Heat shock protein 70 expression following hepatic radiofrequency ablation is affected by adjacent vasculature.

BACKGROUND: Heat shock proteins are a highly conserved family of stress response proteins. Members of the heat shock protein 70 (Hsp70) family prevent protein misfolding and aggregation. Following radiofrequency ablation of unresectable liver tumors an interface appears between the irreversibly damaged and normal liver. The fate of this transition zone is critical and is believed to be responsible for local recurrences. Hsp70 is expressed in response to thermal stress and may influence the fate of cells in this transitional zone. It is also recognized that the presence of large vessels or a perivascular location of tumors also influences the recurrence rate. The aim of this study is to examine the transition zone and observe the effect of local blood flow on ablation morphology and Hsp70 expression. METHODS: Radiofrequency ablation was performed in 25 rats at various distances from the liver hilum. Tissue was retrieved and analysed at time points 0, 4, 24, 48 h, and 2 wk following treatment. Tissue was analyzed histologically with hematoxylin and eosin staining (H and E,) and immunohistochemically for Hsp70 expression. RESULTS: All rats survived the procedure. H and E staining revealed previously unreported foci of apoptosis at the ablation edge and deep in the normal hepatic parenchyma. Hsp70 was expressed in the transition zone at 4 h and peaked at 24 h. The degree of Hsp70 expression was significantly influenced by the distance from surrounding vasculature. CONCLUSIONS: This study reports several previously unreported findings. There is increased apoptosis distal to the ablated zone suggests leakage of radiofrequency (RF) current down blood vessels originating in the ablation zone. The degree of Hsp70 expression in the transition zone correlates with time after treatment and the size and location of any adjacent vasculature. These findings suggest that heat shock proteins may play a role in the ability of damaged cells to recover and survive at the periphery of an ablation zone.

Perspectives of laparoscopic donors toward a new procedure: transvaginal donor nephrectomy.

BACKGROUND: Interest in natural orifice transluminal endoscopic surgery (NOTES) is increasing. Transvaginal NOTES (TVNOTES) donor nephrectomy with subsequent removal of the kidney via the vagina is technically possible. This approach may minimize the surgical insult to the donor and allow improved cosmesis. The acceptability to patients of such a technique is, however, unknown. The aim of this article is to explore the attitudes of women who have previously undergone laparoscopic donor nephrectomy (LDN). METHODS: A 15-point questionnaire was designed by a multidisciplinary group of surgeons interested in minimally invasive surgery to obtain the views of women who had previously undergone LDN at the Queen Elizabeth Hospital, Adelaide. It was sent to 150 female donors, and their views with regard to the acceptability of a TV approach to the peritoneal cavity for donor nephrectomy were recorded. RESULTS: Forty-nine patients returned the completed questionnaire. The majority (90%) of these women did not have adverse feelings toward scars. Thirty-seven percent of women would consider a TVNOTES donor nephrectomy; however, this was increased to 51% if they could be reassured that TVNOTES was as safe as LDN. Concerns regarding a negative impact on sexual function after this procedure were raised by 33% of patients. The majority (88%) did not cite surgeon gender as an important factor when deciding for or against this procedure. CONCLUSIONS: This study demonstrates that less postoperative pain, better cosmesis, and safety are factors that may influence a patient's decision to choose TVNOTES donor nephrectomy. The majority, however, would still prefer LDN.

Transvaginal natural orifice translumenal endoscopic surgery (NOTES): a survey of women's views on a new technique.

BACKGROUND: Laparoscopic and minimally invasive surgery has changed the surgical landscape irrevocably. Natural orifice translumenal endoscopic surgery (NOTES) offers the possibility of surgery without visible scars. Transvaginal entry offers potential benefits because it gains access to the peritoneal cavity without the need to open an abdominal viscus. Much of the discussion pertaining to NOTES focuses on technical and training issues, with little attention to date paid to the opinions of women. The perceptions of female health care workers and patients were sought in relation to their views on transvaginal NOTES. METHODS: This study surveyed 300 women using a 12-point questionnaire devised by a multidisciplinary group of surgeons interested in minimally invasive surgery. The questionnaire was designed to establish the opinions of women with respect to NOTES surgery versus standard laparoscopic procedures. Responses were de-identified. RESULTS: Three-fourths of the women surveyed were neutral or unhappy about the prospect of a NOTES procedure, and this remained constant even when it was stipulated that laparoscopic cholecystectomy and NOTES had equivalent safety and efficacy. Younger nulliparous women were most concerned about the potential negative effect of NOTES on sexual function. A minority were concerned about the cosmetic effect of surgery, although surgical scars were perceived as more important to younger respondents. CONCLUSIONS: Potentially, NOTES surgery offers women a scarless operation with the possibility of less pain than experienced in standard laparoscopic surgery. Few women, however, were troubled about the cosmetic effect of surgery. The effect of NOTES on sexual function was expressed as a particular concern by younger women. In all groups and across all ages, peritoneal access using the transvaginal route was met by significant scepticism. In Australia, women remain to be convinced about the potential advantages of the emerging NOTES technology.

Efficacy and safety of microwave ablation for primary and secondary liver malignancies: a systematic review.

This article reviews the therapeutic efficacy and complications of microwave ablation (MWA) in the treatment of primary and secondary liver malignancies. A PubMed search using keywords 'microwave', 'liver', 'malignancy', 'cancer' and 'tumour' was performed to identify articles related to MWA of liver malignancies published in English from 1975 to February 2008. MWA is an effective treatment options for both primary and secondary liver malignancies with survivals comparable with those of liver resections. Local recurrences can be managed with further ablation. Small tumour size, well-differentiated tumour and a reduced number of lesions are factors associated with good prognosis. Temporary occlusion of the portal venous and hepatic arterial flow may increase the size of ablation but the safety aspect requires further validation. MWA is a minimally invasive technique that has broadened the therapeutic option for patients with conventionally unresectable liver tumours with promising survival data. Future advances in the applicator design and treatment monitoring may further improve its efficacy and widen the indications.

Lessons from laparoscopic liver surgery: a nine-year case series.

OBJECTIVE: This series describes a developing experience in laparoscopic liver surgery presenting results from 40 procedures including right hemihepatectomy, left lateral lobectomy, and microwave ablation therapy. METHODS: Forty patients undergoing laparoscopic liver surgery between September 1997 and November 2006 were included. The data set includes: operative procedure and duration, intraoperative blood loss, conversion to open operation rates, length of hospital stay, complications, mortality, histology of lesions/resection margins, and disease recurrence. RESULTS: Mean age of patient: 59 years, 17/40 male, 23/40 female, 23/40 of lesions were benign, and 17/40 malignant. Operations included: laparoscopic anatomical resections n = 15, nonanatomical resections n = 11, microwave ablations n = 8 and deroofing of cysts n = 7. Median anaesthetic time: 120 minutes (range 40-240), mean blood loss 78 mL and 1/40 conversions to open. Median resection margins were 10 mm (range 1-14) and median length of stay 3 days (range 1-10). Operative and 30-day mortality were zero with no local disease recurrence. CONCLUSION: Laparoscopic liver surgery appears safe and effective and is associated with reduced hospital stay. Larger studies are required to confirm it is oncologically sound.

Rapid microwave ablation of large hepatocellular carcinoma in a high-risk patient.

A 74-year-old male with an inoperable, large (6 cm in diameter) primary hepatocellular carcinoma of the liver was successfully treated using a novel microwave ablating system. Using a single applicator, the tumour was treated at 150 W for 4 minutes. An ablation zone 8 cm in diameter was achieved, which gradually shrunk to form scar tissue that remained unchanged without tumour recurrence for 2 years.