Active specific immunotherapy with vaccinia melanoma oncolysate.

Based on antitumor effects observed with vaccinia virus infected tumor cell lysate in animal models, adjuvant immunotherapeutic clinical trials were undertaken in patients with melanoma using vaccinia virus infected melanoma oncolysate (VMO). Preliminary clinical trials showed that the VMO is safe except minimal side effects such as mild fever, pain, and tenderness at the site of VMO injection, and mild lymphadenopathy. The effective dose of VMO was investigated in a following trial using 0.05 to 2.0 mg doses of VMO. Clinical responses and laboratory monitoring of melanoma-specific antibody responses decided the 2 mg dose of VMO is optimal for future trials. In all the clinical trials, patients showed moderate responses and their postimmune sera contained melanoma-specific antibodies. In a Phase II clinical trial completed August 1985 19 of 39 stage II patients had a disease-free mean survival time of 24.6 months, statistically significant compared with historical controls. Because of compelling evidence of significant clinical responses in patients treated with VMO adjuvant immunotherapy in the Phase II trial, a prospective randomized multi-institutional double-blind Phase III adjuvant VMO immunotherapeutic trial using adjuvant therapy of vaccinia virus alone as control, was recently initiated. Results of this trial are anxiously anticipated.

Laparoscopically assisted resection of a colonic lipoma.

Laparoscopic excision of a lipoma of the sigmoid colon is described. The patient's postoperative recovery was rapid and similar to that experienced in patients undergoing laparoscopic cholecystectomy and appendectomy. He enjoyed the benefit of complete surgical excision of his disease while foregoing the postoperative discomfort and morbidity of open celiotomy. Because the majority of lipomas are submucosal, endoscopic removal carries an inherently high risk. For those lesions amenable to it, laparoscopic colotomy and excision offers a viable alternative to open laparotomy excision of colonic lipomas and polyps in general.

Laparoscopic-assisted excision of a solitary cecal ulcer.

Laparoscopic-assisted excision of a solitary cecal ulcer that presented with right lower quadrant pain in a 61-year-old male is described. The patient benefited from complete surgical excision of his disease and he experienced a rapid postoperative recovery similar to that of other laparoscopic procedures, while foregoing the postoperative discomfort and morbidity associated with celiotomy. Excision of a complicated, benign cecal ulcer requires minimal bowel resection and is particularly amenable to laparoscopic assistance for minimally invasive access. For cecal ulcers requiring operative intervention, laparoscopy offers an alternative to open celiotomy.

Therapeutic effect of a vaccinia colon oncolysate prepared with interleukin-2-gene encoded vaccinia virus studied in a syngeneic CC-36 murine colon hepatic metastasis model.

Vaccinia CC-36 murine colon oncolysate (VCO) prepared with interleukin-2-gene encoded recombinant vaccinia virus (IL-2VCO) was used in the treatment of a syngeneic murine colon adenocarcinoma (CC-36) hepatic metastasis to test the beneficial effect of the interleukin-2-gene encoded vaccinia virus over a control recombinant vaccinia virus in producing a vaccinia oncolysate tumor cell vaccine. Results suggest that the IL-2VCO treatment significantly reduced the hepatic tumor burden in comparison with the controls that received either IL-2-gene-encoded recombinant vaccinia virus or a plain recombinant vaccinia virus or vaccinia oncolysate prepared with the plain recombinant virus. The survival of mice treated with IL-2VCO was also improved in comparison with mice treated with other preparations. The induction of a cytolytic T lymphocyte response was examined to elucidate the mechanism of the induction of antitumor responses in IL-2VCO-treated mice. Fresh peripheral blood lymphocytes (PBL) isolated from IL-2VCO-treated mice showed a higher cytolytic activity against CC-36 tumor cell target when compared to PBL from the mice of other treatment groups, suggesting that the IL-2VCO induced an antitumor cytolytic T lymphocyte response. These results suggest that a vaccinia oncolysate, prepared with recombinant vaccinia virus encoding an immunomodulating cytokine gene will enhance antitumor responses in the host.

Active specific adjuvant immunotherapy with vaccinia melanoma oncolysate.

Vaccinia melanoma oncolysate is an investigative agent for active specific adjuvant immunotherapy. Viral oncolysate work in animals has led to application of this treatment in humans. Success of initial trials in treatment of melanoma has led to a phase III randomized, prospective, double-blind, multi-institutional trial, which is currently under way.

Prospects for gene therapy and lymphokine therapy for metastatic melanoma.

Conventional treatment of cancer, especially for patients with metastatic melanoma tumor, is often ineffective. Immunotherapy and recently introduced gene therapy have revolutionized the treatments of patients with metastatic melanoma tumor. Use of biological response modifiers, such as interleukins and interferons, have been found to enhance therapeutic benefits to patients with malignant melanoma. Initial studies with a high-dose interleukin-2 (IL-2) therapy have proved effective in patients with melanoma tumor, although a variety of systemic toxicities were observed. A low-dose IL-2 continuous infusion has shown a similar response in patients with melanoma tumor, but produced lesser toxicity. The low-dose IL-2 therapy has been studied with an adoptive transfer combined with either autologous lymphokine activated killer cells or autologous tumor infiltrating lymphocytes (TIL). IL-2 in combination with chemotherapeutic agents such as flavone acetic acid, dacarbazine, and cyclophosphamide have also been studied in patients with metastatic melanoma. Results have shown a moderate response in patients with metastatic melanoma. TIL therapy, however, has been shown to result in higher objective regression due to potent tumor-specific killing and tumor-specific targeting characters of the TIL. The tumor targeting nature of the TIL creates the possibility of using TIL as a vehicle to deliver gene product specifically to tumor tissue. Safety and toxicity of gene-transduced TIL were addressed by the use of neomycin-resistant, gene-transduced TIL in patients with metastatic melanoma. We also investigated the use of vaccinia oncolysate therapy by using the viral oncolysate prepared with IL-2 gene encoded vaccinia virus. Preliminary studies with murine hepatic metastases colon model have shown encouraging results.

Laparoscopic-assisted bowel surgery.

The use of laparoscopic surgical techniques is now being applied to a variety of operations traditionally performed in an open fashion. Twenty patients underwent laparoscopic-guided large and small bowel surgery at our institution from March 1991 to April 1992. The indications for surgery included polyps, obstruction, bleeding, and perforation, and pathologic diagnoses included benign polyps, lipomas, inflammatory bowel disease, perforation of a jejunal diverticulum, colonic arteriovenous malformations, and adenocarcinoma. Mobilization of the colon, ligation of the mesentery, and closure of the mesenteric defect were performed using the laparoscopic equipment. One trocar site was enlarged to 3 cm to deliver the bowel through the abdominal wall. All anastomoses were hand-sewn. Postoperative hospitalization ranged from 2 to 31 days (median, five days). No mortality was noted, and morbidity was 20 percent. We conclude that laparoscopic-guided bowel surgery is technically feasible and should translate into shorter hospitalization and less patient discomfort.