45 Gy in the pelvis for 4 to 5 weeks, then received surgery after a median period of 54 days.

RESULTS

The overall 10-year cancer specific survival rates were 58% in the RT group and 66% in the RS group (P = 0.48). The T-stage 10-year cancer specific survival rates were 68% in the RT group and 67% in the RS group for T2 tumors (P = 0.96); 57% in the RT group and 53% in the RS group for T3 tumors (P = 0.85); and 42% in the RT group and 40% in the RS group for T4 tumors (P = 0.05). In the RS group, the local control rate was 75% (3/4) for T2 tumors; 74% (17/23) for T3 tumors; and 82% (9/11) for T4 tumors. In the RT group, the local control rate was 77% (34/44) for T2 tumors; 70% (58/82) for T3 tumors; and 60% (12/20) for T4 tumors. In the RT group, the anal conservation rate was 61% (27/44) for T2 tumors, 59% (48/82) for T3 tumors, and 55% (11/20) for T4 tumors. Local tumoral control and a functioning anus were present in 72 out of 147 (49%) patients [52% (23/44) for T2 patients, 52% (43/82) for T3 tumors, and 30% (6/20) for T4 patients]. In the RS group, the grade 3 complication rate was 9% (13/146) and in the RS group, 5% (2/38).

CONCLUSION

For patients with T4 tumors, preoperative radiotherapy and surgery seemed to be better in terms of survival and local tumor control rate, but the difference was not significant probably because the number of patients in the RS group was small. For these large tumors, the treatment should probably be more aggressive, combining chemotherapy and radiation therapy, but the increase of local control in relation with the addition of cytotoxic chemotherapy to irradiation is not proved.

Anal carcinoma--a histological review

Epidemiological evidence of an association between anal carcinoma and symptomatic HIV-related disease suggests that the number of cases of this disease may increase significantly over the next few years. The role of oncogenic HPV types in the pathogenesis of anal carcinoma is substantiated by both epidemiological evidence that tumours are associated with a past history of anal warts and by experimental evidence showing that over 85% of tumours contain HPV 16/18 DNA on PCR. The physical state of the virus in the tumour cell genome is currently under investigation, and cellular interactions between HPV, HIV and other sexually transmitted viruses require further research. Clinical studies have shown that patients with anal warts and those who are HIV positive also show an increased tendency to develop dysplasia within the anal epithelium. However, the malignant potential of dysplasia remains unclear and, it presents problems in management, particularly when multifocal and high grade. Problems in classification of anal carcinomas involve both the site of the tumours and the histological appearance. Despite the difficulties which exist in estimating the origin of a tumour from canal or margin, this information does appear to have clinical significance and should therefore continue to be assessed. Recent morphological and keratin studies have emphasized the heterogeneity of these tumours and have revealed a similar heterogeneous profile of keratin expression in the normal anal epithelium. These results support the body of opinion which suggests that, with the exception of small cell carcinoma and adenocarcinoma, anal carcinomas should be considered as squamous cell tumours which are able to display a range of further morphological characteristics within which ductal differentiation and mucin production appear to carry the worst prognosis. Although there is no universally accepted staging system for anal carcinoma, depth of invasion and extent of spread at the time of diagnosis are the most important clinical factors determining survival and response to therapy. Randomized clinical trials are now under way to compare the outcome of various combinations of radiotherapy and chemotherapy, which have replaced radical surgery as a first line treatment and resulted in a significant decrease in patient morbidity from this disease.

Combination therapy for epidermoid carcinoma of the anal canal

PURPOSE

This study was designed to assess results of chemoradiation therapy for epidermoid carcinoma of the anal canal.

METHODS

A retrospective review of records of the prospective database revealed 35 patients who had been diagnosed with anal canal carcinoma and treated with chemoradiotherapy at Wilford Hall USAF Medical Center (tertiary referral hospital) from 1981 to 1991.

RESULTS

Patients ranged in age from 35 to 80 (mean, 59) years, and 63 percent were women. Primary tumors ranged from 1 to 8 cm in diameter (mean, 3 cm). The first six patients had an abdominoperineal resection (APR) after chemoradiotherapy, and no residual tumor was identified in the specimens. In the subsequent 29 patients who did not have APR, 5 had moderate problems with anal continence, and one required a diverting colostomy for incontinence. Follow-up ranged from 4 months to 12.9 years (mean, 5.2 years). There were two pelvic recurrences, and three patients developed distal metastasis. Eight patients died during follow-up, including three with recurrent or persistent disease. Five-year survival using life-table analysis was 89 percent.

CONCLUSION

Long-term follow-up confirms that chemoradiation remains the preferred therapy for epidermoid carcinoma of the anal canal.

Endoanal ultrasonography in the follow-up of anal carcinoma

As the modern treatment for anal carcinoma is either radiotherapy alone or combined radiochemotherapy, an exact histological staging is impossible. Therefore we have to depend on an accurate preoperative staging method. Endoanal ultrasonography enables imaging of the normal anal canal and its pathologies. In a prospective investigation we were able to confirm the histological proven diagnosis of an anal epidermoid carcinoma in 12 patients with a 10-MHz transducer covered with a sonolucent plastic cone. The depth of infiltration can be determined in relation to the normal layers of the anal canal. Six patients treated with radiotherapy alone or combined radiochemotherapy were followed and the success or failure of the treatment was documented. Endosonography of the anal canal allows an exact staging of a primary anal carcinoma and the follow-up in irradiated carcinomas. Besides digital palpation and proctoscopy with biopsy, endosonography complements the preoperative staging of anal carcinomas.

Recurrent squamous cell carcinoma of the anal canal. Predictors of initial treatment failure and results of salvage therapy

OBJECTIVE

The outcomes of patients with squamous cell carcinoma of the anal canal treated by either sphincter-preserving procedures or radical surgery were evaluated, with the goals of identifying factors predicting treatment failure and quantifying results of salvage therapy in patients with recurrent disease.

BASIC PROCEDURES

A population-based study on all patients in all 159 hospitals of the Department of Veterans Affairs (VA) from 1987 to 1991 was carried out. Data were compiled from several national computerized VA data sets. Supplementary information from local tumor registrars also was obtained, including demographic information, discharge summaries, operative reports, pathology reports, and medical oncology and radiation oncology summaries. From these sources, information on tumor histology, tumor stage, tumor grade, presence of regional or distant metastases, surgical procedures, use of chemotherapy and radiation therapy (RT), toxicity of chemotherapy and RT, development of recurrent disease, treatment of recurrence, survival, and cause of death were obtained.

MAIN FINDINGS

Four hundred five patients with anal cancer were identified by computer search, and 204 (51%) were evaluable; 164 of 204 (80%) had squamous cell carcinoma, 137 of whom (84%) were treated with sphincter-preserving procedures, and 27 of whom (16%) were treated by by radical surgery. One hundred fourteen of 138 (83%) were treated by multimodality therapy, which we defined as local excision followed by chemotherapy and RT. The mean dose of RT among patients treated by multimodality therapy was 4200 +/- 540 cGy and 82% of those treated with multimodality therapy received 5-FU/mitomycin C. Recurrent disease was diagnosed in 43 of all 149 patients (29%) with potentially curable disease. (stages I-III) Multivariate analysis revealed that stage at diagnosis (p = 0.04) and method of treatment (p = 0.03) were the sole predictors of recurrence. Fifty-three percent of patients who underwent salvage abdominoperineal resection (APR) are alive, whereas only 19% who underwent salvage chemotherapy with or without RT are alive.

PRINCIPAL CONCLUSIONS

These data indicate that multimodality therapy currently is being employed in the majority of patients with squamous cell carcinoma of the anal canal in the VA system. Tumor stage and method of treatment appear to affect the likelihood of development of recurrent disease. Salvage APR has curative potential. Results with salvage chemotherapy and RT are disappointing.

Malignant anal tumours

Anal tumours represent 5 per cent of anorectal cancers and exist as two clinical entities: tumours of the anal canal and those of the anal margin. Smoking and sexual behaviour, particularly homosexual anal intercourse, are important aetiological factors. This association is related to anal warts and human papillomavirus infection, notably type 16, which is found in around 70 per cent of warts. Symptoms are non-specific and are frequently attributed to benign conditions. Rectal examination reveals a characteristically infiltrating lesion and any suspicious anal area should be biopsied. There are two histological types. Squamous carcinoma comprises approximately 95 per cent of anal tumours and includes the 35 per cent of tumours derived from the anal transition zone (cloacogenic tumours), containing a mixture of squamous and mucinous elements. The remaining 5 per cent of anal tumours are adenocarcinoma. Squamous cell tumours of the anal canal are probably best treated using radiotherapy (with chemotherapy) as complete response rates, 5-year survival rates, and incidences of normal sphincter function and significant toxicity are around 80, 70, 75 and 20 per cent respectively. Treatment failures may be salvaged by surgery. The 5-year survival and local recurrence rates for radical surgery are around 60 and 25 per cent respectively; there are few indications for local excision. In contrast, 60 per cent of anal margin tumours are suitable for local excision, the 5-year survival rate being in excess of 80 per cent. Combining radiotherapy with surgery may give additional benefit. Current randomized controlled trials should further clarify the relative merits and demerits of the treatment options.

Epidermoid carcinoma of the anal canal. Results of curative-intent radiation therapy in a series of 270 patients

BACKGROUND

Epidermoid carcinoma of the anal canal is an uncommon disease, and most institutions have only a small series of patients. The current study of a large series of patients treated with radiation therapy in a single institution evaluates the outcome, prognostic factors, and the late complications for these patients.

METHODS

From 1972 to 1991, 270 patients with anal canal epidermoid carcinoma without evident distant metastasis were irradiated with curative intent in the Radiotherapy Department of Tenon Hospital. The sex ratio was 1 man/5.7 women, with a mean age of 67.5 years. The histology included 59.6% well-differentiated epidermoid carcinoma, 32.2% moderately or poorly differentiated epidermoid carcinoma, and 8.2% cloacogenic. The T-classification was: T1: 8.5%; T2: 51.1%; T3: 30.4%; T4: 10%. Abnormal inguinal lymph nodes were present in 12.5% of the patients. Patients were irradiated by external beam. They received a first course of photon irradiation consisting of (mostly 18 mV or 25 mVl; some Co60 or 6 mV) 40-45 Gy (box technique) in the pelvis for 4-5 weeks. After a rest of 4-6 weeks, a second course of 15-20 gy in 2 weeks was given through a perineal field by an electron beam of suitable energy. When rectal involvement was important, a four-field, small box technique was used. Fourteen patients were given a booster irradiation of 30 Gy by interstitial brachytherapy (Iridium 192 sources), and four patients were treated with interstitial brachytherapy alone, to a mean dose of 62.5 Gy.

RESULTS

At 5 and 10 years, determinate survival rates were: T1: 86% and 86%; T2: 86.2% and 82.5%; T3: 60.1% and 56.8%; T4: 45% and 45%, respectively. The overall local control rate was 80%. The overall anal conservation rate was 67%. In 154 patients (57%), the anus had maintained its normal function. At 5 and 10 years, determinate survival was 76% and 73.7%, respectively, for N0 and 53.5 and 53.5% for clinically involved inguinal lymph nodes. According to the log-rank test, survival comparisons between T2 and T3 classifications and of tumor sizes less than or equal to 4 cm in length and greater than or equal to 5 cm in length were significant (P = 0.0001 and P < 0.0001, respectively). The presence of clinical abnormal inguinal lymph nodes had a significant negative influence on survival rates (P = 0.047). Multivariate analysis indicated that T-classification and tumor size in centimeters were the only predictive variables. Nonpredictive variables included nodal status, histology, age, total dose, overall treatment time, and irradiation technique. The grade 3 complication rate requiring surgical treatment was 27/270 (10%), considering all patients (27/190 represents a 14% rate for patients who had local tumor control after radiation therapy alone without secondary salvage amputation). There was no significant relationship between complication rate and the aforementioned variables. Because of the homogeneity of the irradiation doses, no significant relationship was found between dose, local control rate, or complication rate.

CONCLUSIONS

After radiation therapy, recognizing the distinction between tumor sizes of less than or equal to 4 cm in length and more than 4 cm in length (which is not considered in TNM Classification criteria [International Union Against Cancer, 1987]) could help to improve treatment strategies. For tumors more than 4 cm in length and/or with clinically involved lymph nodes, the treatment should be more extensive with combined chemotherapy and radiation therapy, but the increased local control with the addition of cytotoxic chemotherapy to irradiation has not been proven.

[Cancer of the anal canal; role of radiotherapy and combinations of chemotherapy and radiotherapy]

Carcinoma of the anal canal is a rare disease, more common in women than in men. The mean age distribution at presentation is about 60 years. The natural history is mainly loco-regional, distant metastases being uncommon. Histologically, most cancer are of the squamous cell type of different keratinization. The pre treatment evaluation is mainly performed by methodical clinical examination. There is no widely accepted staging system for these tumours. Three statistically significant prognostic factors are admitted: tumour size, regional nodal involvement and histological grade. The french school (Tenon, Institut Gustave Roussy, Institut Curie, Lyon) and the experience at the "Princess Margaret Hospital" at Toronto have shown that irradiation of these tumours is an adequate therapy. In Europe, irradiation has always played a more important role in the therapy of these tumours, than in North America where surgery was often preferred as the initial therapy. With the introduction of combined modality treatment, the use of pre-operative concomitant radiochemotherapy, in North America, has again changed the treatment policy towards a conservative radiotherapeutic approach. The present study analyses the modalities and the results from radiation therapy alone and the preliminary results from concomitant irradiation and chemotherapy.

Treatment of relapsing anal carcinoma

Between 1983 and 1989, a total of 94 patients were admitted to the Norwegian Radium Hospital for primary squamous cell carcinoma (including 'basaloid' and 'cloacogenic' carcinomas) of the anal canal. Seven patients with evident distant metastases received chemotherapy, while without known distant metastases received combined chemo- and radiotherapy. Of the latter patients, 17 developed distant metastases and 11 local recurrence later on. Patients with distant metastases had a median survival of 12 months (range 3-54 months) following start of chemotherapy (cisplatin + 5-FU or mitomycin C + 5-FU). An abdominoperineal resection was performed on 9 of the 11 patients with local relapse. Of these, 6 patients were alive without evident disease after 3 years of observation.

Diagnosis and treatment of anal carcinoma. An overview

Squamous cell carcinoma of the anal canal gives early symptoms and is easy to diagnose. However, these patients often present with advanced tumours, probably because of patient's and/or doctor's delay. The diagnosis must be confirmed by a conclusive biopsy as the treatment of ano-rectal tumours is based upon correct histopathological diagnosis. Loco-regional tumour control of squamous cell carcinoma is excellent following radiotherapy or combined chemoradiotherapy as only 10-20% of the patients develop a local recurrence. The great majority of these are cured by abdominoperineal resection. However, this treatment involves considerable acute and chronic toxicity, but mortality is less than 2%. There is no general agreement about how to minimize toxicity without hazarding loco-regional tumour control. One way could be to irradiate only the primary tumour site in patients with early lesions, and reserve radiotherapy of regional lymph nodes for more advanced cases. About 20% of the patients develop distant metastases, which make the disease incurable. Hence, frequent, rectal digital examination is the most important follow-up since early local recurrences can easily be cured. There is no general consensus concerning adjuvant chemotherapy, but its potential should be further explored.