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Joost M Klaase

Publications and source records attributed to Joost M Klaase.

11 recordsLinked to original sources
PubMed2006

Factors influencing the local failure rate of radiofrequency ablation of colorectal liver metastases.

BACKGROUND: The prognosis of patients with colorectal cancer is poor, especially when there is distant metastatic disease. Local ablation of tumor by radiofrequency ablation (RFA) has emerged as a safe and effective new treatment modality, but its long-term efficacy may be hindered by renewed local tumor growth at the site of RFA. The objectives of this study were to identify risk factors for local RFA failure and to define exclusion criteria for RFA treatment of colorectal liver metastases. METHODS: A total of 199 lesions in 87 patients were ablated with RFA. Factors influencing local failure rates were identified and compared with data from the literature. RESULTS: The local failure rate was 47.2%, and the average time to local disease progression was 6.5 months. Factors that significantly correlated with increased failure rates were metachronous occurrence of liver metastases, large mean lesion size, and central tumor location. CONCLUSIONS: Because accurate electrode placement is pivotal in achieving adequate tumor necrosis, RFA should not be performed percutaneously when electrode placement is impaired. We suggest that lesions >5 cm and lesions located near great vessels or adjacent organs should be treated with open RFA, thus allowing vascular inflow occlusion and complete mobilization of the liver. Lesions that are difficult to reach by electrodes should be approached by an open procedure.

Adult↗
PubMed2005

Anterior resection of rectal cancer without bowel preparation and diverting stoma.

PURPOSE: Since the introduction of total mesorectal excision (TME) as the standard operation technique for rectal cancer, anastomotic leakage percentages of up to 18% have been reported. To prevent such leakage, the use of mechanical bowel preparation and also the construction of a diverting ileostoma or colostomy have been standard procedures for years. In our institute, however, all patients undergoing colorectal surgery are operated upon without these measures. The present study was undertaken to investigate the results of this strategy in terms of the occurrence of postoperative anastomotic leakage. METHODS: All patients who underwent an elective (low) anterior resection between January 1996 and December 2001 (n = 144) entered the study. The clinical and pathological records of these patients were reviewed retrospectively. The exclusion criteria were patients with fixed rectal carcinoma who received preoperative radiotherapy and/or a stoma only at operation, emergency operations, abdominoperoneal resections, and Hartmann's procedures. RESULTS: Anastomotic leakage occurred in 7 out of 144 patients (4.9%). There was a trend toward a higher leakage frequency in men, in patients with a distal anastomosis, in patients with a stapled anastomosis, and in patients with a T3-T4 tumor or with positive lymph nodes. None of these factors, however, had a significant prognostic value based on a univariate or multivariate analysis. Those who died after leakage tended to be older than those who did not (P < 0.05). CONCLUSION: A (low) anterior resection can be performed safely without mechanical bowel preparation or a diverting stoma, and results in an anastomotic leakage percentage of less than 5%. Appropriate selection of patients may be important, but none of the investigated patient- or tumor-related factors could be identified as decisive.

Adult↗
PubMed2004

Lymphatic drainage routes of the gastric cardia visualized by lymphoscintigraphy.

UNLABELLED: This study was undertaken to assess the feasibility of lymphoscintigraphy of the gastric cardia and to identify the incidence of paraesophageal lymphatic drainage, precluding total gastrectomy with esophagojejunostomy as a potentially curative therapy for gastric cardia cancer. METHODS: Ten patients scheduled for esophagectomy with high-grade dysplasia or with esophageal cancer at least 3 cm above the esophagogastric junction were enrolled in this study. Preoperatively, 111 MBq of(99m)Tc-labeled nanocolloid (n = 5) or sulfur colloid (n = 5) were injected into the submucosa of the tumor-free cardia. Subsequently, lymphoscintigraphy in combination with CT was obtained. Locoregional lymph node stations were measured for radioactivity by a gamma-probe intraoperatively and ex vivo in the resection specimen. RESULTS: In each patient, at least 1 radioactive lymph node station was detected. In total, 42 radioactive lymph node stations were detected by gamma-probe. Of those 42 areas, 38 (90%) were visible at preoperative lymphoscintigraphy. In the group of 5 patients in whom nanocolloid was used, a median of 2 (range, 1-4) node stations per patient was identified, whereas when sulfur colloid was administered a median of 6 (range, 4-8) active lymph node stations per patient could be detected (P < 0.002). Paraesophageal drainage was identified in 1 patient. CONCLUSION: Lymphoscintigraphy of the gastric cardia is feasible and can accurately determine the location of radioactive lymph nodes. Early paraesophageal lymphatic drainage is rare.

Adenocarcinoma↗
PubMed2003

Long-term results of a double perfusion schedule using high dose hyperthermia and melphalan sequentially in extensive melanoma of the lower limb.

The aim of this study was to assess the results of an isolated limb perfusion (ILP) schedule with high dose hyperthermia (42-43 degrees C) and melphalan, applied sequentially in patients with advanced melanoma of the limbs. Seventeen patients with extensive recurrent or bulky melanoma of a limb were treated with hyperthermic femoral ILP (42-43 degrees C) without drugs followed by normothermic (37-38 degrees C) ILP with melphalan. Eleven patients (65%) had a complete response. Three patients (27%) had limb recurrences after 5, 6 and 18 months, respectively. The 5 year limb recurrence-free interval for patients with a complete response was 63%. Limb toxicity was mild; pressure-related blistering and transient sensory disturbances occurred after the hyperthermic ILP, and 88% of the patients had a grade II reaction (mild erythema and oedema) after the second ILP. This sequential ILP schedule resulted in a high complete response rate and a low limb-recurrence rate in patients with extensive, recurrent melanoma of the limbs at the cost of only mild toxicity. This regimen could be an alternative to ILP with tumour necrosis factor-alpha and melphalan.

Adult↗
PubMed2003

Local recurrence of rectal cancer after total mesorectal excision without preoperative radiotherapy.

BACKGROUND: At this moment, it is still debatable whether all patients with mobile rectal cancer who undergo surgical removal of the tumor should be treated with preoperative radiotherapy, since it is likely that only certain patients will benefit from this strategy. In this study, patients with mobile rectal cancer were immediately operated upon and only those with positive nodes or with incomplete resection received adjuvant radiotherapy. AIMS OF THE STUDY: To investigate the local recurrence rate after the use of a selective policy of adjuvant radiotherapy and to determine risk factors for local recurrence. METHODS: In a 5-yr-period, 178 patients with rectal cancer were referred to our institute. A total of 131 patients with mobile rectal cancer were treated with curative intent, which implied a microscopically radical resection and no signs of distant metastasis at operation. A retrospective analysis was undertaken to investigate the incidence of local recurrence in this curative group and to determine risk factors for local recurrence. RESULTS: The postoperative mortality in the curative group was 5.3%. Local recurrences were observed in 6 patients (4.6%) after a median period of 25 mo (range 11-37); two of them also had distant metastases detected at the same time. The highest local recurrence rates were seen in men (5.3%), in distal rectal cancers (6.9%), and in the node-positive group (8.7%). CONCLUSION: A low local recurrence rate can be achieved after total mesorectal excision (TME) without preoperative radiotherapy. Our results suggest using preoperative radiotherapy only for those patients who are at a higher risk for local recurrence. Staging techniques for selection of these patients are at this moments till inappropriate.

Adult↗
PubMed2002

Partial matrix excision or segmental phenolization for ingrowing toenails.

OBJECTIVE: To decide whether partial nail extraction with phenolisation or with partial excision of the matrix should be the standard treatment in patients with ingrowing toenails of the hallux. DESIGN: Randomized clinical trial with 12-month follow-up evaluations performed by observers who did not know which procedure was applied. SETTING: Outpatient department of a surgical teaching hospital. PATIENTS: Fifty-eight consecutive patients with a total of 63 ingrowing toenails were randomized. INTERVENTION: Thirty-four partial matrix excisions ("matrix" group) and 29 phenolizations ("phenol" group) were performed. MAIN OUTCOME MEASURES: Recurrence rate, postoperative morbidity (pain, wound exudates, and scar discomfort), and time to complete recovery (wearing shoes, performing normal activities/work). RESULTS: Recurrences were seen after 7 procedures in the matrix group and also after 7 procedures in the phenol group, of which patients were symptomatic and required a second operation in 4 and 3 instances, respectively. None of the observed differences in wound healing, postoperative pain, and recovery were statistically significant. CONCLUSIONS: Partial matrix excision and phenolization are equally effective in treating ingrowing toenails. Because the use of the toxic agent phenol should be avoided, partial matrix excision is the preferable procedure. But in view of the high recurrence rate, there is a need for further improvement of the treatment of ingrowing toenails.

Adolescent↗
PubMedDate not supplied

Endovascular treatment of traumatic thoracic aortic rupture combined with diaphragmatic rupture--a case report.

The purposes of this report are to describe the immediate repair of a diaphragmatic rupture and subsequent endovascular treatment of a thoracic aortic rupture secondary to blunt chest and abdominal trauma and to discuss the outcome in the light of the trauma scores. A 29-year-old man was injured in a car collision. There were signs of a left diaphragmatic rupture and spleen injury. After urgent laparotomy, the diaphragm was repaired. The spleen appeared uninjured; however, there was a dissection with a transmural tear of the thoracic aorta, which was subsequently treated intraluminally by using a Talent endovascular graft and two AneuRx aortic extension cuffs. The patient fully recovered, and the thoracic endograft showed no evidence of endoleak both 1 month and 1 year after treatment. Fourteen months after the operation, the patient is doing well. Endoluminal techniques can be used successfully in the immediate repair of thoracic aortic injuries, even in the presence of a diaphragmatic rupture. With the introduction of advanced repair modalities, such as endovascular techniques, mortality rates will decrease and may eventually alter injury-scoring systems such as the Injury Severity Score.

Accidents, Traffic↗