Case Report: Successful Immunotherapy Improved the Prognosis of the Unfavorable Subset of Cancer of Unknown Primary

Abstract

BackgroundCancer of unknown primary (CUP) is heterogeneous and has a wide variety of clinical presentations and a poor prognosis in most patients, with a median overall survival of only 6 months. The development of molecular profiling contributes to precision therapy, and targeted drugs and immune checkpoint inhibitors (ICIs) greatly promote individualized treatment.Case presentationHere, we reported a case of an unfavorable subset of CUP who had a long time of survival after the immunotherapy-prominent comprehensive treatment. A 48-year-old man presented with back pain and a cough. A diagnostic work-up showed bone marrow, multiple bones, and lymph node metastasis. Lymph node pathology implies metastatic poorly differentiated cancer. Next-generation sequencing (NGS) showed no special targets, but the tumor proportion score (TPS) of programmed death-ligand 1 (PD-L1) was 80% and the tumor mutation burden (TMB) was 16.7 per million bases. After two cycles of pembrolizumab 200 mg D1 plus nanoparticle albumin-bound (nab)-paclitaxel 200 mg D1&8 (q3w), PET-CT and bone marrow aspiration cytology showed a complete response (CR). Subsequently, pembrolizumab alone was used for three months. The left inguinal lymph nodes showed new metastasis. After two cycles of the combination treatment of pembrolizumab and (nab)-paclitaxel, a partial response (PR) was achieved. After seven months, retroperitoneal lymph nodes showed new metastasis, and the sequential treatment with radiotherapy and pembrolizumab exhibited encouraging efficacy. To date, the patient has survived nearly 40 months with the combination therapy.ConclusionsThe ICI-prominent comprehensive treatment provided clinical benefit for the reported case of CUP. Thus, CUP patients with markers of benefiting from immunotherapy should be actively treated with immunotherapy to improve their prognosis.

Case Report: Combined pembrolizumab, 5-fluorouracil, and cisplatin therapy were remarkably effective in p16-positive squamous cell carcinoma of unknown primary

“…One-third of the cases in the NivoCUP-2 trial had a PD-L1 TPS ≥ 1% ( 38 ). A recent case report also showed that when the TMB was high, the combination of pembrolizumab and chemotherapy was effective, even in patients in ‘unfavorable prognosis’ CUP groups ( 47 ). It has been reported that viral antigens in anti-PD-1 treatment results are one of the predictive factors ( 48 , 49 ).…”

PD-L1 and PU.1 expression in malignant peripheral nerve sheath tumors

“…Однако в исследовании L. Davis et al у пациентов с новообразованиями, развившимися на фоне НФ 1-го и 2-го типа, не было обнаружено связи между экспрессией PD-L1, инфильтрацией CD8+ лимфоцитами и выживаемостью больных [9]. В настоящее время из литературы известно о четырех пациентах с ЗООПН с различными уровнями экспрессии PD-L1, у которых наблюдали полный метаболический ответ на анти-PD-1 терапию [9][10][11]. Помимо злокачественных опухолей в некоторых исследованиях приводятся данные об увеличении экспрессии PD-L1 development and prognosis of MPNSTs has not yet been determined.…”