Comparison of two hybrid sentinel node tracers: indocyanine green (ICG)-99mTc-nanocolloid vs. ICG-99mTc-nanoscan from a nuclear medicine and surgical perspective.

BACKGROUND: Lymph node (LN) metastasis is a relevant predictor for survival in patients with a.o. penile cancer (PeCa), malignant melanoma. The sentinel node (SN) procedure comprises targeted resection of the first tumour-draining SNs. Here, the hybrid tracer indocyanine green (ICG)-99mTc-nanocolloid has been used for several years to combine optical and nuclear detection. Recently, the resource of the nanocolloid precursor stopped production and the precursor was replaced by a different but chemically comparable colloid, nanoscan. Our aim was to study the performance of ICG-99mTc-nanoscan compared to ICG-99mTc-nanocolloid from a nuclear and surgical perspective. METHODS: Twenty-four patients with either PeCa or head-and-neck (H&N) melanoma and scheduled for a SN procedure were included. The initial group (n = 11) received ICG-99mTc-nanocolloid until no longer available; the second group (n = 13) received ICG-99mTc-nanoscan. Tracer uptake was assessed on lymphoscintigraphy and single-photon emission (SPECT). Intraoperatively, SNs were identified using gamma tracing and fluorescence imaging. Ex vivo (back-table) measurements were conducted to quantify the fluorescence emissions. Chemical analysis was performed to compare the ICG assembly on both precursors. RESULTS: The mean tracer uptake in the SNs was similar for ICG-99mTc-nanocolloid (2.2 ± 4.3%ID) and ICG-99mTc-nanoscan (1.8 ± 2.6%ID; p = 0.68). 3 SNs (interquartile range (IQR) 3-4) were detected on lymphoscintigraphy in PeCa patients receiving ICG-99mTc-nanoscan compared to 2 SNs (IQR 2-3) in PeCa patients receiving ICG-99mTc-nanocolloid (p = 0.045), no differences were observed in H&N patients. Back-table measurements of resected SNs revealed a lower total fluorescence intensity in the ICG-99mTc-nanoscan group (24*109 arbitrary units (A.U) IQR 1.6*109-14*109 in the ICG-99mTc-nanocolloid group versus 4.6*109 A.U. IQR 2.4*109-42*109 in the ICG-99mTc-nanoscan group, p = 0.0054). This was consistent with a larger degree of "stacked" ICG observed in the nanoscan formulation. No tracer-related adverse events were reported. CONCLUSIONS: Based on this retrospective analysis, we can conclude that ICG-99mTc-nanoscan has similar capacity for SN identification as ICG-99mTc-nanocolloid and can safely be implemented in SN procedures.

Mapping of sentinel lymph node drainage using SPECT/CT to tailor elective nodal irradiation in head and neck cancer patients (SUSPECT-2): a single-center prospective trial.

BACKGROUND: The majority of patients with head and neck squamous cell carcinoma (HNSCC) receive bilateral elective nodal irradiation (ENI), in order to reduce the risk of regional failure. Bilateral ENI, as compared to unilateral ENI, is associated with higher incidence of acute and late radiation-induced toxicity with subsequent deterioration of quality of life. Increasing evidence that the incidence of contralateral regional failure (cRF) in lateralized HNSCC is very low (< 10%) suggests that it can be justified to treat selected patients unilaterally. This trial aims to minimize the proportion of patients that undergo bilateral ENI, by using lymph drainage mapping by SPECT/CT to select patients with a minimal risk of contralateral nodal failure for unilateral elective nodal irradiation. METHODS: In this one-armed, single-center prospective trial, patients with primary T1-4 N0-2b HNSCC of the oral cavity, oropharynx, larynx (except T1 glottic) or hypopharynx, not extending beyond the midline and planned for primary (chemo) radiotherapy, are eligible. After 99mTc-nanocolloid tracer injection in and around the tumor, lymphatic drainage is visualized using SPECT/CT. In case of contralateral lymph drainage, a contralateral sentinel node procedure is performed on the same day. Patients without contralateral lymph drainage, and patients with contralateral drainage but without pathologic involvement of any removed contralateral sentinel nodes, receive unilateral ENI. Only when tumor cells are found in a contralateral sentinel node the patient will be treated with bilateral ENI. The primary endpoint is cumulative incidence of cRF at 1 and 2 years after treatment. Secondary endpoints are radiation-related toxicity and quality of life. The removed lymph nodes will be studied to determine the prevalence of occult metastatic disease in contralateral sentinel nodes. DISCUSSION: This single-center prospective trial aims to reduce the incidence and duration of radiation-related toxicities and improve quality of life of HNSCC patients, by using lymph drainage mapping by SPECT/CT to select patients with a minimal risk of contralateral nodal failure for unilateral elective nodal irradiation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03968679, date of registration: May 30, 2019.

Feasibility of Salvage Selective Neck Dissection after Primary Irradiation of Pharyngeal and Laryngeal Carcinoma.

INTRODUCTION: The concept of neck dissection (ND) in the management armamentarium of head and neck squamous cell carcinoma has evolved throughout the years. Nowadays, ND becomes more functional. METHODOLOGY: A retrospective study of 865 patients was performed at Netherlands Cancer Institute-Antoni Van Leeuwenhoek Hospital to investigate the feasibility of selective ND (SND). All patients with squamous cell carcinoma of the pharynx and larynx who received primary radiation and underwent salvage ND were included in the study. RESULT: A total of 29 NDs were analyzed. In 17 neck sides, viable metastases were found (58%), whereas in the other 12 specimens there were no viable metastases. In 16 of the 17 necks (94%), the metastases were located either in level II, III, or IV or in a combination of these 3 levels. Level V was involved in only 1 case (6%). CONCLUSION: It is well justified to perform a salvage SND (levels II, III, and IV) for pharyngeal and laryngeal carcinoma after primary radiation. In carefully selected cases of supraglottic and oropharyngeal carcinoma, a superselective ND also appears as an efficient option.

(Near-Infrared) Fluorescence-Guided Surgery Under Ambient Light Conditions: A Next Step to Embedment of the Technology in Clinical Routine.

BACKGROUND AND PURPOSE: In open surgery procedures, after temporarily dimming the lights in the operation theatre, the Photo Dynamic Eye (PDE) fluorescence camera has, amongst others, been used for fluorescence-guided sentinel node (SN) biopsy procedures. To improve the clinical utility and logistics of fluorescence-guided surgery, we developed and evaluated a prototype modified PDE (m-PDE) fluorescence camera system. METHODS: The m-PDE works under ambient light conditions and includes a white light mode and a pseudo-green-colored fluorescence mode (including a gray-scaled anatomical background). Twenty-seven patients scheduled for SN biopsy for (head and neck) melanoma (n = 16), oral cavity (n = 6), or penile (n = 5) cancer were included. The number and location of SNs were determined following an indocyanine green-(99m)Tc-nanocolloid injection and preoperative imaging. Intraoperatively, fluorescence guidance was used to visualize the SNs. The m-PDE and conventional PDE were compared head-to-head in a phantom study, and in seven patients. In the remaining 20 patients, only the m-PDE was evaluated. RESULTS: Phantom study: The m-PDE was superior over the conventional PDE, with a detection sensitivity of 1.20 × 10(-11) M (vs. 3.08 × 10(-9) M) ICG in human serum albumin. In the head-to-head clinical comparison (n = 7), the m-PDE was also superior: (i) SN visualization: 100 versus 81.4 %; (ii) transcutaneous SN visualization: 40.7 versus 22.2 %; and (iii) lymphatic duct visualization: 7.4 versus 0 %. Findings were further underlined in the 20 additionally included patients. CONCLUSION: The m-PDE enhanced fluorescence imaging properties compared with its predecessor, and provides a next step towards routine integration of real-time fluorescence guidance in open surgery.

Functional and aesthetic recontouring of free flap reconstructions of the head and neck region with microdebrider.

Free flaps have become standard of care for reconstruction of the head and neck defects following surgery. The bulkiness of the free flap reconstruction may cause aesthetically and functionally suboptimal results. Recontouring of the flaps with a microdebrider thinning the excessive subcutaneous fatty tissue provides an easy and safe solution to problems. In this article, we describe the recontouring technique with microdebrider in the light of aesthetic and functional examples.

mTHPC-mediated photodynamic therapy of early stage oral squamous cell carcinoma: a comparison to surgical treatment.

BACKGROUND: mTHPC-mediated photodynamic therapy (PDT) is used for treatment of early head and neck squamous cell carcinoma. This study is a retrospective comparison of PDT with transoral surgery in the treatment of early primary squamous cell carcinoma of the oral cavity/oropharynx. METHODS: PDT data were retrieved from four study databases; surgical results were retrieved from our institutional database. To select similar primary tumors, infiltration depth was restricted to 5 mm for the surgery group. A total of 126 T1 and 30 T2 tumors were included in the PDT group, and 58 T1 and 33 T2 tumors were included in the surgically treated group. RESULTS: Complete response rates with PDT and surgery were 86 and 76% for T1, respectively, and for T2 63 and 78%. Lower local disease-free survival for PDT compared to surgery was found. However, when comparing the need for local retreatment, no significant difference for T1 tumors was found, while for T2 tumors surgery resulted in significantly less need for local retreatment. No significant differences in overall survival between surgery and PDT were observed. CONCLUSIONS: PDT for T1 tumors results in a similar need for retreatment compared to surgery, while for T2 tumors PDT performs worse. Local disease-free survival for surgery is better than for PDT. This may be influenced by the benefit surgery has of having histology available. This allows an early decision on reintervention, while for PDT one has to follow a wait-and-see policy. Future prospective studies should compare efficacy as well as morbidity.

MR and CT based treatment planning for mTHPC mediated interstitial photodynamic therapy of head and neck cancer: description of the method.

BACKGROUND AND OBJECTIVE: Interstitial photodynamic therapy is a potentially important tool in the management of voluminous or deep-seated recurrent head and neck cancers. STUDY DESIGN/METHODS: The described treatment algorithm in this manuscript consists of the treatment simulation, implantation of light sources, verification, modification of the treatment plan if necessary, and illumination. The tumor is delineated on imaging sections (CT, MRI, and/or PET/CT) and the treatment is simulated by virtually introducing light sources to the tumor volume on specially modified brachytherapy software. This enables us to determine if the treatment is technically feasible, and information about approximate number and location of light sources necessary. Following implantation of catheters in which the light sources will be introduced, CT or MR scan is performed to verify the actual location of the implanted catheters. The verification-CT is imported to the software and co-registered with pre-treatment images to observe the deviations from the simulation. The simulation is run again with the actual position of the light sources to determine if any additional light sources are necessary and adaptation of the source length in order to cover the tumor volume (modification). Thereafter the tumor is illuminated. RESULTS: This method has the potential to help with identifying iPDT feasible patients by simulating before the actual treatment. The suboptimal placement of light sources can be identified and corrected. The simulations were documented and saved for subsequent evaluation of the technique. CONCLUSION: The proposed technique can help standardize and document iPDT.

A matched cohort comparison of mTHPC-mediated photodynamic therapy and trans-oral surgery of early stage oral cavity squamous cell cancer.

Photodynamic therapy (PDT) of early stage oral cavity tumors have been thoroughly reported. However, statistical comparison of PDT to the surgical treatment is not available in published literature. We have identified and matched cohorts of patients with early stage oral cavity cancers undergoing surgery (n = 43) and PDT (n = 55) from a single institute experience. The groups are matched demographically and had the same pre-treatment screening and follow-up schedule. Both groups consisted only of tumors thinner than 5 mm to ensure comparability. The endpoints were local disease free survival, disease free survival, overall survival and response to initial treatment. Local disease free survival at 5 years were 67 and 74 % for PDT and surgery groups, respectively [univariate HR = 1.9 (p = 0.26), multivariable HR = 2.7 (p = 0.13)]. Disease free survival at 5 years are 47 and 53 % for PDT and surgery groups, respectively [univariate HR = 0.8 (p = 0.52), multivariable HR = 0.75 (p = 0.45)]. Overall survival was 83 and 75 % for PDT and surgery groups, respectively [(univariate HR = 0.5 (p = 0.19), multivariable HR = 0.5 (p = 0.17)]. In the PDT group, six patients (11 %) and in the surgery group 11 patients (26 %) had to receive additional treatments after the initial. All of the tested parameters did not have statistical significant difference. Although there is probably a selection bias due to the non-randomized design, this study shows that PDT of early stage oral cavity cancer is comparable in terms of disease control and survival to trans-oral resection and can be offered as an alternative to surgical treatment.

Concomitant radio- and fluorescence-guided sentinel lymph node biopsy in squamous cell carcinoma of the oral cavity using ICG-(99m)Tc-nanocolloid.

PURPOSE: For oral cavity malignancies, sentinel lymph node (SLN) mapping is performed by injecting a radiocolloid around the primary tumour followed by lymphoscintigraphy. Surgically, SLNs can then be localized using a handheld gamma ray detection probe. The aim of this study was to evaluate the added value of intraoperative fluorescence imaging to the conventional radioguided procedure. For this we used indocyanine green (ICG)-(99m)Tc-nanocolloid, a hybrid tracer that is both radioactive and fluorescent. METHODS: Fourteen patients with oral cavity squamous cell carcinoma were peritumourally injected with ICG-(99m)Tc-nanocolloid. SLNs were preoperatively identified with lymphoscintigraphy followed by single photon emission computed tomography (SPECT)/CT for anatomical localization. During surgery, SLNs were detected with a handheld gamma ray detection probe and a handheld near-infrared fluorescence camera. Pre-incision and post-excision imaging with a portable gamma camera was performed to confirm complete removal of all SLNs. RESULTS: SLNs were preoperatively identified using the radioactive signature of ICG-(99m)Tc-nanocolloid. Intraoperatively, 43 SLNs could be localized and excised with combined radio- and fluorescence guidance. Additionally, in four patients, an SLN located close to the primary injection site (in three patients this SLN was located in level I) could only be intraoperatively localized using fluorescence imaging. Pathological analysis of the SLNs revealed a metastasis in one patient. CONCLUSION: Combined preoperative SLN identification and intraoperative radio- and fluorescence guidance during SLN biopsies for oral cavity cancer proved feasible using ICG-(99m)Tc-nanocolloid. The addition of fluorescence imaging was shown to be of particular value when SLNs were located in close proximity to the primary tumour.

A rare late complication after concomitant chemoradiation of an oropharyngeal tumor: cervical necrotizing fasciitis.

Chemoradiation is increasingly being used to treat locally advanced head and neck carcinomas. Possible rare complications of this treatment modality have begun to appear, as the number of treated patients increase. In this report, we present a case who underwent chemoradiation due to T3N3M0 tonsil cancer and developed necrotizing fasciitis of the neck at seven months following treatment. The patient recovered fully after treatment with surgical debridement with pectoralis major flap reconstruction and intravenous antibiotherapy.

Photodynamic therapy of early stage oral cavity and oropharynx neoplasms: an outcome analysis of 170 patients.

The indications of photodynamic therapy (PDT) of oral cavity and oropharynx neoplasms are not well defined. The main reason is that the success rates are not well established. The current paper analyzes our institutional experience of early stage oral cavity and oropharynx neoplasms (Tis-T2) to identify the success rates for each subgroup according to T stage, primary or non-primary treatment and subsites. In total, 170 patients with 226 lesions are treated with PDT. From these lesions, 95 are primary neoplasms, 131 were non-primaries (recurrences and multiple primaries). The overall response rate is 90.7% with a complete response rate of 70.8%. Subgroup analysis identified oral tongue, floor of mouth sites with more favorable outcome. PDT has more favorable results with certain subsites and with previously untreated lesions. However, PDT can find its place for treating lesions in previously treated areas with acceptable results.

Translation of c-Met Targeted Image-Guided Surgery Solutions in Oral Cavity Cancer-Initial Proof of Concept Data.

Intraoperative tumor identification (extension/margins/metastases) via receptor-specific targeting is one of the ultimate promises of fluorescence-guided surgery. The translation of fluorescent tracers that enable tumor visualization forms a critical component in the realization of this approach. Ex vivo assessment of surgical specimens after topical tracer application could help provide an intermediate step between preclinical evaluation and first-in-human trials. Here, the suitability of the c-Met receptor as a potential surgical target in oral cavity cancer was explored via topical ex vivo application of the fluorescent tracer EMI-137. Freshly excised tumor specimens obtained from ten patients with squamous cell carcinoma of the tongue were incubated with EMI-137 and imaged with a clinical-grade Cy5 prototype fluorescence camera. In-house developed image processing software allowed video-rate assessment of the tumor-to-background ratio (TBR). Fluorescence imaging results were related to standard pathological evaluation and c-MET immunohistochemistry. After incubation with EMI-137, 9/10 tumors were fluorescently illuminated. Immunohistochemistry revealed c-Met expression in all ten specimens. Non-visualization could be linked to a more deeply situated lesion. Tumor assessment was improved via video representation of the TBR (median TBR: 2.5 (range 1.8-3.1)). Ex vivo evaluation of tumor specimens suggests that c-Met is a possible candidate for fluorescence-guided surgery in oral cavity cancer.

Technologic (R)Evolution Leads to Detection of More Sentinel Nodes in Patients with Melanoma in the Head and Neck Region.

Sentinel lymph node (SN) biopsy (SNB) has proven to be a valuable tool for staging melanoma patients. Since its introduction in the early 1990s, this procedure has undergone several technologic refinements, including the introduction of SPECT/CT, as well as radioguidance and fluorescence guidance. The purpose of the current study was to evaluate the effect of this technologic evolution on SNB in the head and neck region. The primary endpoint was the false-negative (FN) rate. Secondary endpoints were number of harvested SNs, overall operation time, operation time per harvested SN, and postoperative complications. Methods: A retrospective database was queried for cutaneous head and neck melanoma patients who underwent SNB at The Netherlands Cancer Institute between 1993 and 2016. The implementation of new detection techniques was divided into 4 groups: 1993-2005, with preoperative lymphoscintigraphy and intraoperative use of both a γ-ray detection probe and patent blue (n = 30); 2006-2007, with addition of preoperative road maps based on SPECT/CT (n = 15); 2008-2009, with intraoperative use of a portable γ-camera (n = 40); and 2010-2016, with addition of near-infrared fluorescence guidance (n = 192). Results: In total, 277 patients were included. At least 1 SN was identified in all patients. A tumor-positive SN was found in 59 patients (21.3%): 10 in group 1 (33.3%), 3 in group 2 (20.0%), 6 in group 3 (15.0%), and 40 in group 4 (20.8%). Regional recurrences in patients with tumor-negative SNs resulted in an overall FN rate of 11.9% (group 1, 16.7%; group 2, 0%; group 3, 14.3%; group 4, 11.1%). The number of harvested nodes increased with advancing technologies (P = 0.003), whereas Breslow thickness and operation time per harvested SN decreased (P = 0.003 and P = 0.017, respectively). There was no significant difference in percentage of tumor-positive SNs, overall operation time, and complication rate between the different groups. Conclusion: The use of advanced detection technologies led to a higher number of identified SNs without an increase in overall operation time, possibly indicating an improved surgical efficiency. Operation time per harvested SN decreased; the average FN rate remained 11.9% and was unchanged over 23 y. There was no significant change in postoperative complication rate.

Laser excision of a typical carcinoid tumor of the larynx: a case report.

Neuroendocrine carcinomas of the larynx include a range of rare tumors which have variable biologic behavior, affecting treatment and prognosis. Among these, typical carcinoid tumors are the least common type. Prognosis of typical carcinoid tumor is better than atypical carcinoid tumor and small cell carcinoma of the larynx. Conservation surgery is the preferred treatment modality. Transoral CO2 laser surgery can be a good alternative for appropriate cases because of the functional results and less morbidity. In this article, a 71-year-old female presented with complaints of feeling a mass during swallowing. Fiberoptic examination of the larynx revealed a mass located on the right aryepiglottic fold and biopsy revealed the tumor as a typical carcinoid tumor. We describe CO2 laser excision of a typical carcinoid tumor of the larynx in this case report.

A Review of Photodynamic Therapy for Neoplasms of the Head and Neck.

Photodynamic therapy (PDT) involves the use of a phototoxic drug which is activated by low powered laser light to destroy neoplastic cells. Multiple photosensitizers have been studied and tumors have been treated in a variety of head and neck sites over the last 30 years. PDT can effectively treat head and neck tumors, particularly those of the superficial spreading type, and the classic application of this technology has been in the patient with a wide field of dysplastic change and superficial carcinomatosis. Interstitial treatment has been used to treat more invasive cancer. Data is available from case series and institutional experiences, but very little randomized data is available. We review the mechanisms of action, historical development, available data, and current knowledge regarding PDT for the various head and neck subsites, and discuss possible future directions, with an emphasis on clinical application.

Local control in sinonasal malignant melanoma: Comparing conventional to hypofractionated radiotherapy.

BACKGROUND: The purpose of this study was to analyze the effect of fractionation schedule on local control in postoperative radiotherapy (RT) for sinonasal malignant melanoma. METHODS: Sixty-three patients who were treated with surgery and postoperative RT in 4 accredited head and neck cancer centers in the Netherlands between 1998 and 2013 were retrospectively studied. Outcomes with conventional fractionation (2-2.4 Gy per fraction; n = 27) were compared to hypofractionation (4-6 Gy per fraction; n = 36). The primary endpoint was local control and the secondary endpoint was toxicity. RESULTS: Comparable local control rates were found after 2 and 5 years (63% vs 64% and 47% vs 53%; P = .73 for, respectively, conventional fractionation vs hypofractionation). Local recurrences were predominantly present ipsilateral (92%) and within the irradiated volume (88%). Late toxicity grade ≥ 3 was observed in 2 of 63 patients, 1 patient in both groups. CONCLUSION: Radiotherapy fractionation schedule did not influence the local control rate or the incidence of late toxicity in patients treated with surgery and RT for sinonasal malignant melanoma in this retrospective analysis. Due to this retrospective nature and the limited number of patients, strong recommendations cannot be made. Expected toxicity, patient convenience, and workload may be taken into account for the choice of fractionation schedule until conclusive evidence becomes available.

Soluble CD44 is a potential marker for the early detection of head and neck cancer.

INTRODUCTION: Head and neck squamous cell carcinoma (HNSCC) is a devastating and deadly disease, largely because it is diagnosed in late stage. Cure rates, currently at 50%, could increase to >80% with early detection. In this study, we evaluate soluble CD44 (solCD44) as an early detection tool for HNSCC by determining whether it reliably distinguishes HNSCC from benign disease of the upper aerodigestive tract. METHODS: We carried out the solCD44 ELISA on oral rinses from 102 patients with HNSCC and 69 control patients with benign diseases of upper aerodigestive tract to determine the sensitivity and specificity of the test for differentiating HNSCC from benign disease. Furthermore, we did a pilot study using methylation-specific PCR primers on oral rinses from 11 HNSCC patients with low solCD44 levels and 10 benign disease controls. RESULTS: Mean salivary solCD44 levels were 24.4 +/- 32.0 ng/mL for HNSCC patients (range, 0.99-201 ng/mL) and 9.9 +/- 16.1 ng/mL (range, 0.73-124 ng/mL) for the patients with benign disease (P < 0.0001). Depending on cutoff point and HNSCC site, sensitivity ranged from 62% to 70% and specificity ranged from 75% to 88%. Nine of 11 HNSCC and 0 of 10 controls with low solCD44 levels showed hypermethylation of the CD44 promoter. CONCLUSIONS: SolCD44 is elevated in the majority of HNSCC and distinguishes cancer from benign disease with high specificity. Whereas the solCD44 test lacks sensitivity by itself, methylation status of the CD44 gene seems to complement the solCD44 test. Our pilot data indicate that, together, these markers will detect HNSCC with very high sensitivity and specificity.

Intratracheal ectopic thyroid: case report and review.

Intratracheal ectopic thyroid tissue is a rare abnormality that can cause airway obstruction. The symptoms can easily be confused with those of bronchial asthma. We describe the case of a 40-year-old man with subglottic thyroid tissue and multinodular goiter who had been misdiagnosed earlier with bronchial asthma. After the correct diagnosis was established, the lesion was excised via an external approach. We also discuss the clinical features and management of intratracheal thyroid tissue.

Contralateral regional recurrence after elective unilateral neck irradiation in oropharyngeal carcinoma: A literature-based critical review.

BACKGROUND: The head and neck region has rich regional lymphatic network, with a theoretical risk on contralateral metastasis from oropharyngeal cancer (OPC). There is a long-standing convention to irradiate the great majority of these tumors electively to both sides of the neck to reduce the risk of contralateral regional failure (cRF), but this can induce significant toxicity. We aimed to identify patient groups where elective contralateral irradiation may safely be omitted. METHODS: PubMed and EMBASE were searched for original full-text articles in English with a combination of search terms related to the end points: cRF in OPC primarily treated by radiotherapy only to the ipsilateral neck and identifying predictive factors for increased incidence of cRF. The data from the identified studies were pooled, the incidence of cRF was calculated and the correlation with different predictive factors was investigated. RESULTS: Eleven full-text articles met the inclusion criteria. In these studies, 1116 patients were treated to the ipsilateral neck alone. The mean incidence of cRF was 2.42% (range 0-5.9%, 95% CI 1.6-3.5%). The incidence of cRF correlated only with T-stage (p=0.008), and involvement of midline (p=0.001). However, the significant correlation with T-stage can be explained by the very low incidence of cRF among T1 (0.77%), and disappeared when the incidence of cRF was compared between T2, T3,and T4 (p=0.344). CONCLUSION: The incidence of cRF in patients with OPC is very low, with involvement of midline providing the most significant prognosticator. These results call for trials on unilateral elective irradiation in selected groups.

Introducing navigation during melanoma-related sentinel lymph node procedures in the head-and-neck region.

BACKGROUND: Intraoperative sentinel node (SN) identification in patients with head-and-neck malignancies can be challenging due to unexpected drainage patterns and anatomical complexity. Here, intraoperative navigation-based guidance technologies may provide outcome. In this study, gamma camera-based freehandSPECT was evaluated in combination with the hybrid tracer ICG-99mTc-nanocolloid. MATERIALS AND METHODS: Eight patients with melanoma located in the head-and-neck area were included. Indocyanine green (ICG)-99mTc-nanocolloid was injected preoperatively, whereafter lymphoscintigraphy and SPECT/CT imaging were performed in order to define the location of the SN(s). FreehandSPECT scans were generated in the operation room using a portable gamma camera. For lesion localization during surgery, freehandSPECT scans were projected in an augmented reality video-view that was used to spatially position a gamma-ray detection probe. Intraoperative fluorescence imaging was used to confirm the accuracy of the navigation-based approach and identify the exact location of the SNs. RESULTS: Preoperatively, 15 SNs were identified, of which 14 were identified using freehandSPECT. Navigation towards these nodes using the freehandSPECT approach was successful in 13 nodes. Fluorescence imaging provided optical confirmation of the navigation accuracy in all patients. In addition, fluorescence imaging allowed for the identification of (clustered) SNs that could not be identified based on navigation alone. CONCLUSIONS: The use of gamma camera-based freehandSPECT aids intraoperative lesion identification and, with that, supports the transition from pre- to intraoperative imaging via augmented reality display and directional guidance.