Biomedical subjects

Theo Wobbes

Publications and source records attributed to Theo Wobbes.

28 records · Page 2Linked to original sources

PubMed2004

Sentinel lymph node biopsy performed under local anesthesia is feasible.

BACKGROUND: A sentinel lymph node (SLN) biopsy in breast cancer patients, performed under local anesthesia (LA), could have advantages such as more efficient use of operating room time and pathologist time. It also provides a histologic diagnosis before definitive breast surgery is undertaken. The aim of this study was to assess feasibility by comparing the results of SLN procedures performed under LA versus general anesthesia (GA). METHODS: The SLN procedure was performed in 50 consecutive outpatients and 167 inpatients with clinical T1-2N0 breast cancer while they were under LA and GA, respectively. The SLN detection rate, a comparison of mapped and harvested SLNs, was compared for both groups. The duration of the SLN biopsies performed under LA was also measured. RESULTS: For both groups a median of 2 SLNs/patient were harvested. The detection rate was 1.00 for the LA group and 0.99 for the GA group. The learning curve for SLN procedures under LA showed a decrease in duration for the consecutive months (not significant). CONCLUSIONS: SLN biopsy can be safely and adequately performed with the patient under LA. It allows early diagnosis of the lymph node status, acquired on an outpatient basis, with minimal discomfort to the patient. The learning curve demonstrated that the LA procedure can quickly be mastered if the surgeon is experienced in performing SLN biopsies.

Ambulatory Surgical Procedures↗

PubMed2004

The role of MRI in invasive lobular carcinoma.

PURPOSE: To determine the value of MR imaging in the detection and measurement of tumor size in patients with invasive lobular carcinoma (ILC) compared to mammography and ultrasound. MATERIALS AND METHODS: From 36 cases of ILC in 34 patients who were surgically treated, the pre-operative imaging measurements, being mammography, ultrasound and contrast enhanced MR, were retrospectively re-evaluated for tumor detection and size. Findings were compared with pathology. Two radiologists were used for evaluation of the mammograms, the other imaging modalities were only evaluated by one radiologist. The Pearsons correlation test was used to determine the correlation between histopathological and imaging measurements for each imaging modality. RESULTS: For mammography, ultrasound and MRI the false negative scores were respectively 14%, 3% and 0%. The percentage for underestimated, correctly estimated and overestimated measurements on imaging were 56%, 33% and 11% for radiologist 1 and 50%, 33% and 17% for radiologist 2 on mammography. For ultrasound and MRI these percentages were respectively 53%, 47%, 0% and 14%, 75%, 11%. The correlation coefficients for mammography were respectively r = 0.34 (p < 0.05) and r = 0.27 (p > 0.05) for both radiologists, for Ultrasound r = 0.24 (p > 0.05) and for MRI r = 0.81 (p < 0.01). CONCLUSION: Of the three imaging modalities contrast enhanced MR has the lowest false negative rate in detecting ILC and has the highest accuracy in measuring the size of the ILC. MR could play a key role in the pre-operative work-up for accurate tumor size determination.

Adult↗

PubMed2003

Limb salvage in musculoskeletal oncology.

Since the early 1970s, substantial progress in dealing with musculoskeletal tumours has been made, with improvements in surgical skills, radiology, chemotherapy, pathology, and radiotherapy. Nowadays, 70-85% of all malignant tumours are treated by limb salvage, without compromising the oncological result. After many years, the functional result that may be achieved with a limb-saving procedure is becoming clear. Limb salvage has cosmetic advantages, but whether the quality of life of these patients is superior to that of those who undergo amputation is unclear. The non-oncological complication rate is much higher after limb salvage than after amputation, and consequently additional surgery is necessary. In the future, the co-operating disciplines should strive for better survival of these patients, for which the development of new chemotherapeutic drugs is especially needed.

Bone Neoplasms↗

PubMed2003

Stage migration in breast cancer: surgical decisions concerning isolated tumour cells and micro-metastases in the sentinel lymph node.

AIMS: Sentinel lymph node biopsy has replaced the axillary lymph node dissection (ALND) in primary surgery for breast cancer in many hospitals and is expected to become the standard of care in due time. Since the sentinel lymph node is subjected to more extensive pathologic examination than the lymph nodes in the axillary dissection specimen, more patients are found to be node positive (N+); however many of them contain micro-metastases (<or=2mm). The consequence may be an overshoot of therapy: additional surgery for non-metastatic lymph nodes or systemic adjuvant therapy. METHODS: We examined 34 (out of a series of 38) clinically T1 (cT1) patients who had a SLN biopsy with or without ALND and compared them to a matched historical control group. RESULTS: Twenty-one of 34 (62%) patients showed tumour cells in their SLN's. From these 21 patients in 13 (62%) the SLNs contained isolated tumour cells, of which 10 (77%) were detected only by immunohistochemistry (IHC), in four (19%) the SLNs contained micrometastases, and in four (19%) macrometastases. From 16 patients with isolated tumour cells or micrometastases in the SLN who underwent a regular ALND one had an H&E detected isolated tumour cell in a non-SLN and one patient with isolated tumour cells in the SLN who did not get a regular ALND developed an axillary recurrence 11 months after the primary treatment. On the other hand, three of four (75%) patients with macrometastases in the SLN had pathologically involved non-SLNs. In the majority (70%) of patients of the historical control group no lymph node involvement was seen. The percentage of macrometastases staged as lymph node positive in the control group was the same as in the studied group. CONCLUSION: Most patients with cT1 breast cancer with isolated tumour cells or micrometastases in the SLN will not benefit from additional axillary dissection; 88% had a negative ALND. Since we cannot select the group that will benefit from ALND, this is still indicated in case of isolated tumour cells or micrometastases in the SLN. Since most of the affected SLNs show isolated tumour cells and are classified as pN0(i+), stage migration due to more meticulous pathologic examination does not occur according to the TNM classification. However some patients do not benefit from the introduction of the SLN, due to the high incidence of isolated tumour cells or micrometastases in the SLN. Many more patients than expected still end up with an ALND.

Axilla↗

PubMed2002

Effect of blood sample handling and reverse transcriptase-polymerase chain reaction assay sensitivity on detection of CK20 expression in healthy donor blood.

Data concerning the specificity of cytokeratin 20 (CK20) as a reverse transcriptase-polymerase chain reaction analysis (RT-PCR) marker to detect disseminated tumor cells in blood are conflicting. Underlying causes for these discrepancies need to be determined to clarify the significance of CK20 detection. Because differences in RT-PCR assays and blood sample handling may be important, their influence on CK20 detection was studied. Using a series of healthy donor blood samples spiked with colon tumor cells, the authors compared the sensitivities of two conventional PCRs with different primer sets and a quantitative LightCycler PCR (Roche Diagnostics GmbH, Penzberg, Germany). Additionally, the influence of sample collection and preparation on assay specificity was studied by examining CK20 expression in the mononuclear cell fraction (MNC) of the first and the second aliquot of blood drawn from healthy donors and in the granulocyte cell fraction. At the concentration of one spiked tumor cell/mL blood, the CK20 detection frequency varied from 17% and 67% for the conventional to 78% for the LightCycler PCR. In the unspiked samples, CK20 was detected in 0% and 8% of the conventional and in 11% of the LightCycler PCR tests. Quantitative analysis revealed that CK20 was expressed at a high level in the granulocyte samples. The results demonstrate that differences in assay sensitivity and sample handling influence CK20 detection in blood.

Antigens, CD20↗

PubMed2002

The relation between perceived inequity, marital satisfaction and emotions among couples facing cancer.

The central aim of the present study was to examine if equity theory still applies to intimate relationships when couples are confronted with a serious illness. Equity concerns were examined among 68 cancer patients and their partners. Contrary to our expectations, only male patients on average felt overbenefited in their relationship, whereas female patients on average felt equitably treated. Moreover, it was found that the partners of these patients did not, as was expected, feel underbenefited in their relationship. The main focus of the present study was on the association between perceived equity on the one hand and relationship satisfaction and emotions on the other. It was found that in general patients seemed most sensitive to underbenefit (i.e. they felt least satisfied), and experienced on average least positive and most negative affect when they felt underbenefited. Particularly, patients who were physically impaired felt dissatisfied and angry when underbenefited. The partners of these patients were in general equally sensitive to inequity in both directions, regardless of their ill partner's physical condition.

Activities of Daily Living↗

PubMed2002

Failing in spousal caregiving: The 'identity-relevant stress' hypothesis to explain sex differences in caregiver distress.

OBJECTIVES: This study examined a possible explanation for the frequently reported finding that female caregivers perceive more psychological distress than do male caregivers. Our 'identity-relevant stress' hypothesis asserts that feelings of incompetence with respect to caregiving are more strongly associated with psychological distress in women than in men. Women who feel competent with respect to caregiving may report levels of distress as low as that of male caregivers. DESIGN: This study has a cross-sectional design. METHODS: Psychological distress (CES-D) was measured in 32 female and 36 male partners of patients suffering from various types of cancer. Furthermore, partners' perceptions of caregiving performance and patients' perceptions of partners' supportive and unsupportive behaviour were assessed. RESULTS: Only among female partners were self-efficacy and personal accomplishment regarding caregiving found to be positively linked to distress. Also, in contrast to male partners, female partners reported more distress when they acted less supportively. CONCLUSION: The difference in psychological distress between female and male caregivers seems to be carried by a subgroup of partners who feel that they are not doing a very good job at caregiving.

Journal Article↗

PubMed2001

Critical analysis of the treatment of non-palpable breast cancer: toward a less invasive future?

Results and experience with the treatment of non-palpable breast cancer are reported and related to the future of less invasive treatment of small breast cancers. The retrospective study included 102 patients treated between 1980 and 1993 at the University Hospital of Nijmegen. Most cancers were screen-detected. Tumor sizes on pathological examination proved 3 mm (SD 7.7 mm) larger than on mammography (p = 0.0029). pT1 tumors were encountered in 77 patients (75%); pT2 tumors in 17 patients (17%). Seventy-five patients were free of lymph node metastases, 26 patients showed stage pN1 (25%). Most patients had invasive ductal cancers. Only two patients died of breast cancer. A 10-year disease-free survival of 94% was calculated, after excluding four patients with known systemic disease (M1) at diagnosis. T1a, T1b, and T1c had a 10-year survival of 100%, 96%, and 96%, respectively. Early detection and multimodality treatment of breast cancer have significantly improved survival. Inpatients with small breast cancer tumors future developments in treatment must be aimed at the use of less invasive techniques, reducing morbidity while maintaining high levels of disease-free survival.

Adult↗

PubMedDate not supplied

MRI-guided preoperative wire localization of nonpalpable breast lesions.

With the increasing use of magnetic resonance imaging (MRI), the physician is more frequently confronted with nonpalpable breast lesions that are only visible on MRI. In these cases, it is often difficult to obtain adequate material for pathological examination. One of the methods that may be performed is excisional biopsy after MRI-guided wire localization. This study intends to examine the feasibility and added benefit of this method. It appears to be a reliable and useful tool that is, therefore, of additional benefit to surgical practice.

Adult↗

PubMedDate not supplied

No association between genetic polymorphisms in NAD(P)H oxidase p22phox and paraoxonase 1 and colorectal cancer risk.

BACKGROUND: Impaired metabolism of ingested toxic or carcinogenic compounds is a postulated mechanism underlying colorectal cancer (CRC). Furthermore, it is suggested that reactive oxygen species (ROS) may play a role in human cancer development. Polymorphic variations in NAD(P)H oxidase p22phox and paraoxonase 1 (PON1) enzyme activities may alter superoxide production or the rate of chemical metabolism, respectively, and this may influence the risk for CRC. Therefore, this study was designed to determine whether the distribution of polymorphisms in NAD(P)H oxidase p22phox and PON1 genes was different in sporadic CRCpatients versus healthy controls. MATERIALS AND METHODS: The study participants (365 cases and 354 controls) were all of Caucasian origin. NAD(P)H oxidase p22phox H72Y, and PON1 L55M and Q192R polymorphisms were genotyped by polymerase chain reaction, eventually followed by restriction-fragment-length-polymorphism analyses. RESULTS: Comparison of CRC patients and controls revealed no significant differences in genotype distributions or allele frequencies for polymorphisms in the NAD(P)H oxidase p22phox and PON1 genes. Investigation of potential associations between the variant NAD(P)H oxidase p22phox or PON1 alleles and the clinical characteristics, tumour location or tumour stage, also did not reveal statistically significant associations. CONCLUSION: Variant genotypes of NAD(P)H oxidase p22phox and PON1 do not contribute to the susceptibility to CRC.

Adult↗