Rate and treatment of pelvic recurrence after abdominoperineal resection and low anterior resection for rectal cancer

Potentiating the effects of radiotherapy in rectal cancer: the role of aspirin, statins and metformin as adjuncts to therapy

BACKGROUND

Complete tumour response (pCR) to neo-adjuvant chemo-radiotherapy for rectal cancer is associated with a reduction in local recurrence and improved disease-free and overall survival, but is achieved in only 20-30% of patients. Drug repurposing for anti-cancer treatments is gaining momentum, but the potential of such drugs as adjuncts, to increase tumour response to chemo-radiotherapy in rectal cancer, is only just beginning to be recognised.

METHODS

A systematic literature search was conducted and all studies investigating the use of drugs to enhance response to neo-adjuvant radiation in rectal cancer were included. 2137 studies were identified and following review 12 studies were extracted for full text review, 9 studies were included in the final analysis.

RESULTS

The use of statins or aspirin during neo-adjuvant therapy was associated with a significantly higher rate of tumour downstaging. Statins were identified as a significant predictor of pCR and aspirin users had a greater 5-year progression-free survival and overall survival. Metformin use was associated with a significantly higher overall and disease-free survival, in a subset of diabetic patients.

CONCLUSIONS

Aspirin, metformin and statins are associated with increased downstaging of rectal tumours and thus may have a role as adjuncts to neoadjuvant treatment, highlighting a clear need for prospective randomised controlled trials to determine their true impact on tumour response and overall survival.

Anterior resection for rectal cancer with mesorectal excision: institutional review

This study aims to compare the operative results and oncological outcomes of patients with total mesorectal excision (TME) for mid and distal cancer and partial mesorectal excision (PME) for proximal cancer. Anterior resection has become the preferred treatment option for rectal cancer. TME with sharp dissection has been shown to be associated with a low local recurrence rate. Controversies still exist as to the need for TME in more proximal tumor. Resection of primary rectal and rectosigmoid cancer was performed in 298 patients from January 2003 to November 2010. These 298 patients (163 men and 135 women; median age, 67 years) underwent anterior resection. The curative resection was performed in 269 patients (90.3 %). TME was performed in 202 patients (67.8 %). Significantly longer median operating time, more blood loss, and a longer hospital stay were found in patients with TME. The overall operative mortality and morbidity rates were 1.8 % and 32.6 %, respectively, and there were no significant differences between those of TME and PME. Anastomotic leak occurred in 8.1 % and 1.3 % of patients with TME and PME, respectively (P < 0.001). Independent factors for a higher anastomotic leakage rate were TME, the malegender, the absence of stoma, and increased blood loss. The advanced stage of the disease and the performance of coloanal anastomosis were independent factors for increased local recurrence. By performing TME in patients with mid and distal rectal cancer, the local control and survival of these patients are similar to those of patients with proximal cancers where adequate clearance can be achieved by PME.

Extended abdominoperineal excision vs. standard abdominoperineal excision in rectal cancer--a systematic overview

BACKGROUND

After introduction of total mesorectal excision (TME) as the gold standard for rectal cancer surgery, oncologic results appeared to be inferior for abdominoperineal excision (APE) as compared to anterior resection. This has been attributed to the technique of standard APE creating a waist at the level of the tumor-bearing segment. This systematic review investigates outcome of both standard and extended techniques of APE regarding inadvertent bowel perforation, circumferential margin (CRM) involvement, and local recurrence.

METHODS

A literature search was performed to identify all articles reporting on APE after the introduction of TME using Medline, Ovid, and Embase. Extended APE was defined as operations that resected the levator ani muscle close to its origin. All other techniques were taken to be standard. Studies so identified were evaluated using a validated instrument for assessing nonrandomized studies. Rates for perforation, CRM involvement, and local recurrence were compared using chi-square statistics.

RESULTS

In the extended group, 1,097 patients, and in the standard group, 4,147 patients could be pooled for statistical analysis. The rate of inadvertent bowel perforation and the rate of CRM involvement for extended vs. standard APE was 4.1% vs. 10.4% (relative risk reduction 60.6%, p = 0.004) and 9.6% vs. 15.4% (relative risk reduction 37.7%, p = 0.022), respectively. The local recurrence rate was 6.6% vs. 11.9% (relative risk reduction 44.5%, p < 0.001) for the two groups.

CONCLUSION

This systematic review suggests that extended techniques of APE result in superior oncologic outcome as compared to standard techniques.

A systematic review of cancer related patient outcomes after anterior resection and abdominoperineal excision for rectal cancer in the total mesorectal excision era

PURPOSE

It is a widely held view that anterior resection (AR) for rectal cancer is an oncologically superior operation to abdominoperineal excision (APE). However, some centres have demonstrated better outcomes with APE. We conducted a systematic review of high-quality studies within the total mesorectal excision (TME) era comparing outcomes of AR and APE.

METHODS

A literature search was performed to identify studies within the TME era comparing AR and APE with regard to the following: circumferential resection margin (CRM) status, tumour perforation rates, specimen quality, local recurrence, overall survival (OS; 3 or 5 year), cancer-specific survival (CSS) and disease-free survival (DFS). Additional data regarding patient demographics and tumour characteristics was collected.

RESULTS

Twenty four studies fulfilled the eligibility criteria with Newcastle-Ottawa scores of six or greater. Where a significant difference was found, all studies reported lower and more advanced tumours for APE and 4/5 studies observed more frequent use of neoadjuvant and adjuvant therapies in APE patients. Tumour perforation rates and CRM involvement where reported, were significantly greater for APE. 8 out of 10 studies showing significant differences in local recurrence reported higher rates for APE but no differences were observed with distant recurrence. Where differences were noted, AR was reported to have increased DFS, CSS and OS compared to APE.

CONCLUSIONS

Patients treated with AR have lower rates of tumour perforation and CRM involvement and tend to have better outcomes with regard to disease recurrence and survival. However, tumours treated by APE are lower and more locally advanced.

Impact of neoadjuvant treatment on total mesorectal excision for ultra-low rectal cancers

Background

This study reviewed the impact of pre-operative chemoradiotherapy or post-operative chemotherapy and/or radiotherapy on total mesorectal excision (TME) for ultralow rectal cancers that required either low anterior resection with peranal coloanal anastomosis or abdomino-perineal resection (APR). We examined surgical complications, local recurrence and survival.

Methods

Of the 1270 patients who underwent radical resection for rectal cancer from 1994 till 2007, 180 with tumors within 4 cm with either peranal coloanal anastomosis or APR were analyzed. Patients were compared in groups that had surgery only (Group A), pre-operative chemoradiotherapy (Group B), and post-operative therapy (Group C).

Results

There were 115 males and the mean age was 65.43 years (range 30-89). APR was performed in 134 patients while 46 had a sphincter-preserving resection with peranal coloanal anastomosis. The mean follow-up period was 52.98 months (range: 0.57 to 178.9). There were 69, 58 and 53 patients in Groups A, B, and C, respectively. Nine patients in Group B could go on to have sphincter-saving rectal resection. The overall peri-operative complication rate was 43.4% in Group A vs. 29.3% in Group B vs. 39.6% in Group C, respectively. The local recurrence rate was significantly lower in Group B (8.6.9% vs. 21.7% in Group A vs. 33.9% in Group C) p < 0.05. The 5-year cancer-specific survival rates for Group A was 49.3%, Group B was 69.9% and Group C was 38.8% (p = 0.14).

Conclusion

Pre-operative chemoradiation in low rectal cancer is not associated with a higher incidence of peri-operative complications and its benefits may include reduction local recurrence.

Laparoscopic versus Open Total Mesorectal Excision: A Nonrandomized Comparative Prospective Trial in a Tertiary Center in Mexico City

Because definitive long-term results are not yet available, the oncologic safety of laparoscopic surgery in rectal cancer remains controversial. Laparoscopic total mesorectal excision (LTME) for rectal cancer has been proposed to have several short-term advantages in comparison with open total mesorectal excision (OTME). However, few prospective randomized studies have been performed. The main purpose of our study was to evaluate whether relevant differences in safety and efficacy exist after elective LTME for the treatment of rectal cancer compared with OTME in a tertiary referral medical center. This comparative nonrandomized prospective study analyzes data in 56 patients with middle and lower rectal cancer treated with low anterior resection or abdominoperineal resection from November 2005 to November 2007. Follow-up was determined through office charts or direct patient contact. Statistical analysis was performed using χ2 test and Student's t test. Twenty-eight patients underwent LTME and 28 patients were in the OTME group. No conversion was required in the LTME group. Mean operating time was shorter in the laparoscopic group (LTME) (181.3 vs 206.1 min, P < 0.002). Less intraoperative blood loss and fewer postoperative complications were seen in the LTME group. Return of bowel motility was observed earlier after laparoscopic surgery. There was no 30-day mortality and the overall morbidity was 17 per cent in the LTME group versus 32 per cent in the OTME group. The mean number of harvested lymph nodes was greater in the laparoscopic group than in the OTME group (12.1 ± 2 vs 9.3 ± 3). Mean follow-up time was 12 months (range 9-24 months). No local recurrence was found. LTME is a feasible procedure with acceptable postoperative morbidity and low mortality, however it is technically demanding. This series confirms its safety, although oncologic results are at present comparable with the OTME published series with the limitation of a short follow-up period. Further randomized studies are necessary to evaluate long-term clinical outcome.

Prognostic significance of circumferential resection margin following total mesorectal excision and adjuvant chemoradiotherapy in patients with rectal cancer

BACKGROUND

This study was designed to evaluate the prognostic value of circumferential resection margin (CRM) in rectal cancer patients who underwent curative resection with adjuvant chemoradiotherapy (CRT).

METHODS

We studied 504 patients who underwent total mesorectal excision with adjuvant CRT for rectal cancer between 1997 and 2001. The patients were divided into two groups: a negative CRM group (CRM > 1 mm) and a positive CRM group (CRM <or= 1 mm). The survival rates, local recurrence rates, and systemic recurrence rates were compared between groups.

RESULTS

The negative CRM group had 460 patients and the positive CRM group had 44 patients. The 5-year local and systemic recurrence rates were 11.3 and 25.3%, respectively, in the negative CRM group and 35.2 and 60.8% in the positive CRM group, respectively. The cancer-specific 5-year survival rates for the two groups were 72.5 and 26.9% (P < .001), respectively. CRM was found to be an independent prognostic factor by multivariate analyses which were adjusted for known outcome predictors (P < .001).

CONCLUSION

Oncological outcome for patients in the positive CRM group is less favorable than for those in the negative CRM group. Adjuvant CRT is not a definite treatment modality that can be used to compensate for a positive CRM following TME and adjuvant CRT in patients with TNM stage II or III rectal cancer.

Surgical outcomes after total mesorectal excision for rectal cancer

BACKGROUND AND OBJECTIVES

This study reviewed the results of surgery for distal rectal cancer following the introduction of total mesorectal excision (TME) for rectal cancer.

METHODS

Two hundred sixty-four patients who had undergone elective curative surgical resection of rectal cancer within 12 cm of the anal verge were included. Comparisons were made between patients who had different surgical procedures.

RESULTS

The overall operative mortality rate was nil, and the morbidity 39.4%. With a mean follow-up of 34 months (range 5-105 months), local recurrence occurred in 21 of the patients. The 3- and 5-year actuarial local recurrence rates were 9% and 12%, respectively for the whole group. Abdominoperineal resection (APR) was necessary in 65 of 264 (24.6%) of the patients, with a very low local recurrence rate in this subgroup (5% at 3 years). On multivariate analysis, only stage was a significant prognosticator of overall survival (P = 0.012).

CONCLUSIONS

With the practice of TME, APR was still necessary in 25% of patients with rectal cancer within 12 cm of the anal verge. Type of surgery and tumor distance from the anal verge influenced local recurrence rates, but only initial tumor stage was associated with long-term survival.

Endorectal ultrasound-directed biopsy: a useful technique to detect local recurrence of rectal cancer

AIMS

This study assesses the value of endorectal ultrasound (ERUS)-directed biopsy in detecting local recurrence of rectal cancer.

METHODS

We reviewed the records of patients undergoing ERUS by a single surgeon for surveillance after treatment of rectal adenocarcinoma. Lesions suggestive of local recurrence underwent ERUS-assisted core-needle biopsy (EAB) via a proctoscope after precise ERUS localization or direct ERUS-guided biopsy (EGB) via a B&K Medical probe.

RESULTS

From 1991 to 2003, 525 patients underwent 2,490 surveillance ERUS. Of these patients, 51 underwent 62 biopsy sessions: 36 EGB and 26 EAB. The mean age of patients was 67.2 years (range 38-93 years); 22 (43%) were female. Only 11 patients (22%) had undergone prior radical resection of their primary tumor. No patient experienced a complication from the biopsies despite five being anticoagulated. Of 39 patients whose cancer recurrence was documented during follow-up, 32 (82%) were diagnosed at the initial biopsy session, and in five (13%), recurrence was detected only with ERUS. The combined sensitivity, specificity, and accuracy of EAB and EGB in detecting recurrence was 83, 100, and 87%, respectively. In 26 patients with local recurrence, resection was performed with curative intent.

CONCLUSION

ERUS with biopsy is useful in detecting local recurrence after treatment of rectal cancer. It is safe, with a high diagnostic yield. It may be particularly useful in patients at higher risk for local recurrence (i.e., after endocavitary radiation and local excision) and may allow early detection of local recurrence, thereby permitting attempts at curative resection.

Estándares de calidad de la cirugía del cáncer de recto

The results of surgery for rectal cancer have classically been measured through indicators such as morbidity, mortality, and length of hospital stay. In the last few years other parameters have been included that evaluate healthcare quality such as the functional results of the surgical technique employed and quality of life. Total resection of the mesorectum, performed by experienced surgeons, is the surgical technique of choice. Currently, the sphincter can be preserved in 70% of patients. Anastomotic dehiscence after anterior resection of the rectum is the most serious complication and the most important risk factor is the height of the anastomosis. The overall dehiscence rate should be less than 15% and operative mortality should be between 2% and 3%. The colonic reservoir improves functional outcome and consequently it is the procedure of choice to reconstruct transit after low anterior resection. Local recurrence should be less than 10% and 5-year survival should be between 70% and 80%. In general, quality of life is better after anterior resection of the rectum than after abdominoperineal amputation, despite the functional deterioration presented by some patients.

Results of treatment of distal rectal carcinoma since the introduction of total mesorectal excision: a single unit experience, 1994-2003

BACKGROUND AND AIMS

This study reviewed the results of surgery for distal rectal cancer (where the tumour was within 6 cm of the anal verge) following the introduction of total mesorectal excision for rectal cancer in one institution.

PATIENTS AND METHODS

One hundred and fifty-three patients who had undergone elective curative surgical resection of rectal cancer within 6 cm of the anal verge were included. The demographic, operative and follow-up data were collected retrospectively. Comparisons were made between patients who had different surgical procedures.

RESULTS

The overall operative mortality rate was nil, and the morbidity 41%. With a mean follow-up of 37 months (range 5-100 months), local recurrence occurred in 18 of the patients. The 5-year actuarial local recurrence rates for double-stapled anastomosis, low-strength anastomosis and abdominoperineal resection (APR) were 39, 17 and 11% respectively. The local recurrence rate was significantly higher for double-stapled low anterior resection than for the other types of operation (P=0.007). On multivariate analysis type of surgery (P=0.025) and tumour stage (P=0.043), were associated with local recurrence, but only stage was a significant prognosticator of overall survival (P=0.0006).

CONCLUSION

With the practice of total mesorectal excision, APR was still necessary in 40% of patients with rectal cancer within 6 cm of the anal verge. The local recurrence rate was lower in patients treated with APR than in those with double-stapled low anterior resection; however, survival rates were similar in these two groups.

Outcome of anterior resection for stage II rectal cancer without radiation: the role of adjuvant chemotherapy

BACKGROUND

This study aimed to evaluate the oncological outcome of patients who had Stage II rectal cancer and underwent curative nonsphincter-ablation surgery without adjuvant radiation.

PATIENTS AND METHODS

During the study period from August 1993 to December 2002, 224 patients (141 men) with Stage II cancer underwent curative anterior resection or Hartmann's procedure without adjuvant radiation. Data were collected prospectively. The oncologic outcomes of these patients were studied and the risk factors for recurrence and survival were analyzed.

RESULTS

The median age of the patients was 69 (range, 27-89) years and the median level of the tumor from the anal verge was 8 (range, 3-20) cm. Four patients (1.8 percent) died in the postoperative period and postoperative complications occurred in 74 patients (33 percent). The median follow-up time of the surviving patients was 43.6 months. The actuarial five-year recurrence rate was 25.4 percent, whereas the five-year actuarial local and systemic recurrence rates were 6.1 percent and 20 percent, respectively. On multivariate analysis, independent factors associated with a higher recurrence rate included lymphovascular invasion, perineural invasion, and absence of chemotherapy. The overall and cancer-specific survival rates of the patients were 71.1 percent and 81.1 percent, respectively. On multivariate analysis, only adjuvant chemotherapy (P = 0.024; hazard ratio = 6.04; 95 percent confidence interval, 1.27-28.74) and the absence of lymphovascular invasion (P = 0.002; hazard ratio = 3.77; 95 percent confidence interval, 1.63-8.77) were independent factors associated with significantly better cancer-specific survival.

CONCLUSION

A low local recurrence rate can be achieved in patients with Stage II rectal cancer treated with nonsphincter-ablation surgery without adjuvant radiation. Postoperative chemotherapy is associated with a lower recurrence rate and higher survival rates. Further study is warranted to define the role of adjuvant chemotherapy in patients with rectal cancer.

Evacuation of neorectal reservoirs after TME

Colon pouch reconstruction after deep rectal resection is functionally superior to straight colorectal/anal anastomosis. However, stool evacuation difficulties could jeopardize the functional benefit of neorectal reservoirs. Beside the well proven colon J-pouch, the transverse coloplasty pouch may represent a viable alternative. We examined evacuation and functional outcome after total mesorectal excision and transverse coloplasty pouch reconstruction. Thirty consecutive patients with cancer of the middle and distal third of rectum underwent a total mesorectal excision. In all patients, reconstruction was performed with a transverse coloplasty pouch. Pouch and anastomosis were checked by Gastrografin enema postoperatively. Eight months after surgery, video defecography, anal manometry and pouch volumetry were performed and the patients were interviewed according to a standardized continence questionnaire. Rectal resection and reconstruction with transverse coloplasty pouch anastomosis could be performed in all patients. No insufficiency of the pouch occurred. In the follow-up, no patient had difficulties to evacuate the pouch, none of these patients needed enemas or suppositories to facilitate defecation. All patients were continent for solid stools. Twenty-five of 27 patients had up to three bowel movements per day. Patients with reduced pelvic floor movement in the defecography proved more likely to suffer from urgency, fragmented evacuation and incontinence. Transverse coloplasty pouch reconstruction after total mesorectal excision is not associated with stool evacuation problems. Urgency and incontinence, which are rarely seen after this type of reconstruction, correlate with impaired pelvic floor movement rather than with pouch size or anal sphincter tonus.

Abdominoperineal resection is associated with poor oncological outcome

BACKGROUND

The aim of this study was to compare the operative results and oncological outcomes of patients who had mid or distal rectal cancer treated by abdominoperineal resection (APR) with those treated without sphincter ablation (non-APR).

METHODS

Five hundred and four consecutive patients (308 men and 196 women) with rectal cancer within 12 cm from the anal verge underwent radical resection with curative intent. Sharp mesorectal dissection was used. Operative results and long-term outcomes were compared between those treated by APR and those by non-APR.

RESULTS

Sixty-nine patients had APR and 435 patients were treated with radical resection without perineal resection (anterior resection, 419; Hartmann's operation, 16). The overall operative mortality and morbidity rates were 1.6 and 31.0 per cent respectively. Age, sex, duration of surgery, blood loss, duration of hospital stay, operative mortality and overall morbidity were similar in the two groups. Local recurrence was more frequent after curative APR than after non-APR (23 versus 10.2 per cent at 5 years; P = 0.010). Five-year cancer-specific survival rates after APR and non-APR were 60 and 74.0 per cent respectively (P = 0.006). APR was an independent factor for poor cancer-specific survival in multivariate analysis.

CONCLUSION

Although postoperative mortality and morbidity rates were similar in patients with or without sphincter ablation, local control and survival were worse in those treated by APR.

Transverse coloplasty pouch after total mesorectal excision: functional assessment of evacuation

PURPOSE

Colon pouch reconstruction after total mesorectal excision is functionally superior to straight colorectal/ anal anastomosis. In the long-term, stool evacuation difficulties could jeopardize the functional benefit. The transverse coloplasty pouch presents an alternative to the standard J-pouch. This study was designed to analyze functional outcome and defecography findings after total mesorectal excision and transverse coloplasty pouch reconstruction.

METHODS

Thirty consecutive patients with cancer of the middle and lower third of the rectum underwent a total mesorectal excision and were examined in a prospective study. In all patients, reconstruction was performed with a transverse coloplasty pouch. Pouch and anastomosis were checked by Gastrografin enema postoperatively. Patients were examined within eight months by means of defecography, manometry, pouch volumetry, and a standardized continence questionnaire.

RESULTS

Total mesorectal excision with transverse coloplasty pouch anastomosis was performed successfully in all patients. Symptomatic anastomotic leakage was observed in 2 of 30 patients and the radiologic leak rate was 4 of 30. All patients evacuated the pouch completely; none needed enemas or suppositories to facilitate defecation. Twenty-five of 27 patients had a maximum of three bowel movements per day, and all patients were continent for solid stools. Patients with abnormal findings on defecography proved more likely to have anal dysfunction.

CONCLUSIONS

Transverse coloplasty pouch reconstruction after total mesorectal excision leads to good functional results and is not associated with stool evacuation problems. Urgency and incontinence correlate rather with impaired pelvic floor movement than with pouch size or anal sphincter tonus.

Anterior resection for rectal cancer with mesorectal excision: a prospective evaluation of 622 patients

OBJECTIVE

This study aims to review the operative results and oncological outcomes of anterior resection for rectal and rectosigmoid cancer. Comparison was made between patients with total mesorectal excision (TME) for mid and distal cancer and partial mesorectal excision (PME) for proximal cancer, when a 4- to 5-cm mesorectal margin could be achieved. Risk factors for local recurrence and survival were also analyzed.

SUMMARY BACKGROUND DATA

Anterior resection has become the preferred treatment option rectal cancer. TME with sharp dissection has been shown to be associated with a low local recurrence rate. Controversies still exist as to the need for TME in more proximal tumor.

METHODS

Resection of primary rectal and rectosigmoid cancer was performed in 786 patients from August 1993 to July 2002. Of these, 622 patients (395 men and 227 women; median age, 67 years) underwent anterior resection. The technique of perimesorectal dissection was used. Patients with mid and distal rectal cancer were treated with TME while PME was performed for those with more proximal tumors. Prospective data on the postoperative results and oncological outcomes were reviewed. Risk factors for anastomotic leakage, local recurrence, and survival of the patients were analyzed with univariate and multivariate analysis.

RESULTS

The median level of the tumor was 8 cm from the anal verge (range, 2.5-20 cm) and curative resection was performed in 563 patients (90.5%). TME was performed in 396 patients (63.7%). Significantly longer median operating time, more blood loss, and a longer hospital stay were found in patients with TME. The overall operative mortality and morbidity rates were 1.8% and 32.6%, respectively, and there were no significant differences between those of TME and PME. Anastomotic leak occurred in 8.1% and 1.3% of patients with TME and PME, respectively (P < 0.001). Independent factors for a higher anastomotic leakage rate were TME, the male gender, the absence of stoma, and the increased blood loss. The 5-year actuarial local recurrence rate was 9.7%. The advanced stage of the disease and the performance of coloanal anastomosis were independent factors for increased local recurrence. The 5-year cancer-specific survival was 74.5%. The independent factors for poor survival were the advanced stage of the disease and the presence of lymphovascular and perineural invasion.

CONCLUSIONS

Anterior resection with mesorectal excision is a safe option and can be performed in the majority of patients with rectal cancer. The local recurrence rate was 9.7% and the cancer-specific survival was 74.5%. When the tumor requires a TME, this procedure is more complex and has a higher leakage rate than in those higher tumors where PME provides adequate mesorectal clearance. By performing TME in patients with mid and distal rectal cancer, the local control and survival of these patients are similar to those of patients with proximal cancers where adequate clearance can be achieved by PME.

Sphincter-saving surgery for low rectal cancer. The experience of the National Cancer Institute, Milano

The treatment of tumors of the distal rectum continues to be a matter of great controversy among oncologic surgeons. There are increasingly promising indications that functionally conservative surgery may be a valid therapeutic alternative to conventional therapy in patients with tumours of the lower rectum, traditionally treated by abdomino-perineal resection and definitive colostomy. Many points are presently under evaluation and we want to discuss some of the most relevant topics that are now permitting to change the guide lines of therapy of this disease. Our view of the problem is based on a personal experience cumulated in fourteen years of activity in a specialized unit and this paper reports the main results of a complex and diversified study carried out during this period at the National Cancer Institute of Milan.

Quality assurance of surgery in gastric and rectal cancer

Multimodality and quality controlled treatment result in improved treatment outcome in patients with solid tumours. Quality assurance focuses on identifying and reducing variations in treatment strategy. Treatment outcome is subsequently improved through the introduction of programs that reduce treatment variations to an acceptable level and implement standardised treatment. In chemotherapy and radiotherapy, such programmes have been introduced successfully. In surgery however, there has been little attention for quality assurance so far. Surgery is the mainstay in the treatment of patients with gastric and rectal cancer. In gastric cancer, the extent of surgery is continuously being debated. In Japan, extended lymph node dissection is favoured whereas in the West this type of surgery is not routinely performed with two large European trials concluding that there is no survival benefit from regional lymph node clearance. Post-operative chemoradiation is part of the standard treatment in the United States, although its role in combination with adequate surgery has not been established yet. These global differences in treatment policy clearly relate to the extent and quality of surgical treatment. As for gastric cancer, surgical treatment of rectal cancer patients determines patient's prognosis to a large extent. With the introduction of total mesorectal excision, local control and survival have improved substantially. Most rectal cancer patients receive adjuvant treatment, either pre- or post-operatively. The efficacy of many adjuvant treatment regimens has been investigated in combination with conventional suboptimal surgery. Traditional indications of adjuvant treatment might have to be re-examined, considering the substantial changes in surgical practise. Quality assurance programs enable the introduction of standardised and quality controlled surgery. Promising adjuvant regimens should be investigated in combination with optimal surgery.

Estimation of an optimal radiotherapy utilization rate for gastrointestinal carcinoma

BACKGROUND

Radiotherapy utilization rates for cancer vary widely, both within and between countries. The optimal proportion of patients with gastrointestinal malignancies who should receive at least one course of radiotherapy at some time during their illness is an important benchmark.

METHODS

The authors studied treatment guidelines and treatment reviews to identify the indications for radiotherapy for patients with gastrointestinal malignancies. Optimal radiotherapy utilization trees were constructed to show the clinical attributes of patients with gastrointestinal carcinomas who will benefit from radiotherapy. Epidemiologic incidence data for each of these clinical attributes were obtained to calculate the optimal proportion of all patients with gastrointestinal malignancies for whom radiotherapy was considered appropriate. Optimal rates of radiotherapy use were compared with actual rates in population-based studies to assess any discrepancies between actual and optimal radiotherapy utilization rates.

RESULTS

Radiotherapy was indicated in 80% of patients with esophageal carcinoma, 68% of patients with gastric carcinoma, 57% of patients with pancreatic carcinoma, 13% of patients with carcinoma of the gallbladder, 0% of patients with hepatic carcinoma, 14% of patients with colon carcinoma, and 61% of patients with rectal carcinoma. The actual radiotherapy utilization rates for most of these gastrointestinal malignancies fell well short of optimal rates, which were derived from evidence-based treatment guidelines.

CONCLUSIONS

It is possible to model optimal radiotherapy utilization using published treatment guidelines and existing incidence data. There was a discrepancy between the optimal and actual rates of radiotherapy utilization for patients with carcinomas of the esophagus, stomach, pancreas, and rectum. Strategies to implement evidence-based clinical guidelines are recommended.

Sphincter saving rectum resection is the standard procedure for low rectal cancer

AIM

To determine the procedure of choice for rectal cancer, particularly low rectal cancer.

METHODS

Complete search, according to evidence-based methods, of comparative studies and national surveys published in English since 1990.

SELECTION CRITERIA

comparative studies between abdominoperineal excision (APER) and sphincter-saving operations (SSO) with a minimum of 50 patients presenting cancer in the lower one-third of the rectum, perfect split of cases with cancer located in the lower, middle or upper one-thirds of the rectum, specified numbers of patients treated by surgery alone or combined with radio-chemotherapy, specified length of follow-up with a minimum of 1 year, univariate or multivariate analysis of prognostic factors. Thirty-four studies fulfilling evidence level C were analyzed, including 6,570 patients.

ENDPOINTS

operative risk, local disease control, disease free or cancer specific survival and quality of life.

RESULTS

Postoperative morbidity after APER and SSO is comparable and postoperative mortality decreased to 2% or less. The type of surgery was not identified as a prognostic factor in terms of local disease control and survival. Quality of life is significantly inferior after APER. National data reveal an APER rate for cancer of the whole rectum (up to 16 cm) at 50% or above, and SSO still would represent only 32% of the radical resections for low rectal cancer.

CONCLUSION

All available evidence indicates that SSO should be the procedure of choice for rectal cancer, even in the lower one-third. An APER should only be performed when cancer invades the anal sphincters and negative resection margins cannot be achieved by a SSO.

An evidence-based estimate of the appropriate radiotherapy utilization rate for colorectal cancer

PURPOSE

Current estimates of the proportion of cancer patients who will require RT are based almost entirely on expert opinion. The objective of this study was to estimate the proportion of incident cases of colorectal cancer that should receive RT using an evidence-based approach.

METHODS AND MATERIALS

A systematic review of the literature was undertaken to identify indications for RT for colorectal cancer, and to ascertain the level of evidence that supported each indication. An epidemiologic approach was then used to estimate the incidence of each indication for RT in a typical North American population of colorectal cancer patients. The effect of sampling error on the estimated appropriate rate of RT was calculated mathematically, and the effect of systematic error was estimated by sensitivity analysis.

RESULTS

It was estimated that 23.7% +/- 1.0% of colorectal cancer cases develop one or more indications for RT at some point in the course of the illness: 20.9% +/- 1.1% as part of their initial treatment, and 2.8% +/- 0.5% later for recurrence or progression. We estimated that 7.1% +/- 0.8% of colon carcinoma patients will require RT at some point in the course of the illness: 4.0% +/- 0.7% as part of their initial treatment, and 3.1% +/- 0.4% later for recurrence or progression. We estimated that 72.3% +/- 1.0% of rectal carcinoma patients will require RT at some point in the course of the illness: 69.6% +/- 0.9% as part of their initial treatment and 2.7% +/- 0.2% later for recurrence or progression.

CONCLUSIONS

This method provides a rational starting point for the long-term planning of radiation services, and for the audit of access to RT at the population level. By completing such evaluations in the major cancer sites, it will be possible to estimate the appropriate RT treatment rate for the cancer population as a whole.

The role of total mesorectal excision in the management of rectal cancer

During the past decade, it has been clearly demonstrated that adjuvant treatment has the potential of improving not only prognosis in terms of local recurrence, but also in terms of overall survival. However, one of the largest improvements in the outcome of rectal cancer has been the introduction of total mesorectal excision. TME, with its large decline in local recurrence rate, has become the new standard of operative management for rectal cancers, replacing conventional resection technique [68]. In addition, current clinical trials examining the role of adjuvant therapy in patients who are undergoing standardized operations are now setting the standard of surgical care in several countries.

Strategies in the management of mid and distal rectal cancer with total mesorectal excision

In the last two decades, dramatic improvement in outcome has been made in the management of rectal cancer. This has been brought about mainly by advancements in surgical technique for radical resection. With the recognition of the importance of the circumferential margin and presence of spread in the lymphovascular tissues in the mesorectum, total mesorectal excision is now commonly recognized as the optimal surgical technique for cancer of the mid and distal rectum. Not only have local control and disease-specific survival improved with the practice of total mesorectal excision, but various bodily functions have also been preserved following surgery for rectal cancer. New issues have arisen with the practice of total mesorectal excision and the strategies for management of rectal cancer require re-evaluation. In this article, the rationale and the outcomes of total mesorectal excision are reviewed. Issues such as the high anastomotic leakage rate following sphincter-preserving surgery, the poor results of abdominoperineal resection, the role of adjuvant therapy and bowel function disturbances will be addressed. Lastly, the status of the laparoscopic approach to rectal cancer with the principle of total mesorectal excision are discussed.

Developments and quality assurance in rectal cancer surgery

One of the main problems in the treatment of rectal cancer is the development of local recurrences. In the last decades, major improvements have been realized in the surgical treatment of rectal cancer. The introduction of TME-surgery has led to a large reduction in local recurrence rates and improved survival. TME-based operations are now established as the standard of care for rectal cancer, and should form the basis for trials concerning the role of (neo)adjuvant therapy. However, training and quality control are prerequisites to obtain good results in all surgeons' hands. Furthermore, standardization in the description of operations and reporting of pathology specimens should be implemented as important features of quality control. In general, it is thought that high volume and specialist care produces superior results to low volume and non-specialist care, especially for those less frequent forms of cancer and in technically difficult operations, like those for rectal cancer. However, limiting the performance of rectal cancer surgery to highly specialized surgeons or to only those general surgeons who perform more than a certain volume is impractical in view of the prevalence of rectal cancer. This article reviews developments in the treatment of especially mobile rectal cancer and pays attention to variability in outcomes and quality assurance of surgery.

Impact of total mesorectal excision on the results of surgery of distal rectal cancer

BACKGROUND

This study reviewed the results of surgery for distal rectal cancer (tumours within 6 cm of the anal verge) following the introduction of total mesorectal excision for rectal cancer in one institution.

METHODS

Two hundred and five patients who had undergone surgical resection of rectal cancer within 6 cm of the anal verge were included. The demographic, operative and follow-up data were collected prospectively. Comparisons were made between patients who had different surgical procedures.

RESULTS

Abdominoperineal resection (APR) was performed in 27.8 per cent of patients, falling from 36.0 per cent in the first 3 years to 20.0 per cent in the last 3 years of the study. The overall operative mortality rate was 1.5 per cent and the morbidity rate 30.2 per cent. With a mean follow-up of 36 months, local recurrence occurred in 28 of the 185 patients who had curative resection. The 5-year actuarial local recurrence rates for double-stapled anastomosis, peranal coloanal anastomosis and APR were 11.2, 34.6 and 23.5 per cent respectively. The local recurrence rate was significantly lower for double-stapled low anterior resection than for the other types of operation. The overall 5-year survival rate in patients with low anterior resection and APR was 69.1 and 51.1 per cent respectively (P = 0.12).

CONCLUSION

With the practice of total mesorectal excision, APR was necessary in only 27.8 per cent of patients with rectal cancer within 6 cm of the anal verge. The local recurrence rate was much lower in patients with double-stapled low anterior resection than in those treated with APR or peranal anastomosis.

Methodology and reporting in studies of local recurrence after curative excision of the rectum for cancer

BACKGROUND

Widely varying rates have been reported in the extensive literature published in the English language on local recurrence after curative excision of rectal carcinoma. These variations may be attributable to differences in the case mix of pathological factors influencing recurrence, differences in surgical technique or expertise, differences in the administration of adjuvant therapy and various combinations of these. They may also arise from methodological differences among studies.

METHODS

This paper reviews the adequacy of methodology and reporting in 21 recent studies of local recurrence after curative resection of rectal cancer.

RESULTS

Many flaws in reporting and apparent inadequacies in methodology were identified. On an index of 26 criteria examined, eight studies scored no more than 8 and only three studies scored more than 11.

CONCLUSION

To date, the value of reports of local recurrence rates following curative excision of rectal cancer has been limited by inadequacies in documentation and methodology. Suggestions are made for preferred procedures to be followed in the reporting of future studies.

Local excision of T2 and T3 rectal cancers after downstaging chemoradiation

OBJECTIVE

To evaluate the safety and efficacy of local excision in patients with T2 and T3 distal rectal cancers that have been downstaged by preoperative chemoradiation.

SUMMARY BACKGROUND DATA

T2 and T3 cancers treated by local excision alone are associated with unacceptably high recurrence rates. The authors hypothesized that preoperative chemoradiation might downstage both T2 and T3 lesions and significantly expand the indications for local excision.

METHODS

Local excision was performed after preoperative chemoradiation on patients with a complete clinical response or on patients who were either ineligible for or refused to undergo abdominoperineal resection. Local excision was approached transanally by removing full-thickness rectal wall and the underlying mesorectum.

RESULTS

From 1994 to 2000, 95 patients with rectal cancers underwent preoperative chemoradiation and surgical resection for curative intent. Of these, 26 patients (28%), 19 men and 7 women, with a mean age of 63 years (range 44-90), underwent local excision. Pretreatment endoscopic ultrasound classifications included 5 T2N0, 13 T3N0, 7 T3N1, and 1 not done. Pathologic partial and complete responses were achieved in 9 of 26 (35%) and 17 of 26 (65%) patients, respectively. Two of nine partial responders underwent immediate abdominoperineal resection. The mean follow-up was 24 months (median 19, range 6-77). The only recurrence was in a patient who refused to undergo abdominoperineal resection after a partial response. There was one postoperative death from a stroke. This treatment was associated with a low rate of complications.

CONCLUSION

Local excision appears to be an effective alternative treatment to radical surgical resection for a highly select subset of patients with T2 and T3 adenocarcinomas of the distal rectum who show a complete pathologic response to preoperative chemoradiation.

Locally recurrent rectal cancer: role of composite resection of extensive pelvic tumors with strategies for minimizing risk of recurrence

Locally recurrent cancer of the rectum has been under-recognized as a complication, although it affects up to 40% of patients treated with surgery alone. Even in the best centers, rates average 25%. While radiotherapy may reduce recurrence, it is now apparent that total mesorectal excision is the most effective modality, with rates as low as 5%. The dramatic decrease in local recurrence can also be linked to increased survival in prospective studies, an effect more significant than any adjuvant therapy. The options, however, for patients with locally recurrent cancer are limited. Fifteen percent of patients with this complication die without systemic spread. Salvage by surgery offers potential cure. Other than anastomotic recurrences that can be locally resected, the best approach for long-term survival is an extensive surgical procedure requiring en bloc removal of adjacent organs and pelvic structures-so-called composite resection. With careful selection, 30% 5-year survival can be achieved and palliation is considerable, with 50% long-term local control. Intraoperative radiotherapy and brachytherapy, and/or preoperative chemoradiation may provide better results in future. Newer techniques of coloanal anastomosis, improved urinary diversion, and myocutaneous flaps for perineal reconstruction radically reduce the morbidity of these procedures. The approach to recurrent rectal cancer requires a sophisticated multidisciplinary team to obtain optimum results.

Is intensive follow-up really able to improve prognosis of patients with local recurrence after curative surgery for rectal cancer?

BACKGROUND

Because more than 90% of local recurrences after curative surgery for rectal cancer appear within the first 36 months after surgery, an intensive and strict follow-up program during this period could improve early diagnosis and, thus, prognosis of patients.

METHODS

Of the 216 patients who underwent surgery for rectal cancer, 127 entered an intensive follow-up program (median follow-up: 42 months); the clinical outcome of the remaining 89 patients was reconstructed with the help of their general practitioners.

RESULTS

Fifty eight (26.8%) of the 216 patients who were treated with curative surgery alone developed a local recurrence; pelvic recurrences were prevalent. Eleven (30.5%) of the 36 patients who had recurrence during follow-up, and 6 of the 22 who had not undergone follow-up, had a reoperation with curative intent; the median survival was 19 months vs. 8 months, respectively (P = ns). Four (44.4%) curative reoperations were performed on the 9 asymptomatic patients and in 13 (26.5%) of the 49 cases with symptomatic local recurrences. Median survival was 15 months vs. 14 months, respectively (P = n.s). All patients except one (living after 42 months from reoperation) died within 48 months.

CONCLUSIONS

In our study, adherence to a strict follow-up program unfortunately proved to be ineffective for improving long-term survival for patients who underwent reoperation with curative intent.

Chemoradiation with or without intraoperative radiation therapy in patients with locally recurrent rectal carcinoma: prognostic factors and long term outcome

BACKGROUND

Rectal carcinoma patients with local recurrence are reported to have a dismal prognosis. The purpose of this study was to evaluate the effect of combined modality therapy on clinical outcome and to determine the prognostic impact of a "presurgical" staging system.

METHODS

Between September 1989 and June 1997, 47 patients (with a median follow-up of 80 months) with locally recurrent, nonmetastatic rectal carcinoma were classified according to the extent of pelvic sidewall involvement as determined by pretreatment computed tomography (CT) scan. They received preoperative external beam radiation (45-47 grays [Gy] in 34 patients; 23.4 Gy in 13 preirradiated patients) plus concomitant 5-fluorouracil (1000 mg/m(2)/day as a 96-hour continuous infusion on Days 1-4 + 29-32) and mitomycin C (10 mg/m(2) as a bolus intravenously on Day 1 + 29). After 4-6 weeks, the patients were evaluated for surgical resection and intraoperative radiation therapy (IORT) procedure (10-15 Gy) or, in unresectable patients, a boost dose was planned by chemoradiation (23.4 Gy) or brachytherapy. Thereafter, adjuvant chemotherapy (5-fluorouracil and leucovorin for a total of six to nine courses) was prescribed.

RESULTS

During chemoradiation, 2 patients (4.3%) developed Radiation Therapy Oncology Group Grade 3-4 acute toxicity. Twenty-five patients (53. 2%) had an objective response after chemoradiation. Twenty-one patients (45%) underwent radical surgical resection. The overall 5-year survival and local control rates were 22% and 32%, respectively. The classification system significantly predicted survival (P = 0.008). Radically resected patients had better local control and survival (P < 0.0001); in patients treated with IORT, the 5-year local control and survival rates were 79% and 41%, respectively.

CONCLUSIONS

The data from the current study suggest that combined modality therapy was well tolerated and improved resectability, local control, and survival. The classification system appears to be a reliable tool with which to predict clinical outcome in patients with locally recurrent rectal carcinoma.

Multidisciplinary management of recurrent colorectal cancer

Isolated pelvic recurrence of rectal carcinoma may occur in up to one third of patients following definitive resection of primary disease. The means by which recurrence is diagnosed, methods by which it may be treated, and reported outcomes are all evolving and improving. Current data indicate that a substantial proportion of patients treated by aggressive multi-modality salvage therapy may be provided with durable survival. This review highlights current concepts in the diagnosis and management of locally recurrent rectal carcinoma.

Mesorectal excision for rectal cancer: a view from Europe

The local recurrence rate after rectal cancer surgery is discussed as related to conventional and total mesorectal excision (TME) techniques. Studies now show that the wide variation in results between centers and among surgeons depends, at least in part, on differences in surgical technique. We conclude that local tumor recurrence rate is lower after TME than after conventional surgery and emphasize the importance of a standardized macroscopic evaluation of the resected specimen. Population-based registration to evaluate the quality of surgery is recommended. It is also suggested that randomized studies on adjuvant treatment for rectal cancer should include a "surgery only" arm when a local tumor recurrence rate of 10% or less is being studied. Until such investigations are performed, we conclude that the role for adjuvant treatment is questionable and that TME surgery is preferred as the treatment option for Stage T1-T3 rectal cancers.

Radiation Therapy for Local-Regional Recurrences of Rectal Carcinoma following Primary Surgery

Aims and background

Several studies have emphasized the role of radiation therapy for patients with pelvic recurrences of rectal carcinoma following primary surgery. The occurrence of local-regional relapse usually means a poor prognosis and often a poor quality of life, so that different authors consider the prognosis of patients relapsing after surgery worse than those with primary inoperable tumors or those with residual disease after resection.

Methods

Between January 1988 and January 1995, 43 patients with local recurrence of rectal carcinoma were treated at our Institution. Twenty-three had previously been operated by abdominoperineal resection and 20 by anterior resection. Thirteen cases also received adjuvant chemotherapy. All patients underwent irradiation with a 6-15 MeV linear accelerator; 8 (19%) received a total dose of up to 45 Gy on the pelvis and 35 (81%) higher than 45 Gy. Eighteen cases (42%) underwent 3-6 courses of chemotherapy with 5-fluorouracil and folates during radiation.

Results

Treatment tolerance was satisfactory. All cases underwent restaging at 45 days from completion of treatment. Sixteen cases (37%) showed a radiologic response >50%. Median overall survival after relapse was 18.8 months. There were no statistical significant differences in survival between patients treated exclusively with radiation and those treated with chemo-radiothera-py (17 vs 22 months). The results of patients who received doses higher than 45 Gy were statically better (P < 0.05) than those irradiated up to 45 Gy. A slight increase in survival was demonstrated in cases submitted to radical surgery after combined treatment (25 months). Twenty-seven cases (63%) obtained pain control after radiation therapy (median pain remission, 11 months).

Conclusions

Our results seem to encourage radiation therapists, surgeons and oncologists to have a more curative attitude in the treatment of selected patients with local-regional recurrences of rectal cancers by using multi-modality therapy.

Total anorectal reconstruction with a double dynamic graciloplasty after abdominoperineal reconstruction for low rectal cancer

PURPOSE

Total anorectal reconstruction with a double dynamic graciloplasty was performed after abdominoperineal reconstruction (APR) for low rectal cancer. In four patients an additional pouch was constructed to improve neorectal motility and capacity. The aim of this study was to evaluate the results in the first 20 patients and to report on the preliminary results of patients with an additional pouch.

METHODS

Twenty patients with a mean age of 52 (range, 25-71) years and a rectal tumor at a mean of 3 (range, 0-5) cm from the anal verge were treated. In 14 patients the Miles resection, colon pull-through, and construction of a neosphincter were performed in one session. Six patients had the double graciloplasty at an average of 4.1 (range, 1.1-8.8) years after APR. In four patients a pouch was constructed with an isolated segment of distal ileum.

RESULTS

After a mean follow-up of 24 (range, 1-60) months after APR, none of the patients developed local recurrence, whereas four patients developed distant metastasis. Fifteen of 20 patients were available for evaluation, and 5 patients were still in training. Of these 15 patients, 8 patients were continent (53 percent), 2 patients were incontinent, and in 5 patients the perineal stoma was converted to an abdominal stoma. Failures were attributable to necrosis of the colon stump (n = 2) and incontinence (n = 3). At 26 weeks mean resting pressure was 44 (standard deviation (SD), 28) mmHg, and mean pressure during stimulation was 90 (SD, 46) mmHg at a mean of 3.5 (SD, 1.2) volts at 52 weeks. Mean defecation frequency was three times per day (range, 1-5). Of the eight patients who were continent, six used daily enemas. Mean time to postpone defecation was 11 (range, 0-30) minutes.

CONCLUSION

In experienced hands, the double dynamic graciloplasty is an oncologically safe procedure that can have an acceptable functional outcome in a well-selected group of patients. However, to improve the outcome, further modifications will be necessary. So far, the addition of a pouch has not resulted in improved outcome.

Preservation of the anus in the therapy of distal rectal cancers

Using the gold standard of APR as a measure of cancer control, sphincter-sparing procedures appear to provide similar rates of local control and survival. Specifically, for T1, T2, and T3 lesions, local excision alone, local excision plus adjuvant therapy, and low anterior resection with coloanal anastomoses, respectively, have proven to be acceptable forms of therapy. However, questions remain as to the significance of certain prognostic factors, such as lymphatic invasion with regard to the treatment plan for patients with low rectal cancers. Lastly, quantitative studies addressing the issue of the function of the spared anal sphincters after surgery with or without adjuvant therapy, and how this relates to the patient's quality of life, need to be performed.

Evaluation and biopsy of recurrent rectal cancer using three-dimensional endosonography

PURPOSE

The value of endorectal ultrasonography for postoperative follow-up of rectal cancer is limited by the inability to distinguish recurrent malignancy from benign lesions, e.g., fibrotic tissue. This study was conducted to investigate the role of three-dimensional (3D) endosonography for evaluation and biopsy of recurrent rectal cancer.

METHODS

Endorectal ultrasonography was performed in routine follow-up program after resection of rectal cancer. 3D volume scans were recorded using a bifocal multiplane 3D transducer (7.5/10 MHz) with a 100 degrees longitudinal and a 360 degrees transversal scan angle. For transrectal ultrasound-guided biopsy of pararectal lesions, a specially designed targeting device was attached to the endoprobe.

RESULTS

Overall pararectal lesions were detected in 28 of 163 patients (17 percent) who were undergoing endorectal ultrasonography for follow-up after resection of rectal cancer. 3D image analysis facilitated assessment of suspicious pararectal lesions by contemporary display of three perpendicular scan planes or volume reconstructions of the scanned area. Ultrasound-guided biopsy was performed in all 28 patients with pararectal lesions identified by endorectal ultrasonography. Biopsy revealed recurrent disease or lymph node metastases in seven and two patients, respectively. Benign lesions explained the endosonographic findings in 17 patients. All patients with benign histology still have no evidence of recurrent disease after a median follow-up of seven months. Nonrepresentative material was obtained in only 2 of 28 patients (accuracy, 93 percent). Histology changed the endosonographic diagnosis in 28 percent of cases.

CONCLUSIONS

3D endosonography with ultrasound-guided biopsy improves the diagnosis of extramural recurrence after curative resection of rectal cancer. 3D image display allows precise control of the position of the biopsy needle within the target.