UNASSIGNED: This work aims to report the challenging diagnosis, treatment, and follow-up of a patient with persistent fetal vasculature (PFV) and retinoblastoma (RB).
UNASSIGNED: A 22-month-old boy presented with unilateral RB stage VB in the right eye and PFV in both eyes. The patient was treated with transpupillary laser ablation and systemic chemotherapy.
UNASSIGNED: Treatment resulted in complete tumor regression. Two years after the last systemic chemotherapy treatment, magnetic resonance imaging (MRI) showed increased signal intensity with progressive optic nerve enhancement, where intraneural malignancy could not be excluded. Enucleation of the right eye was performed. Histopathologic review showed no residual active malignancy in the enucleated globe.
UNASSIGNED: This case demonstrates the importance of a thorough clinical examination to establish the correct diagnosis and to rule out RB before any surgery. This case also highlights the importance of regular follow-ups after tumor regression with full a ophthalmologic examination, B-scan, and periodic MRI.

Upper tract urothelial carcinoma (UTUC) is a relatively rare disease that accounts for 5% to 10% of all urothelial carcinomas (UCs). Radical nephroureterectomy (RNU) with a bladder cuff is the current gold standard for the management of UTUC; however, endoscopic ablation is also an option for low-risk UTUC to preserve kidney function. Herein, we present two cases of solitary kidney with a right lower ureteral tumor. Both patients underwent left RNU in the past. An 82-year-old man with a right ureteral tumor whose histopathological examination revealed low-grade UC. Laser ablation was performed with ureteroscopy, and there was no recurrence for 7 years after treatment. A 67-year-old woman with a right lower ureteral tumor whose histopathological examination also revealed low-grade UC. Laser ablation was performed, and there was no recurrence for 5 years after the treatment. We closely followed-up our two patients after RNU. This allowed for early detection of tumor recurrence, after which we could perform laser ablation therapy.

Laser interstitial thermotherapy (LITT) is a relatively new focal therapy technique for the ablation of localized prostate cancer. In this study, for the first time, we are integrating ex vivo pathology and magnetic resonance imaging (MRI) to assess the imaging characteristics of prostate cancer and treatment changes following LITT. Via a unique clinical trial, which gave us the availability of ex vivo histology and pre- and post-LITT MRIs, (1) we investigated the imaging characteristics of treatment effects and residual disease, and (2) evaluated treatment-induced feature changes in the ablated area relative to the residual disease. First, a pathologist annotated the ablated area and the residual disease on the ex vivo histology. Subsequently, we transferred the annotations to the post-LITT MRI using a semi-automatic elastic registration. The pre- and post-LITT MRIs were registered and features were extracted. A scoring metric based on the change in median pre- and post-LITT feature values was introduced, which allowed us to identify the most treatment responsive features. Our results show that (1) image characteristics for treatment effects and residual disease are different, and (2) the change of feature values between pre- and post-LITT MRIs can be a quantitative biomarker for treatment response. Finally, using feature change improved discrimination between the residual disease and treatment effects.