Case Reports in Oncology最新文献

{"title":"Orbital and Parotid Metastases from Nasopharyngeal Carcinoma: A Rare Case Presentation and Review of the Literature.","authors":"Shmokh Alsalamah, Sultan Alsumairi, Malak Almalki, Majed Pharaon, Mohammed Alessa","doi":"10.1159/000551478","DOIUrl":"10.1159/000551478","url":null,"abstract":"<p><strong>Introduction: </strong>Nasopharyngeal carcinoma (NPC) is a rare, yet aggressive malignancy characterized by various clinical presentations. Metastasis to the orbital and parotid regions presents diagnostic challenges and adds complexity to the management.</p><p><strong>Case presentation: </strong>Herein, we present a case of a 23-year-old male diagnosed with non-keratinizing undifferentiated NPC, initially presenting with orbital metastasis followed by parotid gland involvement shortly after completion of chemoradiotherapy. The patient underwent surgical intervention preceded by chemoradiotherapy, resulting in complete remission without recurrence over a 12-month follow-up period.</p><p><strong>Conclusion: </strong>This case reinforces the critical importance of vigilant long-term surveillance in high-risk NPC patients with symptom-directed and risk-adapted surveillance approaches.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"685-694"},"PeriodicalIF":0.7,"publicationDate":"2026-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13268621/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148263392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Primary Rectal Burkitt Lymphoma in a Child: A Case Report and a Review of the Literature.","authors":"Mohammad Jouby, Isel Hiba, Mohmad Debbana, Ahmad Al-Bitar, Jaber Mahmod","doi":"10.1159/000552392","DOIUrl":"10.1159/000552392","url":null,"abstract":"<p><strong>Introduction: </strong>Primary colorectal lymphomas are exceptionally rare in the pediatric population, with Burkitt lymphoma representing an even rarer subset. The nonspecific symptoms can often mimic benign conditions, leading to delays in diagnosis. We report a case of primary rectal Burkitt lymphoma in a child who presented with isolated lower gastrointestinal bleeding.</p><p><strong>Case presentation: </strong>A 10-year-old previously healthy boy presented with a 3-week history of painless, bright red blood per rectum. He had no systemic B symptoms, and his physical examination was unremarkable except for fresh blood on digital rectal examination. Initial workup revealed iron deficiency anemia and a markedly elevated serum lactate dehydrogenase. A contrast-enhanced CT scan demonstrated a large, heterogeneous mass at the rectosigmoid junction with associated mesorectal lymphadenopathy. Colonoscopy revealed multiple ulcerated polyps and a friable mass. Histopathological and immunohistochemical analyses confirmed the diagnosis of sporadic Burkitt lymphoma, characterized by a diffuse infiltrate of monomorphic lymphoid cells with a \"starry-sky\" appearance, positive for CD20 and CD10, and with a Ki-67 proliferation index approaching 100%. Staging investigations (bone marrow biopsy and lumbar puncture) confirmed localized disease (stage II). The patient was treated with a risk-adapted, multi-agent chemotherapy regimen (based on the FAB/LMB 96 protocol) followed by consolidative radiotherapy. He achieved complete remission, as confirmed by imaging 1 month posttreatment, and remains disease-free at his 18-month follow-up.</p><p><strong>Conclusion: </strong>This case highlights that primary rectal Burkitt lymphoma, though rare, should be considered in the differential diagnosis of persistent lower gastrointestinal bleeding in children. A high index of suspicion, combined with prompt endoscopic evaluation and biopsy, is crucial for early diagnosis. This report reinforces that with timely diagnosis and adherence to modern, risk-adapted chemotherapy protocols, even aggressive lymphomas in this unusual location can be highly curable, contributing to the limited body of literature on this rare entity.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"857-866"},"PeriodicalIF":0.7,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13327675/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148374594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-Term Complete Radiological Response in a Patient with Brain Metastases from HER2-Positive Breast Cancer Treated with Trastuzumab Deruxtecan: A Case Report and Literature Review.","authors":"Martina Musarra, Mariafernanda Danzè, Mariapia Marafioti, Giordana Di Mauro, Dalila Incognito, Jessica Alejandra Portillo Funes, Tindara Franchina, Mariacarmela Santarpia, Marco Donato, Giuliana Ciappina, Maria Concetta Ingemi","doi":"10.1159/000552141","DOIUrl":"10.1159/000552141","url":null,"abstract":"<p><strong>Introduction: </strong>HER2-positive (HER2+) breast cancer (BC) is associated with a high incidence of brain metastases (BMs), which negatively affect prognosis and quality of life. Local therapies, such as whole-brain radiotherapy (WBRT), stereotactic radiotherapy, stereotactic radiosurgery, and neurosurgery, allow temporary control of metastatic spread. Systemic treatments are limited by the blood-brain barrier (BBB), which restricts the passage of many therapeutic molecules. Research initially focused on small molecule tyrosine kinase inhibitors due to their low molecular weight. Recent evidence suggests that tumor-induced disruption of the BBB may increase its permeability, potentially allowing larger molecules, including antibody-drug conjugates, to cross. Although trastuzumab deruxtecan (T-DXd) has demonstrated intracranial activity, evidence of durable complete responses in heavily pretreated patients with active BMs remains limited.</p><p><strong>Case presentation: </strong>We report a case of a HER2+ BC patient with multiple (>20) active BMs, previously treated with WBRT and trastuzumab emtansine (T-DM1), who developed intracranial progression. Third-line treatment with T-DXd resulted in a complete radiological intracranial response, which has been maintained for more than 20 months under ongoing therapy, with associated improvement in neurological symptoms and quality of life.</p><p><strong>Conclusion: </strong>This case provides preliminary evidence that T-DXd may achieve deep and durable intracranial responses even in heavily pretreated patients with active BMs, including those previously treated with WBRT and T-DM1. The exceptional duration of response observed in this case appears to exceed historical expectations and warrants further investigation in this high-risk population.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"767-776"},"PeriodicalIF":0.7,"publicationDate":"2026-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13286552/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148307164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recurrence after Long-Term Use of Poly ADP-Ribose Polymerase Inhibitors Triggered by Therapy-Related Myeloid Neoplasms: A Case Report.","authors":"Yurika Yamada, Akira Yokoi, Hiroaki Kajiyama","doi":"10.1159/000552167","DOIUrl":"10.1159/000552167","url":null,"abstract":"<p><strong>Introduction: </strong>Poly ADP-ribose polymerase (PARP) inhibitors are used as maintenance therapy for recurrent ovarian cancer, but their long-term safety, especially the risk of therapy-related myeloid neoplasms, remains a concern. Here, we report a case of disease recurrence and myeloid neoplasms following long-term treatment with PARP inhibitors.</p><p><strong>Case presentation: </strong>A 49-year-old woman presented with stage IIIC (FIGO 2014), high-grade serous ovarian carcinoma. After initial surgery and chemotherapy, she achieved a complete response but experienced six recurrences between 2010 and 2017, each treated with chemotherapy. At the time of her sixth relapse, she received five cycles of nedaplatin and was subsequently administered olaparib. No notable adverse events occurred during olaparib treatment. Five years after starting olaparib treatment, she developed myelodysplastic syndrome, which progressed to acute myeloid leukemia after 2 months. Olaparib treatment was stopped following the diagnosis of myelodysplastic syndrome. She received eight cycles of venetoclax and azacitidine for approximately 1 year following her diagnosis of acute myeloid leukemia, but no hematologic response was achieved. Furthermore, she developed abnormal genital bleeding and recurrent ovarian cancer manifested as a rectovaginal fistula. Considering the seriousness of her condition, she was placed on best supportive care. She was eventually transferred to a hospice program, where she died from ovarian cancer and acute myeloid leukemia.</p><p><strong>Conclusions: </strong>While long-term PARP inhibitor therapy may prolong survival in ovarian cancer, this case highlights the risk of therapy-related myeloid neoplasms, particularly in heavily pretreated patients, and underscores the need for careful long-term monitoring and consideration of optimal maintenance duration.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"841-847"},"PeriodicalIF":0.7,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13322694/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148367097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Breast Mass as the Initial Presentation of B-Cell Acute Lymphoblastic Leukemia: A Case Report.","authors":"Amnah Zahreddin, Ammer Alabed, Ahmad Al-Bitar, Mohammad Hossein Morteza, Israa Tellawi, Aya Alsayaleh","doi":"10.1159/000552263","DOIUrl":"10.1159/000552263","url":null,"abstract":"<p><strong>Introduction: </strong>Leukemic infiltration of the breast is an exceedingly rare clinical entity, often posing a significant diagnostic challenge as it can mimic common benign or malignant breast conditions. The presence of inflammatory features may further obscure the diagnosis, delaying appropriate intervention.</p><p><strong>Case presentation: </strong>A 17-year-old female presented with a palpable right breast mass and axillary lymphadenopathy. Initial imaging revealed a 2.8 × 3.7 cm hypoechoic mass with indistinct margins and increased vascularity. Clinical findings were misinterpreted as an infectious or inflammatory process, particularly following excision of a reactive axillary lymph node. Her course was complicated by axillary vein thrombosis and a large pleural effusion. Subsequent clinical deterioration prompted a peripheral blood smear and bone marrow biopsy, which revealed B-cell acute lymphoblastic leukemia with 40% blasts, confirmed by immunohistochemistry (positive for LCA, CD20, PAX5, TdT). A breast biopsy performed after 1 month of chemotherapy revealed persistent extramedullary disease despite bone marrow remission. Treatment was escalated to hyper-CVAD, but the patient succumbed to complications, including neutropenic fever, pneumonia, and paraplegia.</p><p><strong>Conclusion: </strong>This case underscores the diagnostic consequences of leukemic breast infiltration. A high index of suspicion for hematological malignancy is essential when evaluating breast masses, particularly in young patients with atypical features, unexplained systemic symptoms, or a progressive course despite antibiotics. Fine-needle aspiration (FNA) coupled with immunophenotyping or flow cytometry is a rapid and effective diagnostic tool that can prevent unnecessary surgeries and ensure the timely initiation of systemic chemotherapy for managing this aggressive disease.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"848-856"},"PeriodicalIF":0.7,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13327674/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148374592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Congenital Acute Lymphoblastic Leukaemia with Hyperleucocytosis in a Full-Term Neonate: A Case Report.","authors":"Rasha Ebraheem, Amjad Mohammad Bashir Soudan, Ibraheem Ali Al Ali, Nader Eid","doi":"10.1159/000552168","DOIUrl":"10.1159/000552168","url":null,"abstract":"<p><strong>Introduction: </strong>Congenital leukaemia is a rare neonatal malignancy (<1% of childhood leukaemias) that often presents with nonspecific signs such as hepatosplenomegaly, skin lesions, and haematological abnormalities, making diagnosis challenging.</p><p><strong>Case presentation: </strong>We report a 25-day-old full-term female neonate with fever, multiple subcutaneous nodules, bruising, petechiae, and hepatosplenomegaly. Laboratory investigations demonstrated extreme hyperleukocytosis, severe anaemia, thrombocytopenia, elevated lactate dehydrogenase, and hyperuricaemia. Peripheral blood smear revealed numerous lymphoblasts. Flow cytometry confirmed B-cell precursor acute lymphoblastic leukaemia. The patient received supportive care and was subsequently referred for chemotherapy. However, she died shortly after transfer.</p><p><strong>Conclusion: </strong>Congenital leukaemia should be considered in neonates with unexplained hepatosplenomegaly, skin lesions, pallor, and marked leucocytosis. Early peripheral blood smear evaluation and immunophenotyping are essential.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"867-873"},"PeriodicalIF":0.7,"publicationDate":"2026-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13331472/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148390079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Malignant Mesothelioma Extending from Peritoneum to Pleura: A Diagnostic Challenge and Case Report.","authors":"Thanh Thuy Phan, Thi Quynh Huong Pham, Van Duy Le, Thi Lan Tran, Van Chuong Tran, Nguyen Thị Hoa Mai, Thu Phuong Phan, Van Giap Vu","doi":"10.1159/000551912","DOIUrl":"10.1159/000551912","url":null,"abstract":"<p><strong>Introduction: </strong>Sarcomatoid malignant peritoneal mesothelioma (SM-MPM) is an exceptionally rare and aggressive subtype of peritoneal mesothelioma, often presenting with nonspecific symptoms such as ascites. Due to its subtle clinical manifestations, diagnosis is frequently delayed, resulting in poor prognosis. Early and accurate identification is crucial for guiding appropriate therapeutic strategies.</p><p><strong>Case presentation: </strong>We report the case of a 52-year-old woman with no history of smoking, alcohol use, or asbestos exposure, who previously underwent subtotal hysterectomy for uterine fibroids in 2017. Ten months prior to admission, she developed progressive abdominal distension, fatigue, and ascites, accompanied by elevated CA-125 levels. Initial symptomatic improvement was achieved with diuretics, but no definitive diagnosis was established. Eight months later, she was readmitted with recurrent ascites, chest tightness, and dyspnea. Imaging revealed right pleural effusion, pneumothorax, and peritoneal thickening. Pleuroscopic biopsy showed reactive mesothelial proliferation. One month into hospitalization, rapid re-accumulation of ascitic fluid prompted repeat imaging, which demonstrated irregular peritoneal thickening and nodularity. Laparoscopic peritoneal biopsy with immunohistochemistry confirmed the diagnosis of SM-MPM. The disease was staged as T3N0M1 based on the Peritoneal Cancer Index (PCI), indicating advanced disease with poor prognosis. The patient was referred to a specialized oncology center for further management.</p><p><strong>Conclusions: </strong>This case underscores the diagnostic challenges of SM-MPM, particularly in patients presenting with recurrent unexplained ascites and multiple serous effusions. It highlights the importance of maintaining a high index of suspicion and the pivotal role of laparoscopy, immunohistochemistry, and multidisciplinary collaboration in achieving timely diagnosis and optimizing patient outcomes.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"785-795"},"PeriodicalIF":0.7,"publicationDate":"2026-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13286493/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148307232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gastric Metastasis with Lobular Phenotype from a Primary Invasive Ductal Breast Carcinoma: A Case Report.","authors":"Nisreen Khazeam, Leen Ibrahim Khouri, Modar Omar Alajlani, Ahmad Al-Bitar","doi":"10.1159/000552180","DOIUrl":"10.1159/000552180","url":null,"abstract":"<p><strong>Introduction: </strong>Breast cancer is a leading cause of cancer-related mortality in women, with common metastatic sites including bone, lung, liver, and brain. Metastasis to the gastrointestinal tract, particularly the stomach, is a rare occurrence, with a reported clinical incidence of 0.2-0.7%. Its nonspecific symptomatology and heterogeneous endoscopic presentation often lead to diagnostic confusion with primary gastric cancer or benign conditions.</p><p><strong>Case presentation: </strong>We report the case of a 51-year-old woman with a history of stage IIIC invasive ductal breast cancer, treated 9 years prior with multimodal therapy. She presented with a 6-month history of severe abdominal pain, significant weight loss (15 kg), vomiting, and diarrhea, initially managed as a <i>Helicobacter pylori</i>-associated gastric ulcer without improvement. Upper endoscopy revealed a large, raised-margined ulcer. Biopsy and immunohistochemical analysis were pivotal, showing a profile positive for CK7, GATA3, and estrogen receptors and negative for E-cadherin, confirming metastatic breast carcinoma. Staging CT scans showed no other metastatic disease. The patient was initiated on systemic hormonal therapy with an aromatase inhibitor combined with a CDK4/6 inhibitor.</p><p><strong>Conclusion: </strong>This case underscores that gastric metastasis should be considered in breast cancer survivors presenting with persistent upper GI symptoms, even many years after initial remission. It highlights the critical role of immunohistochemistry in achieving a correct diagnosis, which is essential for guiding appropriate systemic therapy and avoiding unnecessary surgical intervention. A multidisciplinary approach is paramount for managing this rare manifestation of advanced breast cancer.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"815-822"},"PeriodicalIF":0.7,"publicationDate":"2026-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13299161/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148343949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metastatic Involvement of the Ureter from Recurrent Pancreatic Cancer in a Patient with Multiple prior Malignancies: A Case Report.","authors":"Hiroshi Shintani, Sohei Iwagami, Katsuji Tokuhara, Naoki Kataoka","doi":"10.1159/000552132","DOIUrl":"10.1159/000552132","url":null,"abstract":"<p><strong>Introduction: </strong>Ureteral metastasis is an exceptionally rare manifestation of malignant disease, with pancreatic cancer as the primary source being particularly uncommon. Because ureteral involvement typically reflects advanced systemic disease and is associated with poor prognosis, early and accurate diagnosis is essential for appropriate clinical management.</p><p><strong>Case presentation: </strong>A 74-year-old man with a history of surgically treated gastric, colorectal, and pancreatic cancers was under routine follow-up after curative resection of pancreatic cancer. Surveillance computed tomography revealed a periureteral mass accompanied by left-sided hydronephrosis. Subsequently, serum tumor marker levels increased, and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography demonstrated increased metabolic uptake confined to the periureteral lesion. As imaging findings alone were insufficient to determine the primary origin, surgical resection was performed. Histopathological and immunohistochemical analyses revealed features consistent with pancreaticobiliary adenocarcinoma, confirming periureteral metastasis from recurrent pancreatic cancer. Postoperatively, systemic chemotherapy with gemcitabine plus nab-paclitaxel was initiated.</p><p><strong>Conclusion: </strong>This case highlights that pancreatic cancer can cause isolated ureteral metastasis even several years after curative surgery. In patients with a history of multiple malignancies, newly identified periureteral lesions should raise suspicion for metastatic disease, and histopathological confirmation is essential to establish the primary origin and guide optimal systemic therapy.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"833-840"},"PeriodicalIF":0.7,"publicationDate":"2026-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13309097/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148343952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Rare Trio: Concomitant Bone Marrow Involvement by Smoldering Myeloma and Systemic Mastocytosis with an Associated Hematologic Neoplasm and ALECT-2 Renal Amyloidosis - A Case Report and Literature Review.","authors":"Dina Soliman, Fadel Alqatati, Deena Mudawi, Abdulrahman F Al-Mashdali, Imran Nazir, Firyal Ibrahim, Shehab Fareed","doi":"10.1159/000552043","DOIUrl":"10.1159/000552043","url":null,"abstract":"<p><strong>Introduction: </strong>Systemic mastocytosis (SM) is a clonal disorder characterized by abnormal accumulation of mast cells in various tissues and is categorized into distinct subtypes per the World Health Organization (WHO) 2022 classification. When SM is associated with another hematologic neoplasm, typically of myeloid lineage, it is classified as systemic mastocytosis with an associated hematologic neoplasm (SM-AHN). Coexistence with plasma cell dyscrasias is rare, with fewer than 15 published cases involving either smoldering multiple myeloma (SMM) or multiple myeloma (MM). ALECT-2 amyloidosis, a non-immunoglobulin-derived amyloid subtype, is typically isolated to the kidneys and has not been previously reported in context of SM-AHN.</p><p><strong>Case presentation: </strong>We describe the first documented case of concurrent SMM, SM-AHN, and ALECT-2 amyloidosis in a 67-year-old male of Egyptian descent with stage 3B chronic kidney disease and proteinuria. Diagnostic workup revealed lambda-restricted plasma cell infiltration, KIT D816V-positive multifocal mast cell aggregates, and renal-limited ALECT-2 deposits confirmed by mass spectrometry. Serum immunofixation electrophoresis showed a monoclonal lambda free light-chain band without a corresponding intact heavy-chain M-protein, and serum protein electrophoresis showed no M-spike. The patient was managed with active surveillance, and the available records document approximately 24 months of follow-up.</p><p><strong>Conclusion: </strong>This case highlights the diagnostic and clinical implications of overlapping hematologic and renal disorders, underscores the role of proteomic amyloid typing in avoiding misdiagnosis, and explores potential pathogenic interplay between mast cells, plasma cells, and the marrow microenvironment. This case also underscores the importance for clinicians remaining vigilant and considers the possibility of non-AL amyloidosis, even when a plasma cell disorder diagnosis has been documented.</p>","PeriodicalId":9625,"journal":{"name":"Case Reports in Oncology","volume":"19 1","pages":"823-832"},"PeriodicalIF":0.7,"publicationDate":"2026-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13309096/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148343937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}