first-in-human safety study of laser tissue welding for surtureless laparoscopic partial nephrectomy

Conditions: Benign Renal Tumors; Malignant Renal Tumors

Summary: the objective of this pilot study will be to obtain a clinical safety and efficacy endpoint profile of laser tissue welding therapy for sealing the resected kidney surface after laparoscopic partial nephrectomy required for removal of resectable benign or malignant renal tumors in 10 patients.

scientific rationale: the use of partial nephrectomy to treat small newly diagnosed kidney tumors is vastly under-used as per nci statistics (http://www.cancer.gov/cancertopics/treatment/partial-nephrectomy0208). as per the surveillance, epidemiology and end results (seer) program, (http://seer.cancer.gov/statfacts/html/kidrp.html), the prevalence of cancer of the kidney and renal pelvis is 296,074 while the estimated new cases are 46,410 and deaths 13,040 in the united states in 2010 (www.cancer.gov/cancertopics/types/kidney). there has been an increase in detection of incidental small renal mass (≤ 4cm) cases (tnm staging t1a) due to widespread use of ultrasound and abdominal cross sectional imaging (ct, mri) and thus an increase in the amount of renal surgery performed. current surgical practice for nephron sparing surgery allows at least 1 cm margin of normal tissue around the tumor3. this is the stage when curative resections are possible. during a partial nephrectomy, the renal artery is clamped to minimize bleeding while resecting the tumor. since a major reconstruction is required with suturing, clamp time can be significant, anywhere between 15 and 45 minutes. it has been repeatedly shown that reducing clamp time preserves renal function and that there is significant damage to the kidney if the renal artery is clamped for more than 30 minutes. this is especially crucial when dealing with patients with hypertension, diabetes, chronic renal failure or a tumor in a single kidney. extended clamp time can result in decreased renal function and ultimately the need for dialysis at some point. because of the inherent difficulties of laparoscopic suturing, this has not been widely used particularly in view of the risk of prolonged warm ischemia time. many patients therefore undergo a radical nephrectomy instead of a nephron sparing procedure. hemorrhage 9.5% (1) , is the major complication following partial nephrectomy. besides bleeding (1) urinary fistula (4.5%), ureteral obstruction, and renal insufficiency due to prolonged warm ischemia times are further complications of partial nephrectomy. laser tissue welding is the first combination (laser and biologic) class iii surgical device intended to join and seal tissues accurately and instantly. the treatment process uses thermal energy created when a laser excites photosensitive dye molecules, to coagulate the protein albumin which transforms from a liquid to a solid instantly. laser tissue welding creates a non-compressive, non-ablative sealing of tissues with microscopic thermal damage. this combination of a laser with albumin biologics stops bleeding and fluid leaks in nanoseconds without using sutures, hemostatic clotting factors (platelets/thrombin/fibrin), thermal or cryoablation. (video: http://www.lasertissuewelding.com/application.aspx?aid=8)

Eligibility criteria:
inclusion criteria: 1. t1a (\< 4 cm). all resectable benign, primary or secondary malignant tumors of one kidney. no bi-lateral disease. 2. serum creatinine: ≤ 2.5 mg/dl 3. glomerular filtration rate greater than ≥ 50 ml/min/m2 4. platelet count ≥ 50,000/mm3 5. prothrombin time \< 18 seconds 6. partial thromboplastin time (ptt) ≤ 1.5 times control 7. serum albumin levels \> 3g/dl (normal range 3.5 to 5 g/dl) exclusion criteria: 1. age younger than 18 years old 2. severe uncorrected hypertension 3. uncorrectable coagulopathies 4. pregnancy 5. active urinary tract infection 6. t1b (\>4 cm) lesion and above 7. systemic or local infection 8. subject has known allergy or intolerance to iodine or human serum albumin 9. recent febrile illness that precludes or delays participation pre-operatively 10. treatment with another investigational drug or other intervention during the study and follow-up period.

Keywords: laparoscopic partial nephrectomy surgical hemostasis laser tissue welding tissue sealant