case_images: PMC11117064_01
case_images: (A) Primary tumor histology. Hematoxilyn-eosin (H&E) staining of the primary tumor. (B) Left panel: Non-brisk T cell infiltration (anti-CD3 immunohistochemistry). Right panel: Negative tumor PD-L1 expression. Magnification 20x. (C) CT scan showing the cutaneous and subcutaneous lesions (yellow circles) before the start of the therapy (Baseline) and after 4 cycles (1st evaluation). (D) CT scan of the lung metastases (red circles) before the start of the therapy (Baseline), after 3 cycles, and after 18 cycles of immunotherapy.
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case_images: PMC11117064_01_fimmu-15-1369531-g001.jpg
case_images: f1
case_images: In February 2022, after histological review at our Institute, the diagnosis of MPNST was updated to desmoplastic melanoma with Breslow thickness of 5 mm, Clark level V, mitosis 1x10Hpf, and absent ulceration ( Figure 1A ). PD-L1 expression was absent on tumor cells and TIL (Tumor infiltrating lymphocytes) were mostly excluded and localized in the peritumoral area ( Figure 1B ). CT scan performed in May 2022, after 4 cycles of combined therapy, confirmed the complete regression of the cutaneous and subcutaneous lesions, and a partial response of lung metastases ( Figures 1C, D ). CT re-evaluation scans, performed in September 2022, January 2023, and June 2023 confirmed the persistence of a complete response in the left scapular lesion, and a partial response of pulmonary lesions ( Figure 1D ).
case_images: (A) MRI of the brain after 5 cycles of therapy. Sagittal (left panel) and coronal (right panel) planes show the thickening of the pituitary gland (red circles). (B) Timeline of the creatinine plasma levels (mg/dl). Red dotted lines show start and stop of the immunotherapy, blue dotted line show start of cortisone treatment. Green box shows the normal creatinine plasma levels. (C) Histopathological features of acute interstitial nephritis. Blue arrows show interstitial lymphomonocytic infiltrate, yellow arrows show tubulitis (Periodic Acid Schiff x400).
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case_images: PMC11117064_01_fimmu-15-1369531-g002.jpg
case_images: f2
case_images: Brain MRI showed a slight thinning of the pituitary gland ( Figure 2A ). August 2023, after 20 cycles of therapy, the patient complained of slight fever and asthenia with creatinine levels of 3.67 mg/dl (0.67 - 1.17) ( Figure 2B ). At this stage, immunotherapy was suspended, and patient was referred to a nephrological consultation. Kidney biopsy evidenced an acute interstitial nephritis ( Figure 2C ). The following week, corticosteroid was switched to the oral formulation and progressively reduced (prednisone 37.5 mg/day for one month, followed by 25 mg/day for another month, followed by 12.5 mg/day) ( Figure 2B ).