Detection of occult melanoma by preoperative positron emission tomography-computed tomography and intraoperative ultrasonography

Navigation-assisted localisation and resection of subclinical metastatic malignant melanoma of unknown primary based on 18-fluorodeoxyglcose positron emission tomography computed tomography fusion imaging

A technical application using a stereotactic navigation system with fusion images of [18F]-2-fluorodeoxyglucose (FDG) positron tomography and computed tomography (PET-CT) in the case of a metastatic melanoma of unknown primary site is described. A 50-year-old woman presented with a slow, growing level V neck lump which was cytologically proved to be a metastatic melanoma despite the absence of prior or existing history of skin malignancy. Whilst detailed physical examination failed to yield the site of the primary lesion, full body FDG-PET images isolated FDG-avid subclinical scalp lesions. Fused PET-CT data provided the navigation system with accurate localisation of the subclinical metastatic lesion. Histopathological examination of the navigation-guided resection specimen confirmed that the lesion was excised with acceptable margins. This case illustrates the feasibility of navigation-assisted resection of a subclinical malignant melanoma lesion and may have a role to play in the management of the melanoma of unknown primary.

Intraoperative ultrasound assistance for excision of impalpable musculoskeletal soft tissue tumors

Intraoperative ultrasonography is a useful tool for the detection and extirpation of liver metastases, breast masses, and melanoma. However, the efficacy of this technology in intraoperative localization and resection of small soft tissue tumors has not been addressed. The purpose of this study is to report on the efficacy of intraoperative ultrasound assistance in excising impalpable musculoskeletal soft tissue tumors. Twenty-two soft tissue tumors <3 cm (range, 0.7-3 cm) were resected with intraoperative ultrasound assistance. All tumors were localized in the deep panniculus, fascia, or muscle. Surgical time and length of incisions was recorded in all the cases. Intra- and postoperative reregistration was made to confirm the tumor resection. Ultrasound assistance was successful in obtaining an accurate localization in all treated cases. Mean surgical time was 30 minutes (range, 13-87 minutes). Average incision length was 5.7 cm (range, 2.5-10.6 cm). Reregistration allowed intraoperative confirmation of the adequacy of the excision. The procedure allowed recognized and excised additional nodules not previously diagnosed in 3 cases. Postoperative echography done in all patients confirmed complete extirpation of the tumors, and histopathology confirmed adequate margins obtained. Intraoperative ultrasound can be used as an efficient tool to localize and treat impalpable small soft tissue tumors.

The use of intraoperative PET probe to resect metastatic melanoma

Two cases of metastatic melanoma resected with assistance of an intraoperative handheld positron emission tomography (PET) probe are reported. The PET probe is increasingly being used to complement findings made during surveillance monitoring. In qualified surgical candidates metastectomy may completely remove tumour burden on the patient. Two women, one 46-year-old and another 38-year-old, presented with recurrence after having initial exploration for melanoma surgical staging performed either at the University of California, San Francisco (UCSF) or at outside institutions. Combined PET/CT scans were performed preoperatively for each patient, and the use of the PET handheld probe during surgery aided the detection of the previously undetected metastases. Neither patient suffered perioperative complications.