Biomedical subjects

I Köves

Publications and source records attributed to I Köves.

At least 19 recordsLinked to original sources

PubMed2002

The time-course of metastases from breast cancer after mastectomy and breast-conserving surgery with and without isolated local-regional recurrence.

We have examined time intervals between events in 390 metastatic breast cancer (MBC) patients whose distant failure developed within 10 years from initial surgery of Stage I/II disease. All of the patients underwent axillary dissection and mastectomy (n=295) or breast-conserving surgery (BCS, n=95), between 1983 and 1987. Distinctions have been made between distant failure with (n=79) and without (n=311) isolated local-regional recurrence (LRR). The median survival time after first relapse was significantly longer with intrabreast (30 months) and chest wall (24 months) than with distant relapse (15 months), but with axillary (17 months) or with supraclavicular (17 months) relapse survival was similar. The delay between LRR and distant metastasis was shorter with axillary (7 months) and supraclavicular (9 months) than with breast (20 months) and chest wall (12 months) recurrences. The median postmetastatic survival time by site of first relapse was significantly shorter with supraclavicular (6 months) and axillary (9 months) than with distant site relapse (15 months) but with intrabreast (12 months) or with chest wall (11 months) recurrence survival was similar. In MBC, regional recurrences are associated with a shorter interval between events than with local recurrences. The shortened intervals for patients with regional recurrence suggest that metastases existed at the time of initial surgery. The question of whether prevention of local or regional recurrence or both improves cause-specific survival after mastectomy or BCS needs to be answered in randomized studies.

Journal Article↗

PubMed2002

Inguinal sentinel lymph node biopsy for staging anal cancer.

BACKGROUND AND AIMS: The optimal treatment of clinically negative inguinal lymph nodes in patients with primary anal cancer has not yet been clearly defined. The presence of metastases in the inguinal lymph nodes is an adverse prognostic factor for anal cancer. In the present study the feasibility of sentinel lymph node biopsy (SLNB) for staging anal cancer was investigated. PATIENTS AND METHODS: From September 1999 to March 2002, 8 patients with biopsy proven primary anal cancer underwent lymphoscintigraphy and dual-agent guided inguinal SLNB for nodal staging before starting multimodality treatment. RESULTS: Inguinal SLNB was successful in all 8 patients (13 groins). A total of 20 hot and blue SLNs (mean 1,5 (1-2) per groins) were removed. In 2 patients (25%) the SLN was positive for metastasis. CONCLUSIONS: Lymphoscintigraphy followed by dual-agent guided inguinal SLNB is technically feasible for staging patients with primary anal cancer. The detection of metastases in the removed sentinel lymph node(s) may alter the treatment and thus may improve the locoregional control and overall survival of these patients.

Aged↗

PubMed2001

Alterations of K-ras and p53 mutations in colorectal cancer patients in Central Europe.

Many molecular investigations of colorectal cancer (CRC) have suggested that the accumulation of specific mutations in proto-oncogenes and tumor suppressor genes regulating cell growth via signal transduction trigger the stagewise progression to malignancy. In this study, the frequency, location, and type of mutations of the K-ras proto-oncogene exon I and p53 tumor suppressor gene exons 5-8 were analyzed in colorectal carcinomas of 65 patients from Central Europe, using polymerase chain reaction (PCR)-cold single-strand conformation polymorphism (SSCP) screening and direct sequencing. The incidence of K-ras activating mutations in these Central European samples was lower (25%) compared to that obtained in American and western European populations (40-50% at least), while the incidence of p53 inactivating mutations was similar (58%). These results suggest that some other genetically linked mechanisms may play a role in CRC development and progression, and hence K-ras and p53 mutations cannot be considered to be universal genetic markers for CRC.

Colorectal Neoplasms↗

PubMed2001

Endoscopy and autopsy follow-up of biodegradable oesophageal anastomoses in dogs.

The biofragmentable Anastomosis Ring (BAR) is a mechanical device composed of absorbable material and creates an inverting, atraumatic compressive anastomosis with no foreign material at the anastomotic site after healing. The aim of the present experimental study was to assess the safety of oesophagoscopy in early days after oesophageal anastomoses performed with the BAR and to follow-up the healing of BAR anastomoses by in vivo endoscopy and autopsy examination. Thirty mongrel dogs divided into subgroups according to the time-points of endoscopy and autopsy (4th, 7th, 14th, 28th day) were used. There was no significant difference in the healing of anastomoses performed under or above the tracheal bifurcation. Pleural adhesions helped to cover and seal small subclinical leaks. The mortality was 13.3% (4 dogs) and the overall leakage rate 14.3%. We looked for bleeding, haematoma, erosion, ulceration and granulation tissue in the anastomosis. Due to the high mechanical strength of these anastomoses, oesophagoscopy was a safe, easy and feasible method for follow-up BAR intrathoracic anastomoses, with no significant difference between the number of lesions found with endoscopy as compared to the autopsy data. The overall sensitivity of oesophagoscopy to discover mucosal lesions was 73.1%. Endoscopy had no complications, therefore it is a useful method of follow-up and may help predict the normal or compromised healing of oesophageal anastomoses.

Absorbable Implants↗

PubMed2001

[The effect of tumour bed boost on local control after breast conserving surgery. First results of the randomized boost trial of the National Institute of Oncology]

PURPOSE: To evaluate the effect of tumour bed boost on local tumour control (LTC) after breast conserving surgery in a prospective study. METHODS: Between 1995 and 1998, 207 women with early invasive breast cancer who underwent conservative operation were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either no further radiotherapy (n=103) or a boost to the tumour bed (n=104) with either 16 Gy electron (n=52) or 12-14.25 Gy high dose rate brachytherapy (n=52). RESULTS: At a median follow-up of 4.25 years the crude rate of local recurrence was 6.7% with and 13.6% without boost. The respective rates of tumour bed relapse were 3.8% vs. 10.7%. The 4 year probability of LTC, relapse-free survival and breast cancer-specific survival was 94.2% vs. 85.1% (p=0.1176), 82.3% vs. 67.2% (p=0.0438) and 84.8% vs. 90.9% (p=0.1111), respectively, in favour of the boost group. Systemic treatments had no significant impact on LTC (88.9% with and 89.6% without systemic treatment, p=0.8858). CONCLUSION: Tumour bed boost decreased the incidence of local and tumor bed relapses with a reduction of 50% and 64%, respectively. Relapse-free survival was improved significantly with boost. However, the influence of boost treatment on breast cancer-specific survival should be tested in further studies. In spite of the higher incidence of late radiation side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. The final results of the EORTC trial and other ongoing studies will help to clarify the indication of boost dose according to prognostic subgroups.

Journal Article↗

PubMed2001

[Oncocytic carcinoid tumor of the lung].

An elderly female patient was admitted and operated on for a lesion in the upper lobe of the right lung. After lobectomy the patient has recovered without complications. Histology proved oncocyter carcinoid tumour. This neuro-endocrine tumour is a rarity in the lungs with less than forty cases reported in the reviewed literature. This is the first case reported in Hungary.

Aged↗

PubMed2001

[Retrospective evaluation of surgically treated cases of non-palpable breast tumor].

Between 10.01.1997 and 09.30.1999 authors performed operations on 78 patients who had nonpalpable breast tumors. If mammography was considered abnormal during breast screening program patients were recalled. Besides clinical investigation complimentary mammograms were performed. After sonogram, and if needed, aspiration biopsy cytology (ABC) if necessary core biopsy (CB) was the next investigation. 79 operations were performed on 78 patients (one was patient had synchronous breast tumor). The mean age of the patients was 56.3 years. If the radiological investigations (R4-R5) and/or the ABC (C4-C5) or CB suggested malignancy operation was performed. Mammography suggested malignancy in 60.75% of the patients, it was suggested by ABC in 30.18%, and by CB in 55.5%. The nonpalpable tumor, suspected to be malignant was marked with a wire loop and was excised under anesthesia along with the affected breast sector. The excision and tissue-border around the tumor was checked by specimen mammography performed during the narcosis. No cryohistology was performed. After the specimen mammography, the wound was closed. The final histology of the operations showed malignancy in 40.5%. In their retrospective study the authors evaluated the complete sensitivity and the positive predictive value (PPV) of the preoperative investigations regarding the final histology. They analyse the value of preoperative mammogram, the ABC and CB in malignant and in benign cases. Early diagnosis and surgical treatment is expected to improve significantly the survival of patients with breast cancer. Reduction in the number of unnecessary operations can be expected from increasing the accuracy of radiological and cytological investigations and the adequate usage of core biopsy.

Biopsy, Needle↗

PubMed2001

Bursting strength and collagen content changes in esophageal anastomoses. Comparative experimental study in dogs.

BACKGROUND AND AIMS: The Biofragmentable Anastomosis Ring (BAR) is a mechanical device composed of absorbable material, performs an inverted anastomosis by atraumatic compression. It is a safe method recommended for bowel ends covered by serosal layer. The feasibility for esophageal surgery hasn't been proved. In our study we compared the healing of transsected intrathoracic esophagus anastomosed with BAR versus Stapler on an experimental dog model by evaluating the bursting strength (BS) and collagen (Hydroxyproline (HP)) concentration and content in different sites and defined time points after surgery (4th, 7th, 14th, 28th day). MATERIAL AND METHODS: Forty-six mongrel dogs were randomly separated into two groups (28 BAR, 18 Stapler) and parameters of surgical repair evaluated after sacrification on certain days. RESULTS: Although we had a total of 4 leaks (14,3%) only in the BAR group (2 were clinically relevant and fatal), there was no significant difference in the leakage rate between the two groups. BS was significantly higher in the BAR group during the first week with values almost equal from the 14th day, in both groups. BS measurement reflects anastomotic strength only during the first two postoperative weeks. After this rupture is often produced outside the anastomotic line. HP concentration showed no significant differences from samples taken next to and far from the anastomotic line. The HP rate showed a significant reduction in the 4th and 7th day subgroups, and values close to the reference from the 14th day with both techniques. CONCLUSIONS: BS and HP changes proved a normal tissue repair with no significant difference, showing that both methods are suitable to perform anastomoses on the intrathoracic esophagus in mongrel dogs. The higher mechanical stability of the BAR anastomosis could suggest the feasibility of the method in conditions where higher mechanical strength is requested.

Anastomosis, Surgical↗

PubMed2000

Experimental and clinicopathologic studies on the function of the HGF receptor in human colon cancer metastasis.

The organ-specific metastasis characterizes several human cancers, including colon carcinoma, a disease that frequently involves metastases in the liver. The data on the molecular mechanisms of liver metastasis would therefore be highly useful for prognostic purposes. Although the upregulation/amplification of the hepatocyte growth factor (HGF) receptor, c-met, has been frequently observed in colon cancer metastasis, the actual functional significance of the feature in the liver metastatization is not yet known. We have used three human colon carcinoma cell lines (HT29, HT25 and WiDr), characterized by different liver metastatic potentials in SCID mice, to analyze the expression of c-met and the biological effects of HGF. We found that HGF induces scattering in in vitro liver-metastatic cell lines (HT25 and WiDr) only at doses which are non-mitogenic (1-20 ng/ml). Analysis of the c-met expression revealed that the metastatic cell lines express authentic c-met gene and protein material, unlike the non-metastatic HT29 cell line, which expresses only the c-terminal cytoplasmic domain of the c-met beta-chain. Interestingly, c-met was found to be localized in the substrate-attached peripheral membrane and partially colocalized with phosphotyrosine-proteins in the metastatic cells only when kept on fibronectin. On the other hand, we have analyzed 86 primary human colon cancers in Dukes' B (invasive but non-metastatic) and C (invasive and lymph node metastatic) stages. Western blotting of the proteins isolated from the tumor tissues and immunohistochemical control study on the paraffin samples of a third of these cases (25/86) all indicated a significant upregulation of the c-met protein in the Dukes' C tumor glands compared to the Dukes' B stages (P < 0.001 and P < 0.05, respectively). Since the two stages differ in the involvement of the regional lymph nodes but not in the invasion depth, the clinicopathological data and our experimental findings further support the notion that the c-met expression in human colon cancer can be considered as a marker of the metastatic potential due to its involvement in the generation of the motility signal.

Adenocarcinoma↗

PubMed2000

[Reexcision and perioperative brachytherapy in the treatment of local relapse after breast conservation: a possible alternative to mastectomy].

Breast conserving surgery and postoperative radiotherapy became widely accepted in the last two decades for the treatment of early invasive breast cancer. In spite of adequate surgery and radiotherapy, the rate of ipsilateral breast tumor recurrence is approximately 10%. In such cases salvage mastectomy is the standard treatment, however wide reexcision of the recurrent tumor is also a reasonable option for selected patients. The risk of second local relapse is higher following further breast conservation compared to mastectomy. The authors report the technique of tumor reexcision combined with intraoperative implantation and perioperative high dose rate (HDR) bracytherapy of the tumor bed for the salvage of recurrence in a previously irradiated breast. One can perform two operative interventions at the same time with this method. Irradiation can be started safely within 48 hours after surgery. A review of the literature is also performed by the authors to demonstrate the role and indication of perioperative brachytherapy in the treatment of breast tumor relapse and other cancer recurrences. Reexcision is a practicable alternative to mastectomy for solitary, parenchymal breast tumor relapse measured 2 cm or less in diameter. Perioperative brachytherapy may decrease the risk of second relapse without increasing radiation side effects. Further prospective study is required to define the value of the prescribed method in comparison with salvage mastectomy.

Aged↗

PubMed2000

[Initial experiences with sentinel lymph node biopsy in malignant melanoma].

Elective versus therapeutic lymph node dissection has been a controversial field of the surgical treatment of cutaneous malignant melanoma for more than two decades. The identification and biopsy of the sentinel lymph node in different solid malignancies has become feasible by the method described by Morton in 1992. The sentinel lymph node is the first tumor draining lymph node in the regional lymph node basin. If metastasis is not proven in the sentinel node by detailed histological study those are unlikely in other regional lymph nodes and formal lymph node dissection can be omitted. Patients undergoing surgery for primary cutaneous (intermediate or high risk) melanoma have been initiated in this feasibility study. Of the 40 patients the sentinel lymph node biopsy was unsuccessful in two and at least one positive sentinel lymph node was found in nine patients. The duration of the procedure is between five and 15 minutes. After this feasibility study further prospective and randomized studies are projected.

Adult↗

PubMed1999

[The role of intraoperative gamma-probe-guided sentinel lymph node biopsy in the treatment of malignant melanoma and breast cancer].

In the treatment of malignant tumors regional lymphadenectomy is used for two purposes. It is used partly for staging the regional lymph nodes which is a significant and independent prognostic factor and determines the need for adjuvant oncologic treatment and partly for achieving locoregional disease control. Removal of tumor-free lymph nodes by regional lymph node clearance is unnecessary according to our current knowledge. Since the sensitivity and specificity of non-invasive clinical examinations are insufficient in predicting the nodal status the histological study of the regional lymph nodes cannot be abandoned. A new and minimally invasive surgical procedure, the mapping and removal of the first tumor draining lymph node, the sentinel node provides the possibility of pathological nodal staging without performing formal lymphadenectomy. Mapping of the sentinel node can be performed by the use of a radioisotope and intraoperative hand-held gamma-probe or a vital blue dye or a combination of these two. This latter method was used by the authors in 73 patients (25 with malignant melanoma and 48 with breast cancer). Sentinel lymph node biopsy was performed successfully in 92% of patients with melanoma and 90% of patients with breast cancer. In three breast cancer patients the sentinel node inaccurately predicted the axillary status as negative, but is was in 93% accurate in predicting the histologic nodal state. According to our preliminary experiences intraoperative gamma-probe guided sentinel lymph node biopsy is considered a feasible procedure in both malignant melanoma and breast cancer. More experiences are needed before introducing this method in the routine clinical practice.

Biopsy↗

PubMed1997

[Experience in the treatment of breast sarcomas].

Authors operated on 6339 malignant breast tumors at the Department of Surgery, National Institute on Oncology between 1980 and 1994. The records of 14 patients with sarcomas of the breast were analyzed. These included 2 malignant phyllodes tumors, 3 malignant fibrous histiocytomas, 2-2 fibrosarcomas and carcinosarcomas and liposarcoma, angiosarcoma, leiomyosarcoma, osteosarcoma and dermatofibrosarcoma protuberans one of each. During this period 5 patients died, 9 are living without evidence of tumor. Analysing these 14 cases authors present their policy in surgical therapy of breast sarcomas compared with literature data. They emphasise the importance of wide resection margins for prevention of tumor progression. The above mentioned principle is valid for local recurrences so radicalization of the previous conservative breast surgery may be necessary in selected cases. Intraoperative histological examination is recommended to verify that the resection margins are tumor free. Axillary block dissection is not necessary except in cases when palpable, firm lymph nodes are present in the region. Depending on the histological grade adjuvant radiotherapy could be considered but its effectiveness is not proven.

Adult↗

PubMed1996

[Pregnancy and colorectal cancer].

Among 1761 patients operated on for colorectal malignancies by the authors in a period of 20 years, four cases were diagnosed during pregnancy. Beside analyzing the case-histories they present the relevant literature data: the incidence of colorectal tumors during pregnancy is 4-5 cases/100,000 pregnancies, and most frequently they are situated in the rectum. The prognosis of primary colorectal malignancies diagnosed during pregnancy is unfavourable, and their biological behavior is more aggressive. Authors review the advised diagnostic and therapeutic approaches in different periods of pregnancy.

Adenocarcinoma↗

PubMed1996

[Aspiration cytology in the diagnosis of gastrointestinal tumors].

Early experiences with the new endoscopic aspiration cytology method in the diagnosis of gastrointestinal malignancies are discussed. It was performed in five patients in case of gastric and cardiac cancers and in fifteen ones of colon tumours. Results are compared with those of biopsies and brush cytologies. The new method is quick, reliable and suggested to be widely used in the gastrointestinal endoscopy.

Adenocarcinoma↗

PubMed1994

Malignant colorectal tumours in young adults.

The therapeutic and diagnostic problems of colorectal cancers in young adults (under the age of 40 years) are discussed, with special considerations to the unfavourable prognosis and its underlying causes. At the Department of Surgery, National Institute of Oncology, Altogether 638 patients were treated for colorectal cancer in the course of 10 years (1975-1985). From them 34 (5.2%) were younger than 40 years old. The 5-year survival of patients younger than 40 years was 38%, while that of those older than 40 years accounted for 48%. The importance of the prudence of the general practitioners is emphasized.

Adolescent↗

PubMed1994

Dixon's anastomosis with "double-stapling" technique: experience with 235 cases.

The perioperative results of 235 Dixon's anastomoses performed between 1985 and 1994 are compared to those of 125 Dixon's anastomoses performed between 1956 and 1979, on the basis of recurrences and survival data. It is concluded that the operations carried out with double stapling are considerably superior interventions with respect to speed, sterility and anastomotic safety and involve less complications. There is no difference between the stapling and handsewn techniques concerning the development of local recurrences. A further advantage of stapling is that it makes possible the saving of the sphincter more often, namely in almost 50% of the cases.

Anastomosis, Surgical↗

PubMed1994

Re-resection of the short cicatricial stenosis of colorectal anastomoses with EEA stapler.

Following 245 stapled anastomoses reoperation was necessary in 4 cases because of non-tumourous stenoses. In each of the 4 cases re-resection was performed according to authors' method, with EEA stapler, without the mobilisation of the rectum. The method is considered suitable for non-tumourous anastomotic stenoses involving short rectal segments.

Anastomosis, Surgical↗