Expression of P16INK4a in Uveal Melanoma: New Perspectives

Uveal melanoma (UM) is the most common intraocular tumor in adults. Despite sharing the name and similar morphological features with cutaneous melanoma (CM), it is an entirely different neoplasia with a particular genetic background and clinical behavior. CDKN2A is a gene located at chromosome 9p21, encoding for P16INK4a and P14(ARF) proteins, whose role as a tumor suppressor has been clearly defined in many malignant tumors. CDKN2A frequently presents germline mutations in familial CM and epigenetic downregulation in a considerable percentage of sporadic CM. It has been hypothesized that CDKN2A alterations are early events in CM development, playing a central role in the malignant transformation of melanocytes. Alterations of the CDKN2A gene reduce the expression of P16INK4a in most CM subtypes. Immunohistochemical evaluation of P16INK4a is currently used, in association with Ki67 and HMB45, in pathology practice to discriminate between dysplastic nevi and melanoma. On the other hand, CKDN2A is rarely mutated in UM, and the immunohistochemical expression of P16INK4a has only been reported in small case series. We tested P16INK4a expression on paraffin-embedded tissue sections from 9 tissue microarrays (TMAs), built with 2 mm cores derived from 133 uveal melanoma FFPE blocks, collected from 1990 to 2018, and from selected paraffin-blocks of 3 UM liver metastases. The immunohistochemical expression of P16INK4a was assessed with a visual evaluation by light microscopy and then with a digital approach. Both approaches, with an acceptable concordance rate, revealed P16INK4a expression in a large proportion of UM cases and all liver metastases, opening new possibilities of using it in the differential diagnosis between cutaneous and uveal melanoma metastases in cases of unknown primary tumor or patients with two different primary melanomas.

Optical coherence tomography angiography in quiescent choroidal neovascularization associated with choroidal nevus: 5 years follow-up

PURPOSE

To report a case of quiescent choroidal neovascularization (CNV) associated with choroidal nevus using optical coherence tomography angiography (OCTA) during 5 years follow-up.

METHODS

Observational case report.

RESULTS

A 53-year old woman was referred our department with diagnosis of choroidal nevus. At 1 year follow-up, fundus autofluorescence revealed hyper/hypoautofluorescent area, infrared image showed hyperreflective area and enhanced depth imaging OCT presented a shallow pigment epithelium detachment without exudation or hemorrhage. Fluorescein angiography and indocyanine green angiography suspected the presence of CNV. Finally, OCTA confirmed a quiescent CNV with an increased flow area of the vascular lesion without any changes in best-corrected visual acuity. At 20 months and 5 years follow-up, the CNV remained quiescent showing no clinical activity on structural SD-OCT and no changes in CNV morphology on OCTA.

CONCLUSION

This case shows the features of quiescent CNV secondary to choroidal nevus after long-term follow-up. OCTA represents a valid imaging technique that allows to identify the CNV and to monitor its progression over time.

Study of vessel density by optical coherence tomography angiography in patients with central serous chorioretinopathy after low-fluence photodynamic therapy

BACKGROUND

To perform a quantitative analysis of retinal and choriocapillaris vessel density (VD) in patients with central serous chorioretinopathy (CSC) after low-fluence verteporfin photodynamic therapy (vPDT), using Optical Coherence Tomography Angiography (OCTA).

METHODS

A total of 28 eyes of 27 patients with CSC (21 females, 6 males, mean age 47 ± 11 years) were included in this retrospective study. At baseline and after 6 months after vPDT, we evaluated VD of the superficial capillary plexus (SCP), the deep capillary plexus (DCP) and the choriocapillaris (CC) in different macular areas (whole image, parafovea and fovea). We also analyzed the central foveal thickness (CFT) and subfoveal choroidal thickness (SFCT) with Enhanced Depth Imaging-Optical Coherence Tomography (EDI-OCT).

RESULTS

Eighteen eyes and ten eyes were responders and non responders to low-fluence vPDT, respectively. The responders group showed a significant increase in VD in DCP and CC after treatment (p < 0.05). In the non responders group the VD in SCP, DCP and CC did not differ before and after treatment. We also found a significant correlation in responders group between Best-Corrected Visual Acuity (BCVA) and CFT (r = 0.566; p = 0.014) and between BCVA and the increased VD of CC (r= -0.559; p = 0.016). In non responders group, the correlation between OCT, OCTA parameters and BCVA was not statistically significant.

CONCLUSIONS

OCTA allowed us to enhance our knowledge regarding the pathophysiology of vascular changes in retinal and CC networks after low-fluence vPDT. OCTA may represent a new biomarker to evaluate the efficacy of low-fluence vPDT in the treatment of CSC.

Orbital metastases in Italy

AIM

To describe a series of Italian patients with orbital metastasis focusing on the outcomes in relation to the different primary site of malignancy.

METHODS

Retrospective chart review of 93 patients with orbital metastasis collected in a tertiary referral centre in a period of 38y and review of literature.

RESULTS

Out of 93 patients, 52 were females and 41 were males. Median age at diagnosis was 51y (range 1 to 88y). The patients have been divided into four groups on the basis of the year of diagnosis. The frequency of recorded cases had decreased significantly (P<0.05) during the last 9.5y. Primary tumor site was breast in 36 cases (39%), kidney in 10 (11%), lung in 8 (9%), skin in 6 (6%); other sites were less frequent. In 16 case (17%) the primary tumor remained unknown. The most frequent clinical findings were proptosis (73%), limited ocular motility (55%), blepharoptosis (46%) and blurred vision (43%). The diagnosis were established by history, ocular and systemic evaluation, orbital imaging studies and open biopsy or fine needle aspiration biopsy (FNAB). Treatment included surgical excision, irradiation, chemotherapy, hormone therapy, or observation. Ninety-one percent of patients died of metastasis with an overall mean survival time (OMST) after the orbital diagnosis of 13.5mo.

CONCLUSION

Breast, kidney and lung are the most frequent primary sites of cancer leading to an orbital metastasis. When the primary site is unknown, gastrointestinal tract should be carefully investigated. In the last decade a decrease in the frequency of orbital metastasis has been observed. Surgery provides a local palliation. Prognosis remains poor with a OMST of 13.5mo ranging from the 3mo in the lung cancer to 24mo in the kidney tumor.

The scattering of the fundamental torsional mode from axi-symmetric defects with varying depth profile in pipes

Guided ultrasonic waves have been successfully applied to detect defects and corrosion in plates and pipes; however, defect sizing remains challenging due to the complex profiles of the defects encountered in practice. A study of the reflection of the fundamental torsional mode T(0,1) from an axi-symmetric defect with varying depth profile has been carried out via finite element modeling and experimental validation. Defects with gradually varying depth are represented by a series of tapered steps. It is revealed that, for both tapered up- and down-steps, the wave packet is reflected only at the start and end of the steps. The reflections from the start and end of the step have been predicted, and the frequency dependence of the overall reflection from the step has been studied. The study shows that the reflection coefficient varies as a function of the ratio of the average length of the tapered defect to the wavelength due to the interference between the waves reflected from the two ends of the defect. The reflection coefficient maxima decrease as the slope of the taper becomes more gradual, this effect being more pronounced when the ratio of the average defect length to the wavelength increases.