Evaluation of a pre-operative staging protocol in the management of colorectal carcinoma

Indeterminate pulmonary nodules at colorectal cancer staging: a systematic review of predictive parameters for malignancy

BACKGROUND

This study aimed to estimate the prevalence of indeterminate pulmonary nodules and specific radiological and clinical characteristics that predict malignancy of these at initial staging chest computed tomography (CT) in patients with colorectal cancer. A considerable number of indeterminate pulmonary nodules, which cannot readily be classified as either benign or malignant, are detected at initial staging chest CT in colorectal cancer patients.

METHODS

A systematic review based on a search in EMBASE, Medline, the Cochrane library and science citation index, PubMed databases, Google scholar, and relevant conference proceedings was performed in cooperation with the Cochrane Colorectal Cancer Group.

RESULTS

A total of 2,799 studies were identified, of which 12 studies met the inclusion criteria. The studies primarily consisted of case series and included a total of 5,873 patients. Of these patients, 9% (95% confidence interval [95% CI] 8.9-9.2%) had indeterminate pulmonary nodules at chest CT, of which 10.8% (95% CI 10.3-11.2%) turned out to be colorectal cancer metastases at follow-up. Generally, regional lymph node metastasis, and multiple numbers of indeterminate pulmonary nodules were reported to predict malignancy, whereas calcification of the nodules indicated benign lesions.

CONCLUSION

It was found that 1 in 100 colorectal cancer patients subjected to preoperative staging chest CT will have an indeterminate pulmonary nodule that proves to be metastatic disease. Such a low risk suggests that indeterminate pulmonary nodules should not cause further preoperative diagnostic workup or follow-up besides routine regimens.

A comparative study of colorectal surgical outcome in a national audit separated by 15 years

AIM

The Wales-Trent Bowel Cancer Audit (WTBA) was carried out in 1993, and since 2001 Welsh Bowel Cancer Audits (WBCA) have taken place annually. Screening for bowel cancer in Wales was introduced in 2008. This study compared patient variables, the role of surgery and operative mortality rates over the 15-year interval between the WTBA and the last WBCA before the introduction of population screening.

METHOD

Data from the WTBA in 1993 were compared with those of the WBCA including patients diagnosed between April 2007 and March 2008.

RESULTS

In 1993, 1536 patients were diagnosed with colorectal cancer (CRC) compared with 1793 in 2007-2008. Patient demographics and American Society of Anesthesiology (ASA) score did not change during these periods. Surgical treatment for CRC decreased (93% in 1993 vs 80% in 2007-2008; P < 0.001) particularly in the use of resectional surgery (84% in 1993 vs 71% in 2007-2008; P < 0.001). The 30-day postoperative mortality rate fell from 7.4% in 1993 to 5.9% in 2007-2008 (P = 0.097). Advanced disease at operation was more prevalent in the WTBA (25% of all operated patients were Stage IV in 1993 vs 13% in 2007-2008; P < 0.001). The use of surgery in patients with metastatic disease also declined over this period.

CONCLUSION

Surgery is used less frequently in the management of CRC compared with 15 years previously, and is a factor in the reduction of the interpreted 30-day operative mortality.

Pulmonary staging in colorectal cancer: a review

AIM

Assessment of the chest in colorectal cancer (CRC) staging is variable. The aim of this review was to look at different chest staging strategies and determine which has the greatest efficacy.

METHOD

A review of studies assessing chest staging modalities for patients with CRC was performed. Modalities included chest X-ray (CXR), CT and positron emission tomography (PET).

RESULTS

The majority of data consisted of case series. Two studies identified a low pick-up rate for CXR as a staging tool. Five studies showed increased detection rates of pulmonary metastases for chest CT vs CXR and abdominal CT. The clinical benefit of the increased detection rates was not clear. The incidence of indeterminate lung lesions (ILL) on staging chest CT varied from 4 to 42%. The majority (≥ 70%) of ILLs did not have any clinical significance. On CT scans, the incidence of pulmonary metastases in patients with rectal cancer ranged from 10 to 18% and in patients with colon cancer the incidence of pulmonary metastases ranged from 5-6%. The incidence of synchronous liver and pulmonary metastases compared with the overall incidence of pulmonary metastases ranged from 45 to 70%. There was no evidence reporting the superiority of PET/CT vs CT for the detection of pulmonary metastases or characterization of ILL.

CONCLUSION

Studies show that chest CT scanning increases the detection rates for ILL and pulmonary metastases. The clinical benefit of the increased detection rates is not clear. There is a paucity of data assessing the optimal chest staging strategy for patients presenting with CRC.

Recurrences after local excision for early rectal adenocarcinoma

PURPOSE

The role of local excision in treating rectal cancer patients continues to be controversial. The aim of this study was to evaluate the long-term oncological results of local excision for early rectal adenocarcinomas and review the outcomes of salvage therapy on rectal cancer patients.

MATERIALS AND METHODS

Between March 1992 and September 2005, 35 consecutive patients with early-stage primary rectal adenocarcinomas were treated by local excision with curative intent. The mean tumor distance from the anal verge was 5 cm (range, 1-10 cm).

RESULTS

The median follow-up was 66 months (range, 17-161 months). Pathological examination revealed 23 cases of T1 and 12 cases of T2. Recurrence had developed in 10 patients (6 local recurrences, 4 systemic recurrences). Purely extrapelvic recurrence was observed in only two (5.7%) patients. Of the eight recurrent patients with surgical salvage, five survived with no evidence of disease at the time of this analysis. The 5-year local recurrence-free and disease-free survival rates were 79.6% and 67.9%, respectively.

CONCLUSION

Local excision alone of early-staged rectal adenocarcinomas, even in the ideal candidate, is followed by a relatively higher local recurrence rate than previously reported and may not be a valid modality. Either the use of adjuvant therapy with local excision, even in patients with T1 lesions or the use of preoperative therapy followed by local excision has good promise.

Staging chest radiography is not useful in patients with colorectal cancer

INTRODUCTION

International guidelines recommend a staging chest X-ray (SCXR) in patients with colorectal cancer to exclude pulmonary metastases. The SCXR is controversial, because evidence to support its use is insufficient. The aim of this study was to determine the value of the SCXR in patients with colorectal cancer.

PATIENTS AND METHODS

Between January 1992 and August 2006, data from all patients with colorectal cancer, who presented to the surgical clinic of the Maasland Hospital, were prospectively collected and analysed. The main outcome was the rate of pulmonary metastases on SCXR. The secondary outcome was the influence of SCXR on patient management.

RESULTS

Out of 1410 patients, 1057 had a chest X-ray before their operation. Median follow-up time was 4 years and 6 months (25th percentile 1 year and 7 months, 75th percentile 6 years and 11 months). Eight patients were excluded because follow-up data were incomplete. In 24 patients the chest X-ray was suggestive of malignancy; 9 of these patients actually had pulmonary metastases. Patient management was changed in 5 of them. Four patients were identified to have primary lung cancer. These data indicate a 0.86% detection rate of pulmonary metastases (confidence interval, 0.3-1.4%).

DISCUSSION

Our results show that SCXR has a low detection rate of pulmonary metastases and a small influence on patient management. In accordance with previous studies our data do not support the routine use of the SCXR in patients with colorectal cancer.

Improvable quality of diagnostic assessment of colorectal cancer in southern Netherlands

OBJECTIVE

To determine the extent of guideline implementation of the diagnostic approach in patients with colorectal cancer (CRC) in southern Netherlands in 2005, with special focus on colonoscopy.

METHODS

Data were extracted from the medical records for a random sample of 257 colon and 251 rectal cancer patients newly diagnosed in 2005 and recorded from the Eindhoven Cancer Registry. Adherence to guidelines was determined for diagnostic assessment. Multivariable logistic regression analysis was conducted to assess determinants of complete colonoscopy.

RESULTS

Diagnostic assessment was carried out mainly by internists (50%) and gastroenterologists (36%). Colonoscopy was performed in 83% of patients with proximal/transverse colon cancer, 55% of those with distal colon cancer, and 65% of those with rectal cancer. A tumour biopsy was taken for 84% of colon and 93% of rectal tumours. Colonoscopy completeness was lower for patients with comorbidity, obstructing tumours, and patients with poor bowel preparation. Abdominal ultrasound was performed for 72% of colon and 52% of rectal cancer patients and a thoracic radiography of over 80% of CRC patients. Computed tomography (CT) of the abdomen was performed in over half of the colon cancer patients and a pelvic CT scan or magnetic resonance imaging in 36% of rectal cancer patients.

CONCLUSION

Improvements in adherence to diagnostic guidelines for CRC appear possible, especially in the performance of imaging procedures. Among patients where complete visualization of the colon was not feasible with colonoscopy, imaging techniques such as virtual CT might be of added value in the near future.

Real time contrast enhanced ultrasonography in detection of liver metastases from gastrointestinal cancer

Background

Contrast enhanced ultrasound (CEUS) is an imaging technique which appeared on the market around the year 2000 and proposed for the detection of liver metastases in gastrointestinal cancer patients, a setting in which accurate staging plays a significant role in the choice of treatment.

Methods

A total of 109 patients with colorectal (n = 92) or gastric cancer prospectively underwent computed tomography (CT) scan and conventional US evaluation followed by real time CEUS. A diagnosis of metastases was made by CT or, for lesions not visibile at CT, the diagnosis was achieved by histopathology or by a malignant behavior during follow-up.

Results

Of 109 patients, 65 were found to have metastases at presentation. CEUS improved sensitivity in metastatic livers from 76.9% of patients (US) to 95.4% (p <0.01), while CT scan reached 90.8% (p = n.s. vs CEUS, p < 0.01 vs US). CEUS and CT were more sensitive than US also for detection of single lesions (87 with US, 122 with CEUS, 113 with CT). In 15 patients (13.8%), CEUS revealed more metastases than CT, while CT revealed more metastases than CEUS in 9 patients (8.2%) (p = n.s.).

Conclusion

CEUS is more sensitive than conventional US in the detection of liver metastases and could be usefully employed in the staging of patients with gastrointestinal cancer. Findings at CEUS and CT appear to be complementary in achieving maximum sensitivity.

Effect of using endorectal coil in preoperative staging of rectal carcinomas by pelvic MR imaging

PURPOSE

To assess the accuracy of magnetic resonance imaging with pelvic phased-array and endorectal coils prospectively, and evaluate if endorectal coil provides any additional information to high resolution pelvic MR imaging in rectal carcinoma staging.

MATERIALS AND METHODS

Preoperative MRI of 25 patients with rectal carcinoma was performed with pelvic phased-array coil alone, and with both phased-array coil and endorectal coil placed. Staging was made by evaluating images obtained by using both coils prospectively, and correlated with histopathologic staging. The images were then assessed separately, and compared to each other retrospectively.

RESULTS

Two and 3 of the 5 histopathologically proved T1 tumors were staged correctly on MRI with pelvic phased-array coil alone and after the endorectal coil placement, respectively. Histopathologically identified five T2 tumors were staged correctly as T2 in 4 of the cases, 1 was understaged and 10 of 14 patients who had T3 tumor were staged as T3, 4 of them were understaged as T2 on both techniques. Specificity, sensitivity and accuracy rates for staging of T3 tumors were found as 71%, 100% and 84%, respectively, for each technique. Sensitivity and positive predictive value of N staging were both 88% on both techniques.

CONCLUSION

Pelvic MR imaging after the placement of endorectal coil in addition to the phase-array coil was not superior to the imaging with phased-array coil alone in T staging of rectal carcinomas and the latter achieved better visualization of the lymph nodes by means of larger field of view.

Rectal Cancer

PURPOSE

The aim of the study was to evaluate the incidence of pulmonary metastases detected on thoracic computed tomography in patients with rectal cancer and assess the association between the incidence of pulmonary metastases and the stage of the rectal tumor.

MATERIALS AND METHODS

Fifty-six consecutive patients who were diagnosed with rectal cancer over a 22-month period were included in the study. These patients had local tumor staging with a pelvic magnetic resonance imaging and staging computed tomographic scan of the chest and upper abdomen immediately after the magnetic resonance imaging. Two radiologists retrospectively reviewed all the thoracic imaging performed on these patients for the presence of metastases. The presence of a parenchymal lung nodule (greater than or equal to 1 cm if single and 0.5 cm if multiple) with a soft tissue component without calcification on lung and mediastinal window settings was considered positive for the presence of metastasis. All other patients were considered as not having any lung metastases.

RESULTS

Of the 56 patients, 10 (17.9%) had evidence of pulmonary metastases on computed tomography. Of the 56 patients, there were 3 patients with stage T1, 24 with T2, 26 with T3, and 3 with stage T4 tumors. Of these 10 patients, 1 had a stage T2 tumor, 7 had T3, and 2 had stage T4 tumors. Statistical analysis using exact logistic regression showed the odds of getting lung metastases is an increasing function of tumor grade.

CONCLUSIONS

There is a high incidence of lung metastases in patients with rectal cancer, and thoracic computed tomographic scanning should be performed as part of a staging protocol in all patients before any form of treatment is planned. There is a higher incidence of lung metastases with higher T stage.