Sentinel lymph node detection by means of indocyanine green using the Karl Storz VITOM® fluorescence camera: a comparison between primary sentinel lymph node biopsy versus sentinel lymph node biopsy after neoadjuvant chemotherapy

PURPOSE

The usage of radioactive Technetium^99m (Tc^99m) colloid for the purpose of sentinel lymph node biopsy (SLNB) in early breast cancer is considered the gold standard in Germany. However, new tracers, such as near-infrared (NIR) imaging agents like indocyanine green (ICG) could offer an alternative in future, as they overcome drawbacks associated with radioactive Technetium^99m (Tc^99m) like limited availability, high costs and radioactivity exposure for both patients and surgeons.

METHODS

In this double-arm retrospective study, we sought to establish the usefulness of indocyanine green as an alternative or an addition to the conventional Technetium^99m (Tc^99m) in the identification of the SLN in early breast cancer.

RESULTS

Among the 161 patients who underwent primary SLNB, 34 patients had at least 1 SLN with metastasis. Among these patients with SLN metastasis, 33 had the SLN detected by ICG; while 31 had the SLN detected by Tc^99m. The conventional Technetium^99m radiotracer failed to detect 2 patients with metastasis in this Arm of the study. Among the 87 patients who underwent SLNB after NACT, 13 patients had at least 1 SLN with metastasis. Among these 13 patients with SLN metastasis, ICG and Tc^99m had detected the SLN among 12 patients, while 1 patient had been detected by ICG alone.

CONCLUSIONS

Our results show that ICG is as effective as the radioisotope for SLNB even among patients who have undergone NACT. This trial is registered with the German Clinical Trial Register, ID: DRKS00013606.

A study on the value of computer-assisted assessment for SPECT/CT-scans in sentinel lymph node diagnostics of penile cancer as well as clinical reliability and morbidity of this procedure

BACKGROUND

Because of the increasing importance of computer-assisted post processing of image data in modern medical diagnostic we studied the value of an algorithm for assessment of single photon emission computed tomography/computed tomography (SPECT/CT)-data, which has been used for the first time for lymph node staging in penile cancer with non-palpable inguinal lymph nodes. In the guidelines of the relevant international expert societies, sentinel lymph node-biopsy (SLNB) is recommended as a diagnostic method of choice. The aim of this study is to evaluate the value of the afore-mentioned algorithm and in the clinical context the reliability and the associated morbidity of this procedure.

METHODS

Between 2008 and 2015, 25 patients with invasive penile cancer and inconspicuous inguinal lymph node status underwent SLNB after application of the radiotracer Tc-99m labelled nanocolloid. We recorded in a prospective approach the reliability and the complication rate of the procedure. In addition, we evaluated the results of an algorithm for SPECT/CT-data assessment of these patients.

RESULTS

SLNB was carried out in 44 groins of 25 patients. In three patients, inguinal lymph node metastases were detected via SLNB. In one patient, bilateral lymph node recurrence of the groins occurred after negative SLNB. There was a false-negative rate of 4 % in relation to the number of patients (1/25), resp. 4.5 % in relation to the number of groins (2/44). Morbidity was 4 % in relation to the number of patients (1/25), resp. 2.3 % in relation to the number of groins (1/44). The results of computer-assisted assessment of SPECT/CT data for sentinel lymph node (SLN)-diagnostics demonstrated high sensitivity of 88.8 % and specificity of 86.7 %.

CONCLUSIONS

SLNB is a very reliable method, associated with low morbidity. Computer-assisted assessment of SPECT/CT data of the SLN-diagnostics shows high sensitivity and specificity. While it cannot replace the assessment by medical experts, it can still provide substantial supplement and assistance.

Value and efficiency of sentinel lymph node diagnostics in patients with penile carcinoma with palpable inguinal lymph nodes as a new multimodal, minimally invasive approach

PURPOSE

The international guidelines recommend sentinel lymph node biopsy (SLNB) for lymph node staging in penile cancer with non-palpable inguinal lymph nodes (LN) but it is not recommended with palpable inguinal LN. The aim of this study was to evaluate the reliability and morbidity of SLNB in combination with an ultrasound-guided resection of suspect inguinal LNs as a new multimodal, minimally invasive staging approach in these patients.

METHODS

We performed SLNB in 26 penile cancer patients with 42 palpable inguinal LNs. Prior to the combined staging procedures the patients underwent an ultrasound examination of the groins as well as planar lymphatic drainage scintigraphy and SPECT/CT scans. During the surgical procedure, the radioactive-labelled sentinel lymph nodes and, in addition, sonographically suspect LNs, were resected under ultrasound guidance. Follow-up screening was done by ultrasound examination of the groins according to the guidelines of the European Association of Urology.

RESULTS

Nineteen groins of 42 preoperatively palpable inguinal findings were histologically tumor-positive. SLNB alone showed lymphogenic metastases in 14 groins. Sonography revealed five further metastatic groins, which would not have been detected during SLNB due to a tumor-related blockage of lymphatic drainage or a so-called re-routing of the tracer. During follow-up, none of the 28 groins with tumor-negative LN status showed any LN recurrence in this combined investigation technique. The median follow-up period was 46 (24 to 92) months. Morbidity of this procedure was low at 4.76 % in relation to the number of groins resp. 7.69 % in relation to the number of patients.

CONCLUSIONS

The results show that this combined procedure is a reliable multimodal diagnostic approach for treatment of penile cancer patients with palpable inguinal LNs. It is associated with low morbidity rates. SLNB alone would lead to a significantly higher false-negative rate in these patients. The encouraging results of this work can extend the range of indications for nuclear medicine in the form of SLNB using radioactive tracers in this patient group.

10-Year experience regarding the reliability and morbidity of radio guided lymph node biopsy in penile cancer patients and the associated radiation exposure of medical staff in this procedure

Background

The guidelines of the European Association of Urologists (EAU), of the German Society of Nuclear Medicine (DGN), and the European Society for Medical Oncology (ESMO) recommend sentinel lymph node biopsy (SLNB) for lymph node staging in penile cancer with non-palpable inguinal lymph nodes as one diagnostic method. Despite this, the method is neither widely nor regularly applied in Germany – the same applies to many other countries, which may be due to insecurity in dealing with open radioactive tracers. This study aims to assess the reliability and morbidity of this method, as well as the associated radioactive burden for clinical staff.

Methods

Between 2006 and 2016, 34 patients with an invasive penile carcinoma and inconspicuous inguinal lymph node status underwent SLNB in 57 groins after application of a radiotracer (Tc-99 m nanocolloid). We collected the results prospectively. The reliability of the method was assessed by determining the false-negative rate. In addition, we evaluated complication rates and determined the radioactive burden for the clinical staff both pre- and intraoperatively.

Results

SLNB was performed in 34 patients with penile cancer with non-palpable inguinal lymph nodes in 57 groins. In two patients inguinal lymph node metastases were detected by means of SLNB. In one patient recurrent inguinal lymph node disease was found after negative SLNB in both groins. Thus, the false negative rate was 3.13 % per patient (1/32 patients) and 3.51 % per groin (2/57 groins). The morbidity rate was 2.94 % per patient (1/34 patients) and 1.75 % per groin (1/57 groins). Radiation exposure for the clinical staff during this procedure was low at a maximum of ca. four μSV per intervention.

Conclusions

SLNB is a reliable method with low morbidity that is associated with a low radiation burden for clinical staff. Due to the enhanced methodological and logistic demands, this intervention should be performed in specialized centres and in an interdisciplinary approach.

Value and Efficacy of Sentinel Lymph Node Diagnostics in Patients With Penile Carcinoma With Nonpalpable Inguinal Lymph Nodes: Five-Year Follow-up

PURPOSE

Sentinel lymph node biopsy (SLNB) has been described as a minimally invasive method for lymph node staging in patients with a penile carcinoma and nonpalpable inguinal nodes in national and international guidelines of involved professional societies. However, this method is rarely used. The aim of this study was to validate reliability and morbidity of this method and to discuss radiation exposure of persons involved.

METHODS

Twenty-eight patients with histologically negative sentinel lymph nodes in 47 groins with nonpalpable inguinal lymph nodes were included in this study (17 T1(a/b)-, 8 T2- and 3 T3-stages). We recorded prospectively all cases of lymph node recurrence and complications in patients with initially nonpalpable inguinal lymph nodes and histologically negative sentinel lymph nodes. False-negative findings and morbidity were calculated as qualitative criteria. Inguinal regions with palpable lymph nodes and/or evidence of metastases were not considered in accordance with the guidelines.

RESULTS

During a median follow-up of 68 (4-131) months, we observed one case of bilateral lymph node recurrence and one case of prolonged inguinal lymphorrhea, which could be managed conservatively. Per inguinal region, false-negative rate was 4.25%, and morbidity rate was 2.12%; seen per patient, the rates were both 3.57%.

CONCLUSIONS

Sentinel lymph node biopsy under use of radioactive tracers is a reliable method of lymph node staging in patients with penile carcinoma and nonpalpable inguinal lymph nodes. The methodical complexity is justified by high reliability and low radiation exposure for both patient and medical staff and low morbidity rates.

Regional nodal relapse in surgically staged Merkel cell carcinoma

PURPOSE

The nodal relapse pattern of surgically staged Merkel cell carcinoma (MCC) with/without elective nodal radiotherapy (RT) was studied in a single institution.

METHOD

A total of 51 patients with MCC, 33% UICC stage I, 14% II, 53% III (4 lymph node metastases of unknown primary) were eligible. All patients had surgical staging: 23 patients sentinel node biopsy (SNB), 22 patients SNB followed by lymphadenectomy (LAD) and 6 patients LAD. In all, 94% of the primary tumors (PT) were completely resected; 57% of patients received RT, 51% of known PT sites, 33% (8/24 patients) regional RT to snN0 nodes and 68% (17/27 patients) to pN+ nodes, mean reference dose 51.5 and 50 Gy, respectively. Mean follow-up was 6 years (range 2-14 years).

RESULTS

A total of 22% (11/51) patients developed regional relapses (RR); the 5-year RR rate was 27%. In snN0 sites (stage I/II), relapse occurred in 5 of 14 nonirradiated vs. none of 8 irradiated sites (p = 0.054), resulting in a 5-year RR rate of 33% versus 0% (p = 0.16). The crude RR rate was lower in stage I (12%, 2/17 patients) than for stage II (43%, 3/7 patients). In stage III (pN+), RR appeared to be less frequent in irradiated sites (18%, 3/14 patients) compared with nonirradiated sites (33%, 3/10 patients, p = 0.45) with 5-year RR rates of 23% vs. 34%, respectively.

DISCUSSION

Our data suggest that adjuvant nodal RT plays a major role even if the sentinel nodes were negative.

CONCLUSION

Adjuvant RT of the lymph nodes in patients with stage IIa tumors and RT after LAD in stage III tumors is proposed and should be evaluated prospectively.

Real-time ultrasound and freehand-SPECT. Experiences with sentinel lymph node mapping

Aim of this work is to report first experiences of the feasibility and applicability of a hybrid freehandSPECT/ultrasound (fh-SPECT/US) imaging concept, with regard to SLN imaging, in patients with breast cancer and malignant melanoma.

PATIENTS, METHODS

18 patients with breast cancer or malignant melanoma received standard SLN scintigraphy. Following this, fh-SPECT using declipse®SPECT (SurgicEye, Munich, Germany) was performed, a handheld-gamma camera-based method to visualize activity distribution within a region of interest as a cross-sectional data set. These data were transferred to an ultrasound device and sensor-navigated ultrasound was performed combining fh-SPECT data with ultrasound images, displaying superimposed images. Quality of fh-SPECT and co-registration accuracy was assigned to one of four categories and occurrence of artefacts was assessed.

RESULTS

In 4/18 examinations, there was a no deviation regarding co-registration of both data sets. For 9/18 patients, there was a deviation of <1 cm (mean 0.7±0.3 cm, range 0.3-1.0 cm). For 3/18 patients, a deviation >1 cm was present (mean 1.7±0.3 cm, range 1.5-2.0 cm). In 2/18 examinations no lymph node was found in the region of highest activity. Fh-SPECT reconstruction artifacts occurred in 6/18 examinations.

CONCLUSION

The fusion imaging concept combining SLN information with ultrasound images presented here proves to be feasible and technically successful. However, significant technical limitations were shown in fh-SPECT quality and fusion precision. Subject to technical optimisation of SPECT quality and co-registration, a meaningful contribution to the preoperative planning of lymph node therapy is imaginable. Thus, fundamentally a preoperative histological examination by fh-SPECT/US-guided biopsy is possible.

[Metastases in patients with breast cancer despite of negative sentinel lymph node. Has the concept to be changed?]

The sentinel lymph node (SLN) is of considerable prognostic relevance, because extended lymph node dissection may not be performed in patients presenting with histologically negative SLN. The aim of this study was to prove the prognostic value of the SLN-concept in these patients in long term follow-up.

PATIENTS, METHODS

The clinical follow-up of 202 women with histologically proven breast cancer and metastatically uninvolved (negative) SLN, as determined using Tc-99m-nanocolloid, was observed for a mean period of 43.4 months. Histological examination included standard methods (HE-Test) and special histochemical techniques (antibodies against cytokeratin). All patients underwent clinical examinations and mamography according a standardised schema; other procedures like ultrasound examination, routine blood tests, and chest X-ray scans were performed in patients considered doubtful after clinical examination or mamography.

RESULTS

Despite of negative SLN-findings in 14/202 patients (6.9%) metastases were found after a mean time period of 35.9 months. 4 patients showed local re-lapses, 3 patients presented with regional lymph node recurrences in the previously mapped (negative) SLN-basin, and 7 Patients developed distant metastases outside the primary lymphatic basin.

CONCLUSION

In patients negative on SLN-biopsy the axillary lymph-node-recurrence-rate was low; in 3/202 patients (1.5%) a progression in the SLN-basin could be assessed, being real concept failures. Our results underline that there is no evidence to question this concept in patients presented with clinically metastatically uninvolved early stage of breast cancer.

[Diagnostic reference value. Critical evaluation of the term with the example of nuclear medicine studies in Austria]

The aim of this study was to collect administered activities of important nuclear medicine diagnostic examinations and to identify frequencies as well as age distributions in the light of hybrid devices in Austria. Based on the survey data a re-evaluation of dose reference levels for nuclear medicine has been published in June 2010 in the novella of the Austrian Medical Radiation Protection Regulation (MedStrSchV) (8), also an estimate of the average individual doses of the total population. Accurate data on nuclear medicine studies of 34% of all Austrian nuclear medicine units could be collected.

RESULTS

Extrapolated there are about 150000 nuclear medicine examinations per year performed in Austria. The median age of patients is thereby 62 years. The results of this study resulted in 65% of the dose reference values to change, whereas 48% had to be revised downwards and 17% upwards. Additionally, 5 new reference values were included in the list; three more were taken out, however. The estimation of the individual effective patient dose for each offered examination was on average 4.7 mSv. An extrapolation based on the total exposure of the population with regard to uninvolved persons and children led to 0.07 mSv per year by nuclear medicine examinations.

CONCLUSION

The published diagnostic reference values correspond to the normal investigative practice in Austria and are compliant with most international recommendations. The term "optimal value" has been removed from the text of the law, because such wording would be misleading.

Sentinel node mapping in the prostate cancer

Aim: Sentinel node (SN) biopsy is becoming a standard procedure in the management of several malignancies. Several groups have evaluated the feasibility and value of this procedure in prostate cancer patients. In the current meta-analysis, we comprehensively and quantitatively summarized the results of these studies. Methods: Several databases including Medline, SCOPUS, Google Scholar, Ovid, Springer, and Science direct were systematically searched for the relevant studies regarding SL biopsy in the prostate cancer (“prostate” AND “sentinel” as search keywords). The outcomes of interest were sensitivity and detection rate of the procedure. Results: For detection rate and sensitivity 21 and 16 studies met the criteria of inclusion respectively. Pooled detection rate was 93.8% (95% CI 89–96.6%). Cochrane Q value was 216.077 (I2 = 89.81% and p < 0.001). Pooled sensitivity was 94% (95% CI 91–96%). Cochrane Q value was 14.12 (I2 = 0.0 and p = 0.516). Conclusion: SL biopsy can prevent unnecessary pelvic lymph node dissection in prostate cancer patients. This procedure is feasible with low false negative rate and high detection rate.