Defining secure surgical bone margins in head and neck squamous cell carcinomas: The diagnostic impact of intraoperative cytological assessment of bone resection margins compared with preoperative imaging.

BACKGROUND: Imaging provides crucial staging information for treatment planning of head and neck squamous cell carcinomas (HNSCCs). Despite technical progress in imaging techniques, defining the extent of bone involvement preoperatively remains challenging and requires intraoperative information to control for adequate resection. The intraoperative cytological assessment of the bone resection margins (ICAB) provides information whether bone is infiltrated by carcinoma. The aim of this study was to assess the diagnostic value of preoperative imaging compared with ICAB in order to achieve carcinoma-free bone margins. MATERIALS AND METHODS: 108 HNSCC patients underwent preoperative computed tomography (CT), magnetic resonance imaging (MRI) and orthopantomogram (OPG) for staging and surgical planning. Curative resection was planned based on imaging. Intraoperatively, the resection margins were controlled by ICAB. The diagnostic value of preoperative imaging and ICAB was assessed with reference to the histological findings. RESULTS: CT showed a sensitivity of 89.7%, specificity of 63.0%, positive predictive value (PPV) of 85.9%, and negative predictive value (NPV) of 70.8%. MRI revealed a sensitivity of 45.5%, specificity of 66.7%, PPV of 71.4% and NPV of 40.0%. OPG-imaging had a sensitivity of 64.7%, specificity of 76.2%, PPV of 81.5%, NPV 57.1%. In comparison, ICAB provided a sensitivity of 78.6%, specificity of 95.7%, PPV 73.3%, and NPV 96.7%. The accuracy was 82.1%, 52.9%, 69.0%, and 93.5% for CT, MRI, OPG, and ICAB, respectively. CONCLUSION: Preoperative imaging lacks accuracy in defining adequate bone resection margins, compared with ICAB. ICAB supports preoperative imaging and intraoperative frozen sections to improve bone margin control.

Value of 68Ga-PSMA HBED-CC PET for the Assessment of Lymph Node Metastases in Prostate Cancer Patients with Biochemical Recurrence: Comparison with Histopathology After Salvage Lymphadenectomy.

The purpose of this study was to evaluate the accuracy of Glu-NH-CO-NH-Lys-(Ahx)-[68Ga(HBED-CC)] PET compared with morphologic imaging for the assessment of lymph node metastases (LNM) in patients with recurrent prostate cancer. METHODS: Forty-eight patients (median age, 71 y; interquartile range, 66-74 y) with biochemical recurrence (median prostate-specific antigen level, 1.31 ng/mL; interquartile range, 0.75-2.55 ng/mL) who underwent 68Ga-prostate-specific membrane antigen (PSMA) HBED-CC PET/CT or PET/MR and salvage lymphadenectomy were retrospectively included. Institutional review board approval and written informed consent were obtained from all patients for the purpose of anonymized evaluation and publication of their data. Standardized predefined lymph node (LN) template fields (n = 10) were evaluated in 68Ga-PSMA HBED-CC PET and morphologic imaging for the presence of LNM using a 5-point-scale. Additionally, SUVmean/max and size of suspicious lesions were determined. Specificity of 68Ga-PSMA HBED-CC PET imaging for PET-positive LNs was defined by comparison to histopathology. The diagnostic accuracy of 68Ga-PSMA HBED-CC PET compared with morphologic imaging alone was assessed, and areas under the receiver-operating-characteristic curves are presented. RESULTS: LNM were found histologically in 68 of 179 resected anatomic LN fields (38.0%). The specificity of 68Ga-PSMA HBED-CC PET and morphologic imaging was 97.3% and 99.1%, respectively. However, 68Ga-PSMA HBED-CC PET detected LNM in 53 of 68 histopathologically proven metastatic LN fields (77.9%) whereas morphologic imaging was positive in only 18 of 67 (26.9%). 68Ga-PSMA HBED-CC PET imaging performed significantly superior to morphologic imaging for detection of LNM (difference in the areas under the receiver-operating-characteristic curves, 0.139; 95% confidence interval, 0.063-0.214; P < 0.001). In 68Ga-PSMA HBED-CC PET, the mean size of PET-positive LN measured by CT or MRI was 8.3 ± 4.3 mm (range, 4-25 mm), and LNs, which were suspicious only in CT or MRI, presented with a mean size of 13.0 ± 4.9 mm (range, 8-25 mm). CONCLUSION: 68Ga-PSMA HBED-CC PET imaging is a promising method for early detection of LNM in patients with biochemical recurrent prostate cancer. It is more accurate than morphologic imaging and thus might represent a valuable tool for guiding salvage lymphadenectomy.

Clinical Impact of Intraoperative Cytological Assessment of Bone Resection Margins in Patients with Head and Neck Carcinoma.

BACKGROUND: Surgical treatment of head and neck squamous cell carcinoma (HNSCC) patients often results in complex defects, affecting functional structures. Frozen sections are valuable to guide resections and control for adequate margins; however, intraoperative assessment of bone remains challenging. OBJECTIVE: The objective of this study was to evaluate the clinical impact of an intraoperative cytological assessment of bone margins (ICAB) on resection status and patient outcome. METHODS: ICAB analysis (n = 267) was implemented in 102 patients during resection of HNSCC for a guided resection of affected bone. The cytological findings were compared with the final histological results of the corresponding bone margins, and the surgical consequences, R1 rates, and patient outcome of the ICAB intervention group were compared with an equal control group of 100 patients. RESULTS: ICAB revealed a sensitivity of 94.4 % [95 % confidence interval (CI) 81.3-99.3], specificity of 97.4 % (95 % CI 94.4-99.0), positive predictive value of 85.0 % (95 % CI 70.2-94.3), and negative predictive value of 99.1 % (95 % CI 96.9-99.9). Osseous R1 resections were reduced from 8 to 2.9 % (∆R1 = 5.1 %; p = 0.113), rendering a relative risk reduction (RRR) of 63.2 % with a number needed to treat (NNT) of 19.57. ICAB influenced final resection status, with a reduction of R1 resections from 17 to 7.8 % (∆R1 = 9.2 %; p = 0.026), with an RRR of 59.65 % and an NNT of 9.66. The ICAB intervention group revealed a higher disease-free survival [p(log-rank) = 0.045] and overall survival [p(log-rank) = 0.014] according to multivariable analysis. CONCLUSION: ICAB, applied as a routine diagnostic tool to supplement frozen sections, can help to reduce R1 resections in order to improve patient outcome.

Evaluation of intraoperative cytological assessment of bone resection margins in patients with oral squamous cell carcinoma.

BACKGROUND: Frozen sections are routinely applied to control for adequate resection margins. In cases in which carcinoma infiltrates bone, the intraoperative microscopic assessment of bone margins remains challenging due to technical difficulties to section native bone. The objective of the current study was to evaluate an intraoperative cytological approach to control bone resection margins in patients with bone-infiltrating oral squamous cell carcinomas. METHODS: A total of 174 cytological preparations obtained from bone margins of bone-infiltrating oral squamous cell carcinomas (28 patients) were assessed intraoperatively and compared with the corresponding histological findings. In a validation cohort (45 patients) the intraoperative cytological assessment of bone resection margins (ICAB) (104 margins) was evaluated as a diagnostic tool for routine clinical application. RESULTS: In the first patient cohort, the ICAB revealed 95.3% sensitivity and 96% specificity. The results provided an accuracy of 95.7% with a significant correlation noted between cytological and histological results (κ, 0.91; P < .001), and a positive predictive value and negative predictive value of 93.8% and 96.9%, respectively. In the validation cohort, ICAB revealed 80% sensitivity and 98.9% specificity with 98% accuracy. There was a significant correlation found between cytological and histological results (κ, 0.91; P < .001), providing a positive predictive value and negative predictive value of 80% and 98%, respectively. ICAB could predict final resection status at bone margins with 80% sensitivity and 97.5% specificity. A significant correlation was found between the cytological and histological resection status at bone margins (κ, 0,75; P < .001). CONCLUSIONS: ICAB could supplement intraoperative frozen sections of soft tissue margins as a standard procedure to control for adequate resection at bone margins.

[11C]Choline as pharmacodynamic marker for therapy response assessment in a prostate cancer xenograft model.

PURPOSE: [(11)C]Choline has been established as a PET tracer for imaging prostate cancer. The aim of this study was to determine whether [(11)C]choline can be used for monitoring the effects of therapy in a prostate cancer mouse xenograft model. METHODS: The androgen-independent human prostate cancer cell line PC-3 was implanted subcutaneously into the flanks of 13 NMRI (nu/nu) mice. All mice were injected 4-6 weeks after xenograft implantation with 37 MBq [(11)C]choline via a tail vein. Dynamic imaging was performed for 60 min with a small-animal PET/CT scanner (Siemens Medical Solutions). Six mice were subsequently injected intravenously with docetaxel twice (days 1 and 5) at a dose of 3 mg/kg body weight. Seven mice were treated with PBS as a control. [(11)C]Choline imaging was performed prior to and 1, 2 and 3 weeks after treatment. To determine choline uptake the images were analysed in terms of tumour-to-muscle (T/M) ratios. Every week the size of the implanted tumour was determined with a sliding calliper. RESULTS: The PC-3 tumours could be visualized by [(11)C]choline PET. Before treatment the T/M(mean) ratio was 1.6+/-0.5 in the control group and 1.8+/-0.4 in the docetaxel-treated group (p=0.65). There was a reduction in the mean [(11)C]choline uptake after docetaxel treatment as early as 1 week after initiation of therapy (T/M ratio 1.8+/-0.4 before treatment, 0.9+/-0.3 after 1 week, 1.1+/-0.3 after 2 weeks and 0.8+/-0.2 after 3 weeks). There were no decrease in [(11)C]choline uptake in the control group following treatment (T/M ratio 1.6+/-0.5 before treatment, 1.7+/-0.4 after 1 week, 1.8+/-0.7 after 2 weeks and 1.7+/-0.4 after 3 weeks). For analysis of the dynamic data, a generalized estimation equation model revealed a significant decrease in the T/M(dyn) ratios 1 week after docetaxel treatment, and the ratio remained at that level through week 3 (mean change -0.93+/-0.24, p<0.001, after 1 week; -0.78+/-0.21, p<0.001, after 2 weeks; -1.08+/-0.26, p<0.001, after 3 weeks). In the control group there was no significant decrease in the T/M(dyn) ratios (mean change 0.085+/-0.39, p=0.83, after 1 week; 0.31+/-0.48, p=0.52, after 2 weeks; 0.11+/-0.30, p=0.72, after 3 weeks). Metabolic changes occurred 1 week after therapy and preceded morphological changes of tumour size during therapy. CONCLUSION: Our results demonstrate that [(11)C]choline has the potential for use in the early monitoring of the therapeutic effect of docetaxel in a prostate cancer xenograft animal model. The results also indicate that PET with radioactively labelled choline derivatives might be a useful tool for monitoring responses to taxane-based chemotherapy in patients with advanced prostate cancer.

Microfluidic deletion/insertion analysis for rapid screening of KIT and PDGFRA mutations in CD117-positive gastrointestinal stromal tumors: diagnostic applications and report of a new KIT mutation.

Gastrointestinal stromal tumors (GISTs) frequently harbor mutations in the KIT and PDGFRA genes, the presence and type of which correlate with the response to the kinase inhibitor imatinib mesylate. Because most GIST mutations are deletions/insertions, we used a microfluidic apparatus to detect these size variations in polymerase chain reaction-amplified DNA. This approach, termed microfluidic deletion/insertion analysis (MIDIA), identified mutations in 30 of 50 DNA samples from paraffin-embedded CD117-positive GISTs (60%), comprising 25 deletions and five insertions. Sequencing of 14 MIDIA-positive samples confirmed the deletions/insertions, including two 3-bp alterations. Sequencing of all 20 MIDIA-negative samples also showed highly consistent results with MIDIA because 10 cases were wild type and eight displayed a single base substitution in which detection by MIDIA was not expected. Sequencing also revealed a 3-bp deletion undetected by MIDIA, thus establishing the resolution limit of MIDIA at deletions/insertions >or=3 bp. Denaturing high-pressure liquid chromatography analysis confirmed all mutations detected by MIDIA and sequencing. We pro-pose MIDIA as the first step in mutational screening of GIST because it allowed the detection of 75% of mutated cases (94% of deletions/insertions) in less than 30 minutes after polymerase chain reaction amplification and at a lower cost compared with denaturing high-pressure liquid chromatography and sequencing, which might then be used only for MIDIA-negative cases.

Immunohistochemical assessment of a testicular tumor in a 63-year-old patient: proposal for an integrated clinicopathologic approach.

A 63-year-old man was admitted to our hospital for complaints of a painless knot in his right testicle. The patient underwent orchiectomy for suspicion of malignancy. Pathologic examination detected a firm, circumscribed mass that consisted histologically of noncohesive, large, undifferentiated tumor cells diffusely infiltrating the testicular interstice. Because of the patient's advanced age and the structure of the neoplastic cells, the differential diagnosis favored a lymphoma over a malignant germ cell tumor but also included a dedifferentiated metastatic neoplasm. Immunohistochemistry was tailored accordingly and was completed using three successive panels of antibodies. Immunostaining with the first panel of antibodies directed against leukocyte epitopes (CD45, CD20, and CD3) remained negative and made a lymphoma unlikely. The subsequent panel (cytokeratin AE1/3, cytokeratin 18, and HMB-45) helped to rule out a malignant melanoma and aided to settle the diagnosis of a metastatic carcinoma. The reaction pattern of the last panel of antibodies pointed to a pulmonary origin of the putative primary tumor (PSA-negative, TTF-1-positive, and CK20-negative). The diagnosis of a metastasized poorly differentiated adenocarcinoma of the lung was confirmed by autopsy 5 months later. This case represents the extremely rare occurrence of a testicular metastasis as a primary manifestation of an occult neoplasm and shows the usefulness of an integrated site-specific clinicomorphologic approach that should precede and guide the choice of diagnostic immunoreagents.