In this study, we reported the surgical outcome of 126 patients with adnexal tumors ≥ 10 cm (mean of 15.08 ± 5.03 cm; maximum of 30 cm), among whom only one required conversion to open surgery. These results suggest the feasibility of laparoscopic management of adnexal masses ≥ 10 cm. In another study on 77 women with ovarian cysts ≥ 10 cm, conversion to open was required in four patients (12), which is higher than that of ours. This difference could be due to the difference in the experience of the laparoscopic surgeon and the difference in the rate of intra-operative complications between the studies. Among 19 patients, in the study by Vlahos et al. who had adnexal mass with a mean diameter of 8.3 cm, there were no cases of conversion to open (13). The difference between the results of this study and that of ours could be due to the small sample size of their study, but this study also confirms the results of the present study, considering the low risk of conversion to open surgery in large adnexal masses.
One of the important factors against the suggestion of laparoscopic surgery for large adnexal masses is the risk of rupture and its negative effect on patients’ outcomes (7, 8). However, in our study, incidental rupture was only observed in 8 patients, two of whom were malignant. These results show that the laparoscopic method has an acceptable rate of cyst rupture. In another study by Shiota et al., comparison of 1483 cases of benign ovarian cysts according to the cyst size showed no difference in the incidence of cyst rupture among patients with cyst size < 5 cm, 5-10cm, and > 10 cm (14), which confirm the results of the present study. In another study by Detorakis et al., studying the surgical outcome of 102 women with adnexal cysts with mean size of 5.7 cm (2.3–10.5 cm) showed cyst rupture in 31.8% of the patients and 7.2% in masses > 8 cm (15). These authors concluded that laparotomy is the preferred method for large adnexal masses, but generally speaking, iatrogenic or accidental rupture and spillage of the adnexal mass contents are considered an inevitable incidence during surgery and may occur both in laparoscopic and laparotomic approaches (4). Furthermore, the prognostic value of significant spillage in malignant cases is still controversial and some suggest that laparoscopic treatment of ovarian cancer does not have a higher risk of spillage (16). Therefore, we believe that the risk of rupture should not ban surgeons from the choice of laparoscopy, considering the other advantages of this method. With the availability of frozen sections at many tertiary centers and adherence to proper surgical techniques, the chance of spreading malignancy has been reduced considerably.
Another important surgical complication is the bleeding volume during surgery and requirement of blood transfusion and the results showed that the mean bleeding volume of the studied patients was 124.61 ± 287.32 cc and only five patients required blood transfusion. In another study by Demir et al, the results showed that 97.8% of women with adnexal masses of 8-13cm treated with laparoscopy had blood loss < 200 cc (9). These results confirm that of the present study on the low bleeding in laparoscopic treatment of large adnexal masses, considered one of the important advantages of laparoscopy vs. laparotomy (17, 18). The mean operation time was 128.88 ± 63.37 minutes in our study. In the study by Vlahos et al on 53 women with adnexal masses of all sizes, undergoing laparoscopy, the mean operative time was 45 minutes (13), which is much less than that of the present study. In the study by Demir et al., 97.92% of surgeries lasted < 136 minutes (9), which is similar to the results of the present study. But they have only evaluated patients with benign type, while we included patients with any pathologic type. In the study by Machida et al. comparison of the median operation time was significantly higher in cases with adnexal masses > 10 cm vs. <5 cm (73 vs. 59 minutes) (11). These results suggest that large adnexal masses can prolong the surgical duration, which is justifiable by the technical difficulty of laparoscopy in large masses, considered one of the disadvantages of this approach for these cases. However, the results of our study showed that the risk of surgical complications are not much, when patients are selected after complete physical examination, precise imaging studies, and measurement of tumor markers. Furthermore, all surgeries were carried out by a single surgeon; in the meantime, a multidisciplinary team of experts consisting of pathologists, oncologists, colorectal surgeons, and urologists were involved and ready to be called on when necessary. As suggested, the risk of surgical complications is not predicted by the tumor size (11). Therefore, it does not seem logical to impose patients to the critical risk of invasive open surgeries, especially in cases with benign pathologies. The maximum tumor size for safe laparoscopic approach is yet to be determined, as 10 cm threshold seems questionable.
The incidence rate of incidental finding of ovarian cancer during laparoscopy has been reported to be between 0.65% and 0.9% of premenopausal women and 3% of postmenopausal women (19). In our study, there were 15 patients with malignancy or metastasis, five of whom (33.3%) were postmenopausal. Other studies have reported other incidence rates for malignant ovarian mass (4, 9, 12), which can vary based on the frequency of malignancy in the study place and based on the inclusion criteria of the study. The results showed that patients with malignancy or metastasis were significantly older and had a longer duration of surgery and intra-operative complications. These results are consistent with the results of the study by Gad et al, which reported higher rate of complications and longer operative time in patients with borderline/malignant adnexal mass, compared to benign group undergoing laparoscopic treatment (20). Furthermore, they reported higher rate of conversion to open, blood loss, and duration of hospital stay (20), which was not observed in our study. Other studies have also confirmed the superiority of laparoscopy vs. laparotomy for treatment of ovarian cancers (21, 22), as well as comparable accuracy of staging of laparoscopy vs. laparotomy and comparable survival rates (23, 24), while the results of the present study suggested higher complication rates in large tumors. Due to the small sample size of this subgroup in our study, further studies should be performed to investigate the applicability of laparoscopy in large adnexal malignant tumors.
Our study had some limitations. The first limitation was the cross sectional nature of this study, which limited suggestion of causal relationship between the study variables. Furthermore, we did not follow patients to study the long term results and did not evaluate the survival or recurrence rate in the studied population. The small sample of the study, especially in subgroups, was another limitation of the present study.