Minimally invasive surgery in the diagnosis and treatment of upper gastrointestinal tract malignancy

Diagnostic accuracy of laparoscopy following computed tomography (CT) scanning for assessing the resectability with curative intent in pancreatic and periampullary cancer

BACKGROUND

Surgical resection is the only potentially curative treatment for pancreatic and periampullary cancer. A considerable proportion of patients undergo unnecessary laparotomy because of underestimation of the extent of the cancer on computed tomography (CT) scanning. Laparoscopy can detect metastases not visualised on CT scanning, enabling better assessment of the spread of cancer (staging of cancer). This is an update to a previous Cochrane Review published in 2013 evaluating the role of diagnostic laparoscopy in assessing the resectability with curative intent in people with pancreatic and periampullary cancer.

OBJECTIVES

To determine the diagnostic accuracy of diagnostic laparoscopy performed as an add-on test to CT scanning in the assessment of curative resectability in pancreatic and periampullary cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE via PubMed, EMBASE via OvidSP (from inception to 15 May 2016), and Science Citation Index Expanded (from 1980 to 15 May 2016).

SELECTION CRITERIA

We included diagnostic accuracy studies of diagnostic laparoscopy in people with potentially resectable pancreatic and periampullary cancer on CT scan, where confirmation of liver or peritoneal involvement was by histopathological examination of suspicious (liver or peritoneal) lesions obtained at diagnostic laparoscopy or laparotomy. We accepted any criteria of resectability used in the studies. We included studies irrespective of language, publication status, or study design (prospective or retrospective). We excluded case-control studies.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed data extraction and quality assessment using the QUADAS-2 tool. The specificity of diagnostic laparoscopy in all studies was 1 because there were no false positives since laparoscopy and the reference standard are one and the same if histological examination after diagnostic laparoscopy is positive. The sensitivities were therefore meta-analysed using a univariate random-effects logistic regression model. The probability of unresectability in people who had a negative laparoscopy (post-test probability for people with a negative test result) was calculated using the median probability of unresectability (pre-test probability) from the included studies, and the negative likelihood ratio derived from the model (specificity of 1 assumed). The difference between the pre-test and post-test probabilities gave the overall added value of diagnostic laparoscopy compared to the standard practice of CT scan staging alone.

MAIN RESULTS

We included 16 studies with a total of 1146 participants in the meta-analysis. Only one study including 52 participants had a low risk of bias and low applicability concern in the patient selection domain. The median pre-test probability of unresectable disease after CT scanning across studies was 41.4% (that is 41 out of 100 participants who had resectable cancer after CT scan were found to have unresectable disease on laparotomy). The summary sensitivity of diagnostic laparoscopy was 64.4% (95% confidence interval (CI) 50.1% to 76.6%). Assuming a pre-test probability of 41.4%, the post-test probability of unresectable disease for participants with a negative test result was 0.20 (95% CI 0.15 to 0.27). This indicates that if a person is said to have resectable disease after diagnostic laparoscopy and CT scan, there is a 20% probability that their cancer will be unresectable compared to a 41% probability for those receiving CT alone.A subgroup analysis of people with pancreatic cancer gave a summary sensitivity of 67.9% (95% CI 41.1% to 86.5%). The post-test probability of unresectable disease after being considered resectable on both CT and diagnostic laparoscopy was 18% compared to 40.0% for those receiving CT alone.

AUTHORS' CONCLUSIONS

Diagnostic laparoscopy may decrease the rate of unnecessary laparotomy in people with pancreatic and periampullary cancer found to have resectable disease on CT scan. On average, using diagnostic laparoscopy with biopsy and histopathological confirmation of suspicious lesions prior to laparotomy would avoid 21 unnecessary laparotomies in 100 people in whom resection of cancer with curative intent is planned.

Diagnostic accuracy of laparoscopy following computed tomography (CT) scanning for assessing the resectability with curative intent in pancreatic and periampullary cancer

BACKGROUND

Surgical resection is the only potentially curative treatment for pancreatic and periampullary cancer. A considerable proportion of patients undergo unnecessary laparotomy because of underestimation of the extent of the cancer on computed tomography (CT) scanning. Laparoscopy can detect metastases not visualised on CT scanning, enabling better assessment of the spread of cancer (staging of cancer). There has been no systematic review or meta-analysis assessing the role of diagnostic laparoscopy in assessing the resectability with curative intent in patients with pancreatic and periampullary cancer.

OBJECTIVES

To determine the diagnostic accuracy of diagnostic laparoscopy performed as an add-on test to CT scanning in the assessment of curative resectability in pancreatic and periampullary cancer.

SEARCH METHODS

We searched the Cochrane Register of Diagnostic Test Accuracy Studies, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE via PubMed, EMBASE via OvidSP (from inception to 13 September 2012), and Science Citation Index Expanded (from 1980 to 13 September 2012).

SELECTION CRITERIA

We included diagnostic accuracy studies of diagnostic laparoscopy in patients with potentially resectable pancreatic and periampullary cancer on CT scan, where confirmation of liver or peritoneal involvement was by histopathological examination of suspicious (liver or peritoneal) lesions obtained at diagnostic laparoscopy or laparotomy. We accepted any criteria of resectability used in the studies. We included studies irrespective of language, publication status, or study design (prospective or retrospective). We excluded case-control studies.

DATA COLLECTION AND ANALYSIS

Two authors independently performed data extraction and quality assessment using the QUADAS-2 tool. The specificity of diagnostic laparoscopy in all studies was 1 because there were no false positives since laparoscopy and the reference standard are one and the same if histological examination after diagnostic laparoscopy is positive. Therefore, the sensitivities were meta-analysed using a univariate random-effects logistic regression model. The probability of unresectability in patients who had a negative laparoscopy (post-test probability for patients with a negative test result) was calculated using the median probability of unresectability (pre-test probability) from the included studies and the negative likelihood ratio derived from the model (specificity of 1 assumed). The difference between the pre-test and post-test probabilities gave the overall added value of diagnostic laparoscopy compared to the standard practice of CT scan staging alone.

MAIN RESULTS

Fifteen studies with a total of 1015 patients were included in the meta-analysis. Only one study including 52 patients had a low risk of bias and low applicability concern in the patient selection domain. The median pre-test probability of unresectable disease after CT scanning across studies was 40.3% (that is 40 out of 100 patients who had resectable cancer after CT scan were found to have unresectable disease on laparotomy). The summary sensitivity of diagnostic laparoscopy was 68.7% (95% CI 54.3% to 80.2%). Assuming a pre-test probability of 40.3%, the post-test probability of unresectable disease for patients with a negative test result was 0.17 (95% CI 0.12 to 0.24). This indicates that if a patient is said to have resectable disease after diagnostic laparoscopy and CT scan, there is a 17% probability that their cancer will be unresectable compared to a 40% probability for those receiving CT alone.A subgroup analysis of patients with pancreatic cancer gave a summary sensitivity of 67.9% (95% CI 41.1% to 86.5%). The post-test probability of unresectable disease after being considered resectable on both CT and diagnostic laparoscopy was 18% compared to 40% for those receiving CT alone.

AUTHORS' CONCLUSIONS

Diagnostic laparoscopy may decrease the rate of unnecessary laparotomy in patients with pancreatic and periampullary cancer found to have resectable disease on CT scan. On average, using diagnostic laparoscopy with biopsy and histopathological confirmation of suspicious lesions prior to laparotomy would avoid 23 unnecessary laparotomies in 100 patients in whom resection of cancer with curative intent is planned.

Gastric cancer: Patterns of disease spread via the perigastric ligaments shown by CT

OBJECTIVE

The stomach is suspended in the abdominal cavity by perigastric ligaments, which are derived from the dorsal and ventral mesogastrium. These ligaments provide a direct contiguous pathway for the peritoneal spread of gastric cancer. In this article, we discuss the embryology and anatomy of the stomach and describe the specific ligamentous routes along which gastric cancers may spread by direct invasion.

CONCLUSION

Extragastric disease alters the prognosis and treatment options available to patients with gastric cancer. Familiarity with the stomach's embryology will help the radiologist understand its anatomy and, therefore, the patterns of regional spread of gastric cancer. The location of the primary tumor can predict involvement of specific perigastric ligaments because locoregional spread of gastric cancer occurs along the arteries, veins, nerves, and lymphatic channels within those ligaments. Thus, identifying the location of the primary tumor can potentially improve patient outcomes.

Laparoscopic pancreaticoduodenectomy: a retrospective review of 19 cases

The role of laparoscopic techniques in pancreatic surgery is still controversial especially regarding to exocrine malignancies. Operative time, conversion rate, adequacy of dissection, and morbidity do represent factors of major concern. Whereas laparoscopic resection of left sided pancreatic lesions requires no anastomosis and therefore has gained worldwide acceptance over the last years, excision of cephalic lesions by mimimal access has little place in surgeons' practice because of its technical complexity and duration of surgery. This study was designed to assess the feasibility and results of laparoscopic pancreaticoduodenectomy for neoplasms of the pancreatic head, analyzing steps of learning curve, conversion rate, and short-term outcomes. From August 2002 to December 2006, 19 patients affected by pancreatic neoplasm of the head were approached by minimally invasive technique. A video-assisted procedure with pancreaticoduodenal resection and anastomoses fashioned through a midline minilaparotomy of 7 cm was achieved in 7 patients. Conversion to laparotomy was required in 6 patients, in 3 for bleeding and in 3 for difficulties in dissection. Cephalic pancreatoduodenectomy was achieved by thorough intracorporeal technique in 6 patients. Mortality was nil. Oncologic principles with adequate lymphadenectomy and resection margins were respected and short-term outcomes and mean survival were quite acceptable and equal to those of conventional surgery.

Combined laparoscopic near-total gastrectomy and colectomy

Synchronous gastrointestinal lesions of the abdomen are uncommon. Although laparoscopic gastric resection and colonic resection have been previously described, the combined laparoscopic resection of these 2 organs is unique. We report a case of a 72-year-old man with in situ gastric cancer and high-grade dysplasia of a colon polyp who underwent successful laparoscopic resection of both lesions. This report highlights the importance of preoperative planning and port placement in combined laparoscopic procedures.

Survival of patients with periampullary carcinoma is predicted by lymph node 8a but not by lymph node 16b1 status

BACKGROUND

The aim of this study was to assess the impact of metastatic disease in lymph nodes 8a and 16b1 (as defined by the Japanese Pancreas Society) on survival in patients with periampullary malignancy.

METHODS

Patients undergoing resection for primary pancreatic ductal adenocarcinoma or intrapancreatic bile duct adenocarcinoma were identified from a prospective database (September 1997-May 2003).

RESULTS

Thirteen of 54 and ten of 44 evaluable patients had metastatic involvement of lymph nodes 8a and 16b1 respectively. Metastatic involvement of lymph node 8a was associated with a significantly shorter median survival (197 versus 470 days; P = 0.003) but metastatic involvement of lymph node 16b1 did not affect survival (457 versus 503 days; P = 0.185). Multivariate analysis showed lymph node 8a status to be the strongest predictor of outcome (P = 0.006). Median survival of those with metastatic lymph node 8a was not significantly different from that of 81 patients with overt metastatic periampullary cancer at the time of diagnosis (98 days; P = 0.072)

CONCLUSION

Lymph node 8a was an independent prognostic factor in patients with periampullary malignancy, but lymph node 16b1 was not. Survival in those with metastatic lymph node 8a was not significantly different from that in patients with metastatic disease at presentation. Preoperative determination of lymph node 8a status may have important implications in selecting patients for treatment.

Minimally invasive pancreatic surgery

Robotic surgery remains in its infancy, and little experience has been reported, as surgeons carefully explore the application of this type of technology to diseases of the pancreas. While challenging and controversial, Dr. Zollinger would most likely support the ongoing research in the techniques of pancreatic surgery that can lead only to an improvement in the outcomes of our patients.