Talimogene laherparepvec treatment to overcome loco-regional acquired resistance to immune checkpoint blockade in tumor stage IIIB-IV M1c melanoma patients.

BACKGROUND: Resistance to immune checkpoint blockade and targeted therapy in melanoma patients is currently one of the major clinical challenges. With the approval of talimogene laherparepvec (T-VEC), oncolytic viruses are now in clinical practice for locally advanced or non-resectable melanoma. Here, we describe the usage of T-VEC in stage IVM1b-M1c melanoma patients, who achieved complete remission or stable disease upon systemic treatment but suffered from a loco-regional recurrence. To our knowledge, there are no case reports so far describing T-VEC as a means to overcome acquired resistance to immune checkpoint blockade or targeted therapy. METHODS: All melanoma patients in our department treated with T-VEC in the period of 2016-2018 were evaluated retrospectively. Data on clinicopathological characteristics, treatment response, and toxicity were analyzed. RESULTS: Fourteen melanoma patients were treated with T-VEC in our center. Six patients (43%) received T-VEC first-line. In eight patients (57%), T-VEC followed a prior systemic therapy. Three patients with M1b stage and one patient with M1c stage melanoma were treated with T-VEC. These patients suffered from loco-regional progress, whilst distant metastases had regressed during prior systemic treatment. 64% of patients showed a benefit from therapy with T-VEC. The durable response rate was 36%. CONCLUSION: T-VEC represents an effective and tolerable treatment option. This is true not only for loco-regionally advanced melanoma patients, but also for patients with stable or regressive systemic metastases who develop loco-regionally acquired resistance upon treatment with immune checkpoint blockade or targeted therapy. A sensible selection of suitable patients seems to be crucial.

High-resolution ultrasound combined with power Doppler sonography can reduce the number of sentinel lymph node biopsies in cutaneous melanoma.

BACKGROUND: Sentinel lymph node biopsy (SLNB) is a widely accepted procedure to accurately stage patients with cutaneous melanoma. Disadvantages of the SLNB procedure are the overall costs and potential side effects of the operation [J Dtsch Dermatol Ges 2009;7:318-327; J Am Dermatol 2010;62:737-748]. OBJECTIVE: The purpose of our study was to evaluate whether high-resolution ultrasound combined with power Doppler sonography (PDS) is an appropriate tool for preoperative identification and characterization of sentinel lymph nodes (SLNs) in patients with cutaneous melanoma. METHODS: In a prospective study eighty-one consecutive patients with cutaneous melanoma (33 females and 48 males) in whom dissection of SLNs was indicated underwent ultrasound examinations before and after the preoperative lymphoscintigraphy. RESULTS: A total of 170 SLNs (mean 2.1 per patient) were removed and examined by histopathology. High resolution ultrasound combined with PDS correctly identified 2 of 9 positive SLNs. The sensitivity, specificity, positive predictive value, and negative predictive values of ultrasound were 22.2% (95% confidence interval (CI) = 2.8-60.0), 100% (95% CI = 97.7-100.0), 100.0% (95% CI = 15.8-100.0), and 95.8% (95% CI = 91.6-98.3), respectively. CONCLUSIONS: Although high-resolution ultrasound combined with PDS cannot substitute SLNB, this technique offers earlier diagnosis of lymph node involvement in a small subgroup of patients (with subcapsular location of metastases), and introduces the possibility to exclude those patients from SLN procedure and directly prepare them for complete lymph node dissection (CLND).

The effect of gaseous ozone treatment on egg components.

BACKGROUND: Because of the salmonella problem in poultry, disinfection technologies are necessary. Ozone is a strong oxidant used for the disinfection of surfaces, drinking water and foods. However, since ozone not only destroys bacteria but may also damage eggs, it is necessary to clarify the effects of ozone treatment on hatching egg components. In this study, doses of gaseous ozone ranging from 10 to 50 mL L(-1) were tested. The vitamin A and E contents and fatty acid composition of the egg yolk were determined. To detect possible damage to the DNA of the germ disc, single-cell gel electrophoresis was used. Moreover, free SH groups were measured in the egg white. The soluble cuticula proteins were analysed by polyacrylamide gel electrophoresis. RESULTS: The yolk was not significantly affected by ozone treatment. However, the DNA of the germ disc was attacked and a significant decrease in free SH groups in the egg white was recorded at 50 mL L(-1) ozone. Even at low ozone doses the soluble cuticula proteins were completely destroyed. CONCLUSION: Significant alterations of egg components were caused by 50 mL L(-1) ozone. At lower ozone doses the oxidative processes occurred mainly at the egg surface and are therefore probably harmless to the developing embryo.