Can 18F-FDG PET/CT findings be used to predict orbital tumor histology?

PURPOSE: To investigate whether 18F-FDG PET/CT might be useful to predict the histology of various orbital tumors based on the maximum standard uptake value (SUVmax) and the OMSUV (orbital max SUV)/MLSUV (mean liver SUV) ratio. PATIENTS AND METHODS: A retrospective single-center study was conducted between May 2019 and December 2020. Patients with an orbital mass who underwent preoperative 18F-FDG PET/CT followed by an orbital biopsy were included. Tumor histology was classified as follows: orbital inflammation, solid tumor, low-grade lymphoid tumor, and high-grade lymphoid tumor. Orbital tumors were also classified as indolent or aggressive. Data recorded included the orbital SUVmax, OMSUV/MLSUV ratio and additional extra-orbital SUV sites. RESULTS: Forty-five patients (24 men) were included. There were 15 (33.3%), 14 (31.1%), 9 (20%), and 7 (15.5%) cases of orbital inflammation, solid tumor, low-grade lymphoid tumor, and high-grade lymphoid tumor, respectively. No correlation was found between the OMSUV/MLSUV ratio and orbital SUVmax and tumor histology (Z = -0.77, Z = -0.6, Z = -1.6, and Z = 0.94, all P > 0.05, respectively). No correlation was found between the OMSUV/MLSUV ratio (Z = -1.42, P > 0.05) and orbital SUVmax (Z = -0.82, P > 0.05) and tumor aggressiveness (indolent versus aggressive). Subgroup analyses showed that SUVmax was predictive of lymphoma aggressiveness (P = 0.05) and was able to distinguish orbital cancers (all lymphomas+solid tumors) from benign tumors (P = 0.02). CONCLUSION: 18F-FDG PET/CT could not be used to predict the underlying orbital tumor histology. However, more aggressive tumors, especially high-grade lymphomas and cancers, tended to have a higher orbital SUVmax compared to indolent lesions.

Efficacy and safety of an artificial dermal graft for the reconstruction of exenterated sockets: a preliminary report.

PURPOSE: The purpose of this study is to report our experience with the use of artificial dermis grafts for orbital socket reconstruction following orbital exenteration (OE). METHOD: A retrospective study was conducted in our ocular oncology centre from May 2018 to June 2020 in patients undergoing OE for orbital malignancies in whom an artificial dermis device (Integra® template, 2 layers) was used for reconstruction. Data recorded included demographics, previous and adjuvant treatments, aetiologies, surgical procedure, surgical reconstruction, complications and follow-up. The main outcome measure was the time between OE and the full granulation of the cavity. RESULTS: Ten patients (mean age, 71.3 years [43-92]) were included. Tumours originated from the conjunctiva (n = 5, 50%), eyelid (n = 3, 30%) and orbit (n = 2, 20%). Nine patients underwent total OE, and one required enlarged OE. Orbital reconstruction was performed using an artificial dermis alone (n = 9, 90%) or combined with regional flaps (n = 1, 10%). The mean granulation time was 3.3 weeks (2-4). Three (30%) patients received adjuvant radiotherapy 1 month post-surgery. The mean time to spontaneous epithelialization was 9.4 weeks (6-12). Preoperative and postoperative radiotherapy was not associated with a delayed epithelialization of the socket (p = 0.463 and p = 0.236, respectively). One (10%) and 2 (20%) patients experienced postoperative socket infection and an ethmoidal fistula, respectively. The mean follow-up was 11.6 months (6-16). CONCLUSION: Using artificial dermis grafts alone or with regional flaps appears to be a viable surgical procedure for orbital socket reconstruction. They reduce surgical morbidity and hospital stay. Preoperative and postoperative radiotherapy does not seem to delay socket healing.