Date: Wednesday, September 30, 2026
Presenting Institution: University of Pennsylvania

Case 1: A 76-year-old man had lifelong severe thrombocytopenia , with platelet counts typically 15-25×10?/L and a low-to-normal mean platelet volume. His mother and several maternal relatives were also affected. He presented with fatigue and exertional dyspnea. Laboratory evaluation revealed new-onset anemia and peripheral blood showed immature myeloid cells and nucleated red blood cells. The reticulocyte count was not elevated. The SPEP, vitamin B12, folate, haptoglobin, and ferritin were within normal ranges. The scanned slides show the patient's bone marrow biopsy.Case Pathology Slides

Case 2: 79-year-old female with a past medical history of rashes and itching associated with systemic eosinophilia since the 1960's, Lyme disease, lung adenocarcinoma stage IB, and dermatomyositis presents for follow-up for persistent eosinophilia. The scanned slides show the patient's bone marrow biopsy. Case Pathology Slides

Case 3: A 38-year-old male presented to the emergency department with a chief complaint of chest paint. The initial physical exam findings included non-specific lymphadenopathy of the cervical and supraclavicular lymph nodes. Initial imaging showed prominent retroperitoneal, mesenteric, and upper abdominal lymph nodes. The complete blood count at the time of presentation showed WBC 9.6, RBC 4.34, HgB 12.9, MCV 85, MCHC 35, RDW 13.1 and PLT 23. The scanned slides show the patient's bone marrow biopsy. Case Pathology Slides

Case 4: A 21-year-old female presents with a 3-year history of progressive neck pain (controlled on ibuprofen and steroids), recurrent lymphadenopathy, and intermittent constitutional symptoms, including fevers, fatigue, poor appetite, and weight loss. More recently, she has begun experiencing occipital headaches. Serology shows elevated inflammatory labs including rheumatoid factor, ESR, and CRP, as well as elevated immunoglobulins. MRI of the head shows an enhancing mass in the inferior left cerebellum measuring 4.1 cm, originating from the inferior fourth ventricle. The scanned slides show the occipital lesion biopsy. Case Pathology Slides

Date: Wednesday, July 29, 2026
Presenting Institution: Duke University

Case 1: A 52-year-old male with G6PD deficiency who presented with enlarged tonsils and an excisional biopsy was performed. Based on that diagnosis, he received three cycles of R-CHOP and radiation. Five years later, he re-presented with new bilateral neck masses noted on a routine physical. A lymph node core needle biopsy and bone marrow biopsy were performed. The scanned slides are from the original tonsil resection and bone marrow biopsy. Case Pathology Slides

Case 2: A 65-year-old man with no known history of hematolymphoid malignancy was recently diagnosed with adenocarcinoma of the proximal transverse/distal ascending colon. CT imaging performed as part of the colon cancer workup also revealed generalized lymphadenopathy and splenomegaly (15.9 cm). He subsequently underwent mesenteric lymph node excision and right colectomy. CBC showed WBC 5.9, hemoglobin 12.1, hematocrit 35.4, and platelets 158. The differential showed 51.9% neutrophils, 39.4% lymphocytes, 5.9% monocytes, and 1.9% eosinophils. The scanned slides are from the two largest mesenteric lymph nodes. Case Pathology Slides

Case 3: A 23-year-old without significant past medical history was incidentally found out to have an intracardiac mass during admission for abdominal pain. The lesion was resected and no additional chemotherapy was given. Scanned slides are from the mass lesion. Case Pathology Slides

Date: Wednesday, June 24, 2026
Presenting Institution: Cornell

Case 1: This is a 66-year-old male recently admitted for new hemolytic anemia with PET/CT showing multiple FDG avid lymph nodes above and below the diaphragm. The patient was re-admitted with acute renal failure and additional laboratory work-up concerning for hemophagocytic lymphohistiocytosis. An EBV viral load was markedly elevated. A diagnostic left axillary lymph node excisional biopsy was performed. Case Pathology Slides

Case 2: The patient is a 79-year-old female with history of hypertension, who presented with lymphadenopathy, splenomegaly, and leukocytosis. Lymph node and bone marrow biopsies were performed. CBC: WBC 56.84 k/uL, Hgb 13.2 g/dL, MCV 99.5fL, Plt 193k/uL (Differential: 62% neutrophils, 4% lymphocytes, 1% monocytes, 9% eosinophils, 1% basophils, 23% immature granulocytes). Case Pathology Slides

Case 3: The patient is a 62-year-old male who initially presented with cervical lymphadenopathy in February 2025. Imaging demonstrated extensive FDG-avid disease involving right cervical lymph nodes (levels II–V) and retroperitoneal lymph nodes. Case Pathology Slides

Date: Wednesday, May 27, 2026
Presenting Institution: Cleveland Clinic

Case 1:The patient is a 39-year-old female with a history of constipation and rectal pain. A colonoscopy identified erythematous distal rectal mucosa and rectal polyps (3 mm and 5 mm). Case Pathology Slides: H&E, CD3, CD20, CD56 | Presentation Slides

Case 2: The patient is a 71-year-old male presenting with nausea and worsening abdominal pain. Imaging showed findings concerning for a small bowel obstruction. Case Pathology Slides: H&E, CD3, CD20, CD56, CD103 | Presentation Slides

Case 3:The patient is a 58-year-old male presenting with inguinal lymphadenopathy. Case Pathology Slides: H&E, CD45, CD4 | Presentation Slides

View All Cases

Date: Wednesday, April 22, 2026
Presenting Institution: Memorial Sloan Kettering Cancer Center

Case 1: A 31-year-old male with a mediastinal mass and skin lesions. Case Pathology Slides | Presentation Slides

Case 2: A 73 year old male with right arm swelling . Case Pathology Slides | Presentation Slides

Case 3: A 73 year old woman with a history of CLL/SLL presents with new leg pain. Case Pathology Slides | Presentation Slides

Date: Wednesday, March 11, 2026
Presenting Institution: Mount Sinai

Case 1: A 5-year-old girl with no significant past medical history presented with a 3-week history of fatigue, pallor, weight loss, lower extremity pain, anemia, and thrombocytopenia. Labs showed WBC 6.5 K/uL, hemoglobin 6.8 g/dL, MCV 90.8 fL, platelet 4 K/uL. Case Pathology Slides | Presentation Slides

Case 2: An 81-year-old woman presents with progressive cervical lymphadenopathy, dysphagia, fatigue, and low-grade fevers. Imaging revealed diffuse bulky hypermetabolic lymphadenopathy above and below the diaphragm (highest SUV 57.7, largest lymph node 4.7 cm). Blood work is notable for elevated LDH of 805 U/L. An excisional biopsy was performed on a left inguinal lymph node. Case Pathology Slides | Presentation Slides

Case 3: A 69-year-old man with a history of prostate cancer status post prostatectomy and myeloid neoplasm presented with weight loss and severe hip pain for >4 weeks. Imaging revealed multiple lytic lesions in the pelvis. CBC performed at the time of the biopsy of the left iliac bone showed: WBC: 11.8 k/uL, Hemoglobin: 12.9 g/dL, Platelet: 714 k/uL, LDH: 397 U/L. Case Pathology Slides | Presentation Slides

Date: February 25, 2026
Presenting Institution: National institutes of Health (NIH)

Case 1: A 60-year-old man who experienced progressive fatigue, reduced appetite, and unintentional weight loss over the past two years. CBC performed at the time of his bone marrow evaluation showed: WBC of 3.05 K/mcL, ANC of 2.23 K/mcL, Hgb of 8.4 g/dL, HCT of 24.7%, MCV of 112.3 fL, and PLT of 38 K/mcL.
Case Pathology Slides: Bone marrow aspirate smear, H&E, CD34, CD61, myeloperoxidase, CD138 and CD56. | Presentation Slides

Case 2: A 55-year-old female presents with fevers, night sweats, and generalized bulky lymphadenopathy.
Case Pathology Slides: H&E, CD3, CD20, ICOS, EBER. | Presentation Slides

Case 3: Bone marrow biopsy and aspirate from a ~20-year-old patient with CRLF2-rearranged B-ALL post CD19/CD22 CAR T-cell therapy. Flow cytometry of the marrow aspirate was negative for residual B-ALL but revealed an abnormal population consistent with blasts expressing CD13 (dim/variable), CD33 (bright), CD38 (bright), CD45 (moderate to bright), CD64, HLA-DR, and lacking CD14. The CRLF2 rearrangement was not detected. Molecular studies showed retained JAK2 and PTPN11 mutations and identical IG? clonal sequences by ClonoSeq in both pre- and post-therapy samples.
Case Pathology Slides: Bone marrow aspirate smear, H&E, CD34, CD79a and TdT. | Presentation Slides

Case 4: 65-year-old female with an infiltrative soft tissue mass in the left submandibular region. A biopsy was performed on the left neck lymph node.
Case Pathology Slides: H&E, CD3, CD4/CD8 double stain, CD5, CD2, TIA1 and INI1. | Presentation Slides

Date: January 21, 2026
Presenting Institution: Fox Chase Cancer Center

Case 1: A 74-year-old man with CLL (dx 2017) treated with bendamustine-rituximab and ibrutinib presented with rapidly enlarging bulky mediastinal (SUV max 17) and >7 cm right axillary lymphadenopathy.
Case pathology slides: axillary lymph node core biopsy (H&E)., CD3, CD5, CD20. | Presentation Slides

Case 2: A 78-year-old man with a history of prostatic adenocarcinoma and melanoma presented with waxing and waning multi-station lymphadenopathy.
Case pathology slides: axillary lymph node excisional biopsy (H&E). CD3, CD4, CD5, CD7, CD123, Ki67. | Presentation Slides

Case 3: An 80-year-old woman with bilateral cervical lymphadenopathy and a 2.0 cm painful, pruritic, raised, ulcerated scalp lesion showed bulky head and neck disease on PET-CT (SUV max 40.7).
Case pathology slides: scalp biopsy (H&E). CD45, CD3, CD4, CD30. | Presentation Slides

Date: December 17, 2025
Presenting Institution: Emory University

Case 1: 43-year-old male with a 10-year history of waxing and waning generalized rash, refractory to multiple treatments, including topical and systemic steroids. A skin biopsy and a subsequent bone marrow biopsy was performed.
Case Pathology Slides: CD2, CD7, Bone Marrow (H&E), Skin (H&E) | Presentation Slides

Case 2: A 33-year-old male presented with sore throat, posterior oropharyngeal erythema, and cervical lymphadenopathy. Imaging revealed a large exophytic pharyngeal mass with intense FDG uptake and hypermetabolic right axillary and right upper-lobe lesions, highly concerning for metastatic squamous cell carcinoma.
Case Pathology Slides: CD20, TDT, PAX5, CD10, Tonsils (H&E), CD34. | Presentation Slides

Case 3: A 56-year-old man with stage IIIA follicular lymphoma on observation since 2005 presented with rapidly enlarging, FDG-avid bilateral cervical lymphadenopathy and tonsillar enlargement.
Case Pathology Slides: PAX5, BCL6, CD163, BCL2, Lymph node (H&E). | Presentation Slides

Date: Wednesday, November 19, 2025
Presenting Institution: Mass General Brigham

Case 1: A 38-year-old male patient presents with back pain, bilateral lower extremity neurologic symptoms, and acute urinary retention, and is found to have a thoracic tumor with cord compression, hyperleukocytosis (187.65 K/uL), anemia, and thrombocytopenia.
Case Pathology Slides: peripheral blood smear, H&E, PAX5, CD3, CD10, c-MYC. | Presentation Slides

Case 2: A 57-year-old woman with incidentally discovered infiltrative mediastinal mass (8.9 cm), lung nodules, and pleural thickening.
Case Pathology Slides: H&E, CD3-TRBC1 dual stain, CD4, CD56, Ki67. | Presentation Slides

Case 3: 82-year-old woman with 6 months of fever of unknown origin, weight loss, and fatigue and now admitted with symptomatic anemia (Hgb 6.5 g/dL) and elevated inflammatory markers (CRP 165 mg/L).
Case Pathology Slides: H&E, BM aspirate. | Presentation Slides

Case 4: 35-year-old woman with no significant past medical history presenting with a hypermetabolic skin lesion on her scalp, measuring 3.1 x 1.9 cm in size.
Case Pathology Slides: H&E, CD3, CD20, CD10, MUM1. | Presentation Slides

Date: Wednesday, October 22, 2025
Presenting Institution: NYU Grossman School of Medicine

Case 1 - A 3-year-old boy with one-week history of fever, fatigue, joint pain, refusal to move, pancytopenia and 44% blasts on CBC with demonstration of t(9;22) by FISH. Slides: 1-H&E, 2-Aspirate Smear. Case Pathology Slides | Presentation Slides

Case 2 - A 12-year-old boy with daily headaches, photophobia, ataxia, significant weight loss, peripheral blood eosinophilia, and diffuse leptomeningeal enhancement. Slides: 1-H&E, 2-CD3, 3-INI-1, 4-CD45. Case Pathology Slides | Presentation Slides

Case 3 - A 73-year-old woman with widespread lymphadenopathy, pancytopenia and B symptoms. Slides: 1-H&E, 2-CD3, 3-EBER-ISH, 4-Aspirate Smear. Case Pathology Slides | Presentation Slides

Case 4 - A 92-year-old woman with anemia and leukocytosis (62k). Slides: 1-PAX-5, 2-CyclinD-1, 3-H&E, 4-Aspirate Smear. Case Pathology Slides | Presentation Slides

Date: Wednesday, September 24, 2025
Presenting Institution: University of Pennsylvania 

Case 1: 69-year-old man who presented with abdominal pain exacerbated by eating, 30 lbs weight loss, and change in stool caliber. CT showed 9 x 9 cm small bowel mass.
Stains: H&E, CD3, CD20, PAX5, CD7
Case Pathology Slides | Presentation Slides

Case 2: 61-year-old woman with no significant past medical history presenting with isolated mildly PET avid left inguinal lymphadenopathy, 1 x 1 cm.
Stains: H&E, CD3, CD20, CD30
Case Pathology Slides | Presentation Slides

Case 3:  5-month-old male child presenting with focal seizures, fever, upper respiratory symptoms. Imaging showed 3.7 x 3.7 x 2.9 cm right frontoparietal brain mass.
Stains: H&E, CD45, CD117, P53
Case Pathology Slides | Presentation Slides

Case 4: 72-year-old man presenting with supraclavicular and submandibular lymphadenopathy, several months drenching night sweats, weight loss, and fatigue.
Stains: H&E, CD3, CD30, PAX5, CD45, Ki-67
Case Pathology Slides | Presentation Slides

Wednesday, August 27, 2025

Presenting Institution: University of Toronto

Case 1: A 49-year-old man with back pain and a lytic bone lesion in L1 vertebra.– Stains: 1- H&E, 2- CD20, 3- CD138. Case Pathology Slides | Presentation Slides

Case 2: 73-year-old man with left inguinal lymphadenopathy,– Stains: 1 – H&E, 2- CD2, 3- CD20. Case Pathology Slides | Presentation Slides

Case 3: 66-year-old man with right axillary lymph node enlargement – Stains: 1- H&E, 2- CD20, 3- CD3. Case Pathology Slides | Presentation Slides

Case 4: 44-year-old man with cervical lymphadenopathy and history of treated DLBCL,– Stains: 1- H&E, 2- Lysozyme. Case Pathology Slides | Presentation Slides

Date: Wednesday, June 25, 2025

Presenting Institution: Weill Cornell Medical College

Case 1: A 3-year-old boy presenting with stridor and found to have a 0.5 cm mass in the subglottis. Case Pathology Slides | Presentation Slides

Case 2: A 68-year-old female with a history of CLL/SLL who presents with worsening abdominal pain. PET-CT showed new FDG avid lymph nodes and multiple hepatic and splenic lesions.  Case Pathology Slides | Presentation Slides

Case 3: A 61-year-old man with a history of bipolar disorder and alcohol abuse presents with declining mental status over the past month. MRI showed multiple intracerebral lesions. Case Pathology Slides | Presentation Slides

Date: Wednesday, May 28, 2025

Presenting Institution: Cleveland Clinic

Case Pathology Slides for Cases 1 - 4

Case 1: A 74-year-old male with history of squamous cell carcinoma of the tongue now presents with new tonsillar mass. Presentation Slides

Case 2: A 65-year-old female with history of Inflammatory bowel disease on treatment presents with incidental finding of left adrenal cyst (16 cm) noted on imaging. Presentation Slides

Case 3: An 82-year-old male with history of B-cell lymphoma from an outside hospital, now presenting with visible right neck lymphadenopathy and weight loss. Abbreviated ancillary studies provided for discussion around molecular findings. Presentation Slides

Case 4: A 45-year-old male with an isolated enlarged left groin lymph node. View Slides Presentation Slides

Date: Wednesday, April 23, 2025

Presenting Institution: MSKCC

Case 1: A 66F w/ history of breast carcinoma status post adjuvant chemotherapy and radiotherapy, presenting with neutropenia (ANC 0.7 K/uL), mild anemia (Hb 10.9 g/dL, MCV 95 fL, RDW 14%), and mild thrombocytopenia (Platelets 126 K/uL). Case Pathology Slides | Presentation Slides

Case 2: A 58F w/ a history of a myeloid neoplasm favored to be oligomonocytic chronic myelomonocytic leukemia presents with widespread lymphadenopathy. Case Pathology Slides | Presentation Slides

Case 3: A 63F with a history of breast carcinoma status post cytotoxic therapy presents with widespread lytic bone lesions, marked anemia (Hb 6.9 g/dL, MCV 98fL, RDW 22.1%) and thrombocytopenia (Platelets 64 K/uL). Case Pathology Slides | Presentation Slides

Date: Wednesday, March 19, 2025

Presenting Institution: Mount Sinai

Case 1: A 70-year-old man with a history of chronic lymphocytic leukemia (CLL) with

unexplained neutrophilia. Case Pathology Slides | Presentation Slides

Case 2: A 68-year-old man with violaceous-pink raised skin lesions. Case Pathology Slides | Presentation Slides

Case 3: A 65-year-old man with a history of multiple myeloma with worsening leukocytosis. Case Pathology Slides | Presentation Slides

Case 4: A 56-year-old woman with a history of AML with inversion 16 now with pancytopenia including severe neutropenia at ~220 days post-transplant. Case Pathology Slides | Presentation Slides

Date: February 26, 2025

Presenting Institution: FCCC

Case 1: Axillary lymph node biopsy in a 63-year-old woman with a history of squamous cell carcinoma (SCC) of the anal canal. A CT scan revealed diffuse adenopathy in the chest and abdomen. Case Pathology Slides | Presentation Slides

Case 2: Inguinal lymph node biopsy in an 81-year-old woman with newly detected lymphadenopathy. Case Pathology Slides | Presentation Slides

Case 3: Level 10L lymph node biopsy in an 80-year-old man with history of CLL, undergoing resection for newly diagnosed lung adenocarcinoma. Case Pathology Slides | Presentation Slides

Case 4: Biopsy of a large soft tissue mass at the first metatarsal-phalangeal joint in a 76-year-old man. Case Pathology Slides | Presentation Slides