Here we performed single-stage laparoscopic surgery for several bilateral multifocal lesions. We approached the bilateral organ tumors by installing a GelPOINT in the navel at the center of the body’s surface. Hachisuka et al. reported that the ZI method is indicated for use in the umbilical region [
5]. RPLS with a ZI was especially useful in Case 1 because it allowed the use of a shorter incision with the flexural forceps that allowed extraction of the spleen or lumen organs, such as part of the resected colon. However, a large organ, such as one > 70 mm affected by RCC, is difficult to extract from the original incision and would require an additional incision. We completed the operations safely in both cases using single-stage surgery. Nephrectomy required 123 min in Case 1 and 177 min in Case 2, which seem not so long compared to other reports [
6]. Furthermore, the common incision for the bilateral lesions was only a skin incision and other surgical procedures do not shorten the total operating time because they require separate delamination and incision. Considering that it was necessary to change the patients’ positions for the bilateral tumors, the total operating time was acceptable. The perioperative courses in both case series were uneventful except for two units of blood transfused postoperatively in Case 2. When there is little perioperative bleeding, a drain tube may not be necessary. Experience with more cases and improvements in laparoscopic skills are necessary, but our proposed procedure may be a reasonable approach for the management of bilateral organ tumors. The shorter the total incision length, the less prolonged the postoperative ileus [
7]. Walz et al. reported that single foramen surgery was superior to conventional multi-port surgery for adrenalectomies in terms of postoperative analgesic frequency and hospitalization period [
8]. Our cases involved the complexities of multiple bilateral lesions. Nonetheless, in Case 2, which had the most ports (six), the total incision length was 99 mm, the same as that in conventional laparoscopic nephrectomy.
The ZI method was originally developed to make surgical wounds less noticeable. Figure
4 shows the condition of the umbilical region in the first and sixth postoperative months for this case series. An additional incision was required in Case 2 to enable extraction of the specimens (Fig.
4, below). Therefore, the umbilical scar of Case 2 was more obvious than that in Case 1. However, it can be confirmed that the scar of the additional incision site in Case 2 at 6 months postoperative is becoming less noticeable. The limitation of a ZI is that some cases require additional incisions. We could not make incisions along the circumference of the umbilicus; rather, they were made to both ends of the linear incisions. We designed the upper or lower half of the incision at the beginning of the surgery and then created the additional incision based on the requirement for specimen extraction. From a cosmetic standpoint, it is necessary to use a more refined ZI method that considers specimen size and skin striae direction. Furthermore, in order to prove the superiority of these procedures, a larger clinical trial using a quantitative evaluation method such as Derriford Appearance Scale (DAS 59) should be necessary [
9].