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Christophe Penna

Publications and source records attributed to Christophe Penna.

18 recordsLinked to original sources
PubMed2006

Anatomical basis for clamping of the right hepatic vein outside the liver during right hepatectomy.

The possibility and value of clamping the right hepatic vein (HV) outside the liver during right hepatectomy remain a matter of debate. We carried out an anatomical study on ten fresh cadaveric subjects with no abdominal scarring or hepatic lesions, to determine the biometry of the extraparenchymatous segment of the right HV. One or several accessory right HVs were found in 90% of cases on release of the right edge of the inferior vena cava (IVC). These accessory right HVs had a diameter greater than that of the superior right HV in 10% of cases. In 70% of cases, the extraparenchymatous segment of the vein was free of collateral branches, and in 30% of cases, it was joined by a branch close to its point of exit from the hepatic parenchyma. The length of the vein that can be clamped (length between the point of exit from the hepatic parenchyma and the point of entry of the right HV into the IVC) was 8.6 +/- 1.8 mm (6-12). The right HV entered the vena cava, at an acute angle, in 100% of cases. Clamping of the right HV was possible in all cases. Knowledge of these anatomical points makes it possible to isolate an extraparenchymatous segment of the right HV more safely. The right HV can be isolated and clamped outside the liver in more than 80% of cases, making it possible to carry out right hepatectomy on an exsanguinous liver.

Aged↗
PubMed2006

Complete response of colorectal liver metastases after chemotherapy: does it mean cure?

PURPOSE: Most patients with colorectal liver metastases (LMs) receive systemic chemotherapy. This study aimed to determine the significance of a complete response on imaging of LMs after chemotherapy. PATIENTS AND METHODS: Between 1998 and 2004, 586 patients were treated for colorectal LMs in one institution. Of these, 38 with the following criteria were included in the study: fewer than 10 LMs before chemotherapy; disappearance of one or several LMs on computed tomography (CT) scan and ultrasound; surgery with intraoperative ultrasound within 4 weeks of imaging; no extrahepatic disease; follow-up at least 1 year after surgery. RESULTS: Overall, 66 LMs disappeared after chemotherapy as seen on CT scan. Persistent macroscopic disease was observed at surgery at the site of 20 of 66 LMs, despite CT scan showing a complete response. The sites of 15 initial LMs that were not visible at surgery were resected. Pathologic examination of these sites of LMs, considered in complete response, showed viable cancer cells present in 12 of 15 cases. The sites of 31 initial LMs that were not visible at surgery were left in place during surgery; after 1 year of follow-up, 23 of 31 LMs considered in complete response had recurred in situ. Overall, persistent macroscopic or microscopic residual disease or early recurrence in situ were observed in 55 (83%) of 66 LMs having a complete response on imaging. CONCLUSION: In most patients receiving chemotherapy for colorectal LMs, a complete response on CT scan does not mean cure.

Aged↗
PubMed2006

Portal triad clamping (TC) or hepatic vascular exclusion (VE) for major liver resection after prolonged neoadjuvant chemotherapy? A case-matched study in 60 patients.

BACKGROUND: Prolonged systemic preoperative chemotherapy induces pathologic changes in liver parenchyma. The consequences of vascular occlusion on liver submitted to prolonged preoperative systemic chemotherapy are not known. The aim of this case-matched study was to assess which method of vascular occlusion is most appropriate for major liver resection in patients who have undergone prolonged preoperative systemic chemotherapy. METHODS: Among 305 patients who had liver resection for colorectal metastases from 1998 to 2003, 28 underwent major liver resections under portal triad clamping after more than 6 cycles of preoperative chemotherapy (TC group). These 28 patients were compared with 32 patients matched for age, sex, ASA status, number of liver metastases, type of liver resection, and type of preoperative chemotherapy, but who had major liver resection under hepatic vascular exclusion after more than 6 cycles of preoperative chemotherapy (VE group). RESULTS: There was no postoperative mortality. The morbidity rate was 18% after TC and 43% after VE (P = 0.044). Pulmonary complication rate was greater after VE (31% vs 3%, P = 0.017). The transfusion rate was 50% in the TC group and 40% in the VE group (P = 0.482). Postoperative changes of liver function tests were comparable in the two groups except for the prothrombin time, which was more prolonged from day 1 (P = 0.003) to day 5 (P = 0.04) after VE. CONCLUSION: Vascular occlusion can be used with no mortality and acceptable morbidity for major liver resection after prolonged preoperative chemotherapy. TC should be preferred to VE, permitted by the location of the neoplasm.

Adult↗
PubMed2006

KRAS mutation status is predictive of response to cetuximab therapy in colorectal cancer.

The anti-epidermal growth factor receptor (anti-EGFR) cetuximab has been proven to be efficient in metastatic colorectal cancer. The molecular mechanisms underlying the clinical response to this drug remain unknown. Genetic alterations of the intracellular effectors involved in EGFR-related signaling pathways may have an effect on response to this targeted therapy. In this study, tumors from 30 metastatic colorectal cancer patients treated by cetuximab were screened for KRAS, BRAF, and PIK3CA mutation by direct sequencing and for EGFR copy number by chromogenic in situ hybridization. Eleven of the 30 patients (37%) responded to cetuximab. A KRAS mutation was found in 13 tumors (43%) and was significantly associated with the absence of response to cetuximab (KRAS mutation in 0% of the 11 responder patients versus 68.4% of the 19 nonresponder patients; P = 0.0003). The overall survival of patients without KRAS mutation in their tumor was significantly higher compared with those patients with a mutated tumor (P = 0.016; median, 16.3 versus 6.9 months). An increased EGFR copy number was found in 3 patients (10%) and was significantly associated with an objective tumor response to cetuximab (P = 0.04). In conclusion, in this study, KRAS mutations are a predictor of resistance to cetuximab therapy and are associated with a worse prognosis. The EGFR amplification, which is not as frequent as initially reported, is also associated with response to this treatment.

Adult↗
PubMed2006

How to manage splenic rupture during major liver resection?

Spontaneous splenic rupture is a rare but life threatening complication of major liver resection with only five reported cases during major liver resection under hepatic vascular occlusion. We report two cases of splenic rupture during liver resection including the first case during portal triad clamping. In both patients, the hemorrhage was stopped by removing the vascular clamp. A splenectomy was performed in both patients and liver resection was completed under vascular clamping without complications. Although very rare, physicians should be aware of the possibility of splenic rupture during liver resection because instead of increasing vascular occlusion, clamp removal usually stops the hemorrhage.

Aged↗
PubMed2006

Influence of preoperative chemotherapy on the risk of major hepatectomy for colorectal liver metastases.

OBJECTIVE: : To assess the effects of preoperative systemic chemotherapy on remnant liver parenchyma, liver function, and morbidity after major liver resection for colorectal liver metastases. BACKGROUND: : Many patients operated upon for colorectal cancer liver metastases receive previous chemotherapy. Whether systemic chemotherapy alters liver parenchyma in such way that it increases the risks of liver resection remains unclear. PATIENTS AND METHODS: : Among 214 patients who received a liver resection for colorectal liver metastases between 1998 and 2002 in a single institution, 67 who underwent a major liver resection under total hepatic vascular exclusion form the basis of this report. Forty-five patients operated upon after systemic chemotherapy were compared with 22 who did not receive any chemotherapy in the 6 months prior to resection. Postoperative mortality, morbidity, liver function tests, and pathology of the resected liver in the two groups were compared. RESULTS: : There was no postoperative mortality. Values of liver function tests on days 1, 3, 5, and 10 were similar in both groups. Morbidity rate was higher in the chemotherapy group (38% versus 13.5%, P = 0.03). Postoperative morbidity was correlated with the number of cycles of chemotherapy administered before surgery but not to the type of chemotherapy. Preoperative chemotherapy was significantly associated with sinusoidal dilatation, atrophy of hepatocytes, and/or hepatocytic necrosis (49% versus 25%, P = 0.005). CONCLUSION: : Prolonged neoadjuvant systemic chemotherapy alters liver parenchyma and increases morbidity after major resection under total hepatic vascular exclusion, but it does not increase operative mortality. This should be taken into consideration before deciding a major liver resection in patients who have received preoperative chemotherapy.

Adult↗
PubMed2006

Rectal cancer.

Explore the source record for details and available documents.

Adenocarcinoma↗
PubMed2005

A common hepatic artery passing in front of the portal vein.

A variation in liver vascularization was discovered in a 50-year-old man. A single common hepatic artery was found to be responsible for vascularization of the entire liver. This artery was unusual in that it formed the first branch of the superior mesenteric artery, crossing the portal trunk shortly after its origin, and passed in front of the portal vein to reach the hilum of the liver, where it divided into a right and a left branch. This artery was a true common hepatic artery because a gastroduodenal artery emerged from it 2 cm after its origin. A common hepatic artery originating from the mesenteric artery and passing in front of the portal vein has never been described before. The patient had a second anatomical variation: the left gastric artery and the splenic artery arose directly from the aorta, without celiac trunk separation. This observation confirms the importance of carrying out a precise vascular assessment before all types of hepatic or pancreatic surgery, to identify possible variations in the number or trajectory of hepatic arteries.

Catheterization, Peripheral↗
PubMed2005

Accuracy of magnetic resonance imaging in rectal cancer depends on location of the tumor.

PURPOSE: This study was designed to evaluate prospectively magnetic resonance imaging for the prediction of the circumferential resection margin in rectal cancer to identify in which patient magnetic resonance imaging could accurately assess the circumferential resection margin before surgery and in which patients it could not. METHODS: During a 17-month period, a preoperative magnetic resonance imaging for the assessment of circumferential resection margin was obtained prospectively in 38 patients with mid or low rectal cancer. The agreement of magnetic resonance imaging and pathologic examination for assessment of circumferential resection margin was analyzed. RESULTS: Overall, magnetic resonance imaging agreed with histologic examination of the circumferential resection margin assessment in 28 patients (73 percent; kappa = 0.47). In all cases of disagreement between magnetic resonance imaging and pathology, magnetic resonance imaging overestimated the circumferential resection margin involvement. For the 11 patients with mid rectal cancer, circumferential resection margin was well predicted by magnetic resonance imaging in all cases (kappa = 1). For 27 patients with low rectal tumor, overall agreement between magnetic resonance imaging and histologic assessment was 63 percent (kappa = 0.35). Agreement was 22 percent (kappa = 0.03) for the 9 patients with low anterior and 83 percent (kappa = 0.67) for the 18 patients with low posterior rectal tumor. Univariate analysis revealed that only low and anterior rectal tumor was risk factor of overestimation of the circumferential resection margin by magnetic resonance imaging. CONCLUSIONS: Although magnetic resonance imaging remains the best imaging tool for the preoperative assessment of the circumferential resection margin in patients with rectal cancer, it can overestimate the circumferential resection margin involvement in low and anterior tumor with the risk of overtreating the patients.

Adult↗
PubMed2004

H-pouch: new isoperistaltic colonic pouch for coloanal anastomosis after rectal resection for cancer: a pilot study.

PURPOSE: To date, there is a consensus to consider colonic J-pouch-anal anastomosis as the standard form of reconstruction after proctectomy for cancer. However, one drawback of colonic J-pouch is evacuation difficulties, which are observed at some degree in almost one-half of patients. To improve functional outcome after coloanal anastomosis, we describe a new technique of isoperistaltic colonic H-pouch. METHODS: The functional results after construction of this pouch were assessed prospectively in ten patients and compared with those obtained in a control group of matched patients with a colonic J-pouch. RESULTS: At six months and one year, there were no differences between both pouches for bowel function, continence score, and evacuation difficulties. CONCLUSIONS: This preliminary study showed that the creation of a new isoperistaltic colonic H-pouch did not improve the functional results after coloanal anastomosis compared with colonic J-pouch. Because colonic H-pouch is technically more complex to fashion, it should not be performed routinely and the J-pouch remains the benchmark for routine clinical practice.

Adult↗
PubMed2003

[Hepatic metastases from colorectal cancer].

Over the last 30 years, the benefits of surgical resection and systemic chemotherapy in the management of hepatic metastases from colorectal cancer have been established. Actually, surgical resections are feasible with a very low mortality and a 5-year survival that approaches 50 %, but only 10 % to 20 % of patients are candidate to surgery. The others gain benefit from chemotherapy with more and more active drugs. To improve this overall picture, efforts have been made to increase the number of patients that could be candidates for surgery and to decrease the risk of recurrence after surgical resection. Shrinkage of tumours after administration of preoperative chemotherapy and availability of ablative techniques (radiofrequency and cryotherapy) now permit to treat with curative intent metastases initially considered as non resectable. Chemotherapeutic regimens to decrease the risk of postoperative recurrence are actually tested in clinical trials.

Catheter Ablation↗
PubMed2002

Colorectal metastasis (liver and lung).

Distant metastases are the major cause of death for colorectal carcinoma patients. Depending on the primary tumor's stage, liver metastases occur in 20% to 70% of patients and lung metastases in 10% to 20%. Unlike many other cancers, the presence of distant metastases from colorectal cancer does not preclude curative treatment. Surgical resection remains the only treatment that can ensure long-term survival and cure in some patients, but only a minority of liver metastases are amenable to surgery. New treatment modalities including portal vein embolization, perioperative chemotherapy and local destruction with cryotherapy or radiofrequency ablation may make more patients suitable for surgical resection of hepatic metastases and may prolong survival in cases of nonresectabilitv. The availability of new active drugs has changed the treatment of liver metastases from colorectal cancer.

Colorectal Neoplasms↗
PubMed2002

Surgery for colon and rectal cancer.

Radical surgery remains the only potentially curative treatment for colorectal cancer. Major changes in the principles of rectal cancer resection have been recently described (total mesorectum excision) whereas there have been few changes in the principles of colonic cancer resection. This chapter presents surgical procedures for curative treatment of colorectal cancer in both the elective and emergency settings.

Colonic Neoplasms↗
PubMed2002

Surgery of liver metastases from colorectal cancer: new promises.

For a long time, patients with liver metastases from colorectal cancer were considered to be incurable. Over the last 30 years, the benefits of surgical resection and systemic chemotherapy have been established. Actually, surgical resections are feasible with a very low mortality and a 5-year survival that approaches 40%, but only 10-20% of patients are candidates for surgery. The others gain benefit from chemotherapy with increasingly active drugs. To improve this overall picture, efforts have been made to increase the number of patients that could be candidates for surgery and to decrease the risk of recurrence after surgical resection. Shrinkage of tumours after administration of pre-operative chemotherapy and the availability of ablative techniques now allow the treatment, with curative intent, of metastases initially considered as non-resectable. Chemotherapeutic regimens have been developed to decrease the risk of postoperative recurrence.

Chemotherapy, Adjuvant↗