Groin dissection was performed in 151 consecutive patients from 1970 to 1984. Groin dissections were therapeutic in 138 cases (91%) and elective in 13 (9%). One hundred forty-three patients (95%) underwent an ilioinguinal node dissection, while eight (5%) were treated with an inguinal node dissection. In 88 patients, the groin dissection was combined with isolated regional perfusion. Primary wound closure was performed in 140 patients (93%). There was no 30-day postoperative mortality. Complications included temporary seroma (26 [17%] of 151 patients), wound infection (14 patients [9%]), wound necrosis (five patients [3%]), and edema (30 patients [20%]). Residual inguinal node metastases after groin dissection did not occur. Morbidity of groin dissection did not increase when the groin dissection was combined with isolated regional perfusion. Quantification of the degree of edema in 66 patients revealed functional limitation due to edema in three patients (4.5%). This technique of groin dissection gives good results with minimal functional morbidity of the affected leg.

The viability of cells present in waste products originating during CO2-laser evaporation of Cloudman S91 mouse melanomas was investigated. Cytologic smears showed mainly carbonized particles and thermally damaged cells but some morphologically intact cells as well. Viability was tested with the trypan blue test, by in vitro culture and intramuscular and intraperitoneal inoculations in syngeneic mice. No dye-excluding cells were found in the trypan blue test. Growth was noted neither in vitro nor in vivo in the 127 mice, intramuscularly or intraperitoneally injected with 10(5) x 10(5)/10 microliter smoke or debris particles, and killed four weeks after inoculation. Viable tumor cells, derived from a Cloudman melanoma cell line and added to the smoke and debris suspensions, remained viable. Thus, a toxic influence of smoke and debris particles in viable tumor cells, which would make the viability tests meaningless, was excluded. It is highly unlikely that viable tumor cells do occur in the waste products of CO2-laser tumor vaporization.

Twenty-five patients with nonseminomatous testicular tumors stages IIB and IIC were treated at the Groningen University Hospital between January 1978 and April 1983. One patient died from his extensive tumor during chemotherapy. The remaining 24, treated by combination chemotherapy with cisplatin, vinblastine, and bleomycin as well as by surgery, are all alive after a mean follow-up period of 56 months. A laparotomy was performed after chemotherapy in each of the 24 cases. In four patients no residual tumor was found. Residual tumor was resected in 20 patients, in 13 the tumor contained only necrosis and fibrosis, 7 had mature teratoma. Comparison of the histologic features of the primary testicular tumor with those of the retroperitoneal residual tumor after chemotherapy, revealed that if the primary tumor did not contain a teratoma component the residual tumor showed only necrosis and/or fibrosis. When the primary tumor contained a teratoma component, mature teratoma was found in 50% (7/14) of the residual tumors.

Investigating the mechanisms underlying maturation of metastases of nonseminomatous germ cell tumors on administration, of chemotherapy, the histologic characteristics of primary testis tumors was compared to the histologic characteristics of their retroperitoneal metastases in three historical patient groups. The metastases in Group I (20 patients) were not treated; those in Groups II (nine patients) and III (24 patients) were treated, respectively, with three cycles of dactinomycin and with four cycles of cis‐diammine‐dichloroplatinum, vinblastine, and bleomycin, before retroperitoneal lymph node dissection. In Group III there was a significant increase of metastases consisting of differentiated teratoma only, as compared to the metastases of Group I. However, both with and without chemotherapy, the metastases contained fewer areas of differentiated teratoma than the primary lesions. Metastases containing differentiated teratoma with and without other components, with one exception in Group III, were derived from primary tumors containing mature areas as well. Components other than mature teratoma were almost completely eradicated in Group III. These findings strongly suggest that selective destruction of components other than differentiated teratoma causes the mature histologic characteristics in the metastases upon administration of chemotherapy. The results do not support the hypothesis of induction of differentiation by the chemotherapeutic agents.

Reconstruction of the hip joint by a saddle prosthesis after excision of a malignant pelvic tumor is a relatively new method, which thus far has been mainly used for revision of infected hip arthroplasties. One patient with a metastatic cystosarcoma phyllodes and one patient with a chondrosarcoma of the pelvis were treated by local resection and reconstruction with a saddle prosthesis. Although the patient with the metastatic cystosarcoma phyllodes died 9 months after surgery due to metastatic disease, both patients had early recovery, with no difference in leg length and obtained early painless complete weight bearing with satisfactory functional result. These two case reports clearly illustrate the usefulness of the saddle prostheses in limb saving surgery for malignant tumors of the pelvis.