Collision tumors are uncommon neoplasms composed of two histologically distinct tumor populations occurring within the same anatomic site while maintaining separate boundaries. Pancreatic collision tumors composed of solid pseudopapillary neoplasm (SPN) and well-differentiated pancreatic neuroendocrine tumor (PanNET) are rare and may be diagnostically challenging because these entities can show overlapping morphologic and immunophenotypic features and may radiographically present as a single lesion. A 41-year-old woman presented with left upper quadrant abdominal pain and was found to have a pancreatic head mass. Fine-needle aspiration favored SPN, and the patient underwent extended pancreaticoduodenectomy. Histologic examination demonstrated a 3.7 cm SPN and an adjacent 0.6 cm World Health Organization grade 1 PanNET, separated by an abrupt interface without appreciable intermingling. Immunohistochemistry showed nuclear β-catenin and cyclin D1 expression in the SPN, while the PanNET showed diffuse chromogranin and INSM1 expression with retained membranous E-cadherin. Synaptophysin was positive in both tumors, highlighting a diagnostic pitfall. Eighteen lymph nodes were negative for metastatic disease, and both tumors were confined to the pancreas. This case represents the fourth reported pancreatic SPN-WDNET collision tumor and highlights important diagnostic and classification challenges in pancreatic neoplasms that demonstrate dual differentiation. Because SPNs may exhibit partial neuroendocrine differentiation, neuroendocrine marker positivity alone should not be used to establish a diagnosis of WDNET in the setting of SPN. Instead, accurate classification requires careful integration of histomorphology and complementary immunophenotypic findings.

Splenic rupture most commonly results from blunt abdominal trauma or splenomegaly associated with infection. Diagnosing splenic injury during pregnancy is particularly challenging because its clinical signs and symptoms overlap with those of other common causes of acute abdominal pain in pregnancy. We report the case of a previously healthy 25-year-old woman (gravida 6, para 2, abortions 3, living 2) at 28 weeks and 5 days of gestation who presented with the acute onset of left upper quadrant (LUQ) abdominal pain. She had sustained mild direct abdominal trauma, followed by three weeks of progressively worsening left-sided chest pain radiating to the shoulder. Clinical evaluation and imaging revealed hemorrhagic shock and hemoperitoneum secondary to splenic injury. The patient underwent a successful exploratory laparotomy and splenectomy, during which a splenic laceration was identified. Postoperatively, she was diagnosed with infectious mononucleosis and subsequently had an uncomplicated full-term delivery. This case highlights the importance of thorough evaluation of acute abdominal pain during pregnancy and demonstrates that splenectomy can be safely performed during the third trimester when clinically indicated.

Background/Objectives: Primary splenic pregnancy (PSP) is a rare and life-threatening form of extrauterine pregnancy. Evidence is limited to case reports, and detailed analyses of all aspects of PSP are lacking. The objective is to review and summarize the clinical features, diagnostic methods, management strategies, and maternal outcomes of PSP. Methods: Review followed PRISMA 2020 guidelines. We conducted a literature search to identify all published reports of PSP in PubMed, PubMed Central, and Google Scholar published until September 2025. The search items included: 'splenic pregnancy', 'splenic ectopic pregnancy', 'ectopic pregnancy', 'pregnancy', and 'spleen'. Additional studies were identified by reviewing the reference lists of retrieved studies. We included all available full-text cases, with the inclusion criterion being PSP and the exclusion criterion being secondary splenic pregnancy. The data on clinical presentation, diagnostics, management, and outcomes were extracted and summarized descriptively. Results: Sixty published cases of PSP were collected. The average maternal age was 30.3 years, and most cases were reported in Asia. No consistent pattern of potential risk factors was observed; cases occurred between 4 and 14 weeks of gestation. Abdominal pain was the most common symptom (86.7%), often localized to the left upper quadrant. Hypotension and hemoperitoneum were present in 41.7% and 60.0% of cases, respectively. Ultrasound was the most used initial imaging modality, whereas CT and MRI showed high concordance with the final diagnosis. Most implantations occurred on the inferior and superior poles of the spleen. Surgical intervention was the predominant approach (90%), primarily involving laparotomy with splenectomy or partial splenectomy. Antibiotic use was rarely documented. Medical management was reported in selected cases, but no βhCG threshold for PSP can be inferred. Maternal survival was almost universal; the single reported death occurred in the earliest case. Conclusions: PSP should be excluded when left-sided abdominal pain, particularly with intra-abdominal bleeding, accompanies an empty uterus and elevated βhCG. No reliable βhCG threshold for treatment selection has been established, and management should be individualized based on clinical condition, diagnostic imaging, and available expertise, based on low level of evidence. Although maternal survival is excellent, spleen-preserving and non-surgical approaches remain rare.

Wandering spleen is a rare clinical entity characterized by abnormal displacement of the spleen from its normal anatomical position in the left upper quadrant. It may lead to serious complications such as torsion and infarction. Due to nonspecific clinical presentation, diagnosis can be challenging and imaging plays a crucial role. We present the case of a 20-year-old woman who presented with abdominal pain and was found to have a large pelvic mass initially suspected to be an ovarian germ cell tumor. Preoperative imaging demonstrated absence of the spleen in the left upper quadrant and a solid pelvic mass. Intraoperative findings revealed an ectopic spleen, which was confirmed histopathologically. This case highlights the importance of considering wandering spleen in the differential diagnosis of pelvic masses in young women, particularly when the spleen is not visualized in its normal location.

Situs inversus totalis (SIT) is a rare congenital laterality anomaly characterized by the complete mirror-image transposition of the thoracic and abdominal viscera. Although it is usually asymptomatic, the occurrence of acute biliary disease poses significant diagnostic and surgical challenges because the atypical location of pain and reversed anatomy may complicate clinical assessment, interpretation of imaging studies, and laparoscopic planning. We present the case of a patient with acute biliary pancreatitis associated with acute calculous cholecystitis in the setting of SIT, whose management required individualized diagnostic evaluation and surgical planning tailored to the mirror-image anatomy. A 20-year-old woman with a known diagnosis of SIT presented with a three-day history of severe epigastric pain radiating to the left upper quadrant and back, accompanied by nausea and vomiting. Laboratory evaluation demonstrated markedly elevated pancreatic enzyme levels, mild hyperbilirubinemia, and elevated liver transaminases. Abdominal ultrasonography revealed cholelithiasis and findings suggestive of SIT. Contrast-enhanced computed tomography confirmed dextrocardia, complete visceral transposition, acute pancreatitis with peripancreatic inflammatory changes, and imaging findings consistent with acute calculous cholecystitis without biliary ductal dilatation. Based on the Revised Atlanta Classification, the patient was diagnosed with mild acute biliary pancreatitis. Following clinical stabilization, laparoscopic cholecystectomy was successfully performed using a mirror-image trocar configuration adapted from the conventional technique. The postoperative course was uneventful, and histopathological examination confirmed chronic cholecystitis associated with cholelithiasis. SIT is not a contraindication to laparoscopic cholecystectomy in patients with acute biliary disease; however, it requires early recognition of the mirror-image anatomy, accurate interpretation of imaging findings, and individualized surgical planning. In this setting, mirror-image trocar placement and strict adherence to the critical view of safety are essential to minimize the risk of bile duct injury. This case demonstrates that, with meticulous preoperative anatomical assessment and an individualized surgical strategy, laparoscopic management can be performed safely and effectively.

Primary angiosarcoma of the breast is an uncommon and aggressive vascular malignancy that typically affects young women and poses diagnostic and therapeutic challenges. We report the case of a 26-year-old nulliparous woman who presented with progressive left breast swelling over approximately 18 months. Clinical examination revealed diffuse tender swelling without skin discoloration, nipple changes, or palpable lymphadenopathy. Ultrasonography demonstrated a complex cystic mass with thick septations and increased vascularity, while mammography showed global asymmetry of the left breast without suspicious calcifications. Breast MRI revealed a large 8.4 cm heterogeneously enhancing mass in the upper outer quadrant with possible focal skin involvement, but no chest wall invasion or nodal disease. Initial staging with 18F-FDG PET/CT showed no distant metastases. The patient underwent left nipple-sparing mastectomy, and histopathological examination confirmed intermediate-grade primary mammary angiosarcoma, FNCLCC grade 2. Subsequent re-excision achieved clear surgical margins. She received adjuvant ifosfamide-epirubicin chemotherapy and radiotherapy. Initial follow-up imaging showed no residual or recurrent disease. However, 14 months after completion of treatment, follow-up 18F-FDG PET/CT demonstrated new FDG-avid lytic lesions in the sacral and iliac bones, and Breast MRI revealed a small enhancing sternal lesion, consistent with delayed osseous metastatic disease. The patient was treated with palliative radiotherapy and systemic therapy. This case highlights the diagnostic complexity of primary breast angiosarcoma, its potential for delayed hematogenous osseous spread, and the value of multimodality imaging in diagnosis, staging, treatment planning, and surveillance.

BACKGROUND Histoplasma capsulatum is a thermally dimorphic fungus capable of causing progressive disseminated histoplasmosis, particularly in immunocompromised hosts. Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening hyperinflammatory syndrome resulting from uncontrolled immune activation. The coexistence of HLH and disseminated histoplasmosis is uncommon and poses significant diagnostic and therapeutic challenges. CASE REPORT A 72-year-old immunosuppressed woman with rheumatoid arthritis treated with methotrexate, hydroxychloroquine, and adalimumab presented with a 2-month history of intermittent high-grade fevers, weight loss, fatigue, and left upper quadrant pain. Physical examination revealed pallor, lethargy, and splenomegaly. Laboratory evaluation showed pancytopenia, markedly elevated ferritin, hypertriglyceridemia, and hypofibrinogenemia. Imaging demonstrated splenomegaly with splenic masses, hepatic lesions, and pulmonary nodules. Disseminated histoplasmosis was confirmed by positive urine Histoplasma antigen testing, immunodiffusion assays (H and M bands), and tissue biopsy demonstrating intracellular yeast forms consistent with Histoplasma. Bone marrow biopsy revealed hypercellularity with histiocytosis and hemophagocytosis. Elevated soluble interleukin-2 receptor levels and decreased natural killer cell activity supported secondary HLH. The patient was treated with liposomal amphotericin B followed by oral itraconazole, resulting in rapid clinical improvement and normalization of inflammatory markers, with radiographic resolution at 12 months. This case is notable for HLH associated with disseminated histoplasmosis presenting with splenic masses, an uncommon finding that can mimic malignancy or other infectious etiologies. CONCLUSIONS This case underscores the importance of considering HLH in patients with disseminated histoplasmosis presenting with persistent fever, cytopenias, and organomegaly. Early recognition and prompt antifungal therapy are critical for favorable outcomes. Although histoplasmosis can occur in immunocompetent individuals, it more commonly affects immunocompromised hosts, as in this patient, highlighting the need for vigilance in high-risk populations.

Diffuse large B-cell lymphoma (DLBCL) is the most common aggressive non-Hodgkin lymphoma and may present with nodal or extranodal disease. Thoracic and abdominal extranodal involvement can produce a radiographic appearance that closely mimics disseminated metastatic solid-organ malignancy, particularly when pulmonary masses, pleural abnormalities, splenic lesions, and bulky abdominal disease coexist. We report the case of an 81-year-old woman who initially presented with wheezing, productive cough, hypoxia, and dysuria and was referred for presumed pneumonia and urinary tract infection. Imaging subsequently revealed multiple bilateral pulmonary and pleural-based masses, bulky mediastinal and hilar lymphadenopathy, a large left upper quadrant/perisplenic mesenteric mass, splenomegaly with multiple splenic lesions, retroperitoneal and mesenteric lymphadenopathy, pleural effusion, and left hydroureteronephrosis due to malignant obstruction. Core needle biopsy of the left upper quadrant mesenteric mass demonstrated high-grade B-cell lymphoma (BCL) most compatible with diffuse large B-cell lymphoma. Immunohistochemistry showed cluster designation (CD)20, CD79a, CD10, and BCL6 positivity with negative BCL2, multiple myeloma oncogene1 (MUM1), and cyclin D1, consistent with a germinal center B-cell-like phenotype by the Hans algorithm, and Ki-67 was approximately 80%-90%. Flow cytometry identified a CD10-positive, kappa-restricted, abnormal mature B-cell population, and fluorescence in situ hybridization later demonstrated BCL2 rearrangement without MYC or BCL6 rearrangements, arguing against double-hit lymphoma. This case highlights an important diagnostic pitfall: apparent widespread metastatic disease may in fact represent aggressive lymphoma, and early tissue diagnosis is essential when the radiographic pattern does not clearly fit a single solid-organ primary.

Primary adrenal lymphoma (PAL) is an uncommon extranodal non‑Hodgkin lymphoma that typically presents with bilateral adrenal masses and carries a poor prognosis, especially when complicated by adrenal insufficiency; primary bilateral adrenal lymphoma is a rare but important cause of adrenal insufficiency and adrenal crisis, particularly when large bilateral adrenal masses are detected on imaging. A 50‑year‑old man presented with several months of constitutional symptoms, including night sweats, vomiting, weight loss, diarrhoea and myalgia, and was initially treated conservatively with symptom resolution, but four months later he was readmitted with anorexia, further weight loss, fever and left upper quadrant pain; imaging revealed bilateral adrenal masses (6.7 cm right, 4.5 cm left) with high non‑contrast attenuation (>20 Hounsfield units) and splenomegaly, and MRI confirmed progression of the right adrenal lesion to 8.5 cm. Biopsy demonstrated diffuse large B‑cell lymphoma consistent with PAL, and he was commenced on hydrocortisone and fludrocortisone replacement together with eight cycles of R‑CHOP (rituximab, cyclophosphamide, doxorubicin hydrochloride (hydroxydaunorubicin), vincristine sulfate (Oncovin), and prednisolone) and intrathecal methotrexate, achieving complete radiological remission sustained to 2016, with remission maintained until his death from sepsis and multi‑organ failure in 2023. This case illustrates the broad symptom spectrum of PAL, from B-symptoms to adrenal crisis, and underscores the importance of considering PAL in the differential diagnosis of bilateral adrenal masses with high attenuation. Early recognition of adrenal insufficiency and adrenal biopsy are critical to guide timely initiation of life-saving glucocorticoid replacement and lymphoma-directed therapy.

Hepatic artery pseudoaneurysm (HAP) with arterioportal fistula (APF) is a rare but potentially life-threatening vascular complication of hepatic trauma, most commonly described after blunt or iatrogenic injury and infrequently following penetrating trauma. Early identification and prompt endovascular management are essential to prevent severe outcomes. We report the case of a 25-year-old previously healthy male who sustained a stab wound to the right upper quadrant and epigastrium and underwent exploratory laparotomy for a grade III left hepatic lobe laceration. During postoperative recovery, he developed persistent blood-tinged drain output and epigastric pain. Contrast-enhanced CT and subsequent angiography confirmed a left hepatic artery pseudoaneurysm with an associated arterioportal fistula. Initial Gelfoam embolization failed, but definitive coil embolization via the femoral artery successfully excluded the lesion and resolved the fistulous communication. The patient experienced symptomatic improvement and was discharged in stable condition. This case underscores the importance of recognizing delayed vascular complications following penetrating liver trauma and highlights endovascular coil embolization as a safe and effective therapeutic approach. Structured postoperative follow-up remains crucial for optimal outcomes.

Background and Clinical Significance: The primary occurrence of low-grade endometrial stromal sarcoma (LG-ESS) at extrauterine sites, termed extrauterine ESS (EESS), is exceedingly rare. Case Presentation: A 49-year-old female, gravida 2 para 2 (all deliveries by cesarean section), presented with a 1-month history of epigastric and left upper quadrant abdominal pain. Abdominal computed tomography revealed a lobulated mass, measuring 4.6 cm, in the left upper quadrant with focal attachment to the splenic flexure of the colon. She underwent a laparoscopic partial gastrectomy and colectomy at a referral institution. Surgical pathology identified a 6.0 × 5.0 × 4.0 cm lobulated tumor involving the stomach with colonic invasion, diagnosed as LG-ESS (pT3N0). Immunohistochemistry showed a CD10-reactive lesion. The patient was referred to our institution for definitive gynecological surgery. After prophylactic ureteral double-J catheter insertion, she underwent laparoendoscopic single-site (LESS) total hysterectomy with bilateral salpingo-oophorectomy. The final histopathological examination of the hysterectomy specimen revealed intramural leiomyomas and benign ovarian cysts, with no evidence of ESS within the uterine corpus or adnexa. These findings confirmed a true primary EESS of nonuterine origin, consistent with AJCC stage 3 disease. The patient recovered uneventfully and was discharged during outpatient follow-up. Conclusions: This case represents one of the very few reported instances of primary LG-EESS involving the stomach and colon, simultaneously managed with a staged multidisciplinary surgical approach, including gastrointestinal resection followed by LESS hysterectomy and bilateral salpingo-oophorectomy.

A gastric volvulus occurs when the stomach rotates around itself, creating a closed-loop obstruction. This can result in a life-threatening condition in which supporting vasculature can be obstructed and lead to ischemia, necrosis, and perforation. A gastrohepatic volvulus is an exceedingly rare type of gastric volvulus in which the stomach rotates in relation to the liver, specifically around the gastrohepatic ligament. We present a case of a 39-year-old female with a history of congenital malrotation and developmental delay who presented to the emergency room for nausea and emesis. Physical examination revealed a distended and tense abdomen. A CT scan was completed, revealing abnormal positioning of a distended stomach located in the right upper quadrant and the liver located in the left upper quadrant. An emergent exploratory laparotomy revealed complete gastrohepatic volvulus. The stomach and liver were both found to have visible signs of ischemia with dusky discoloration of both organs. After manual detorsion, adequate blood flow was re-established, as evidenced by the return of normal coloration. Gastrohepatic volvulus represents an exceedingly rare and previously unreported variant of gastric volvulus. This case highlights the potential for atypical anatomical presentations to mimic other conditions, such as heterotaxy syndrome. It underscores the critical importance of maintaining a high index of suspicion in patients with acute abdominal symptoms and abnormal imaging findings. Prompt recognition, a multidisciplinary approach, and emergent surgical intervention are essential to prevent irreversible ischemic injury and associated complications.

Breast schwannomas are rare benign tumors originating from Schwann cells of peripheral nerves. They are exceedingly uncommon in the male breast and are often misdiagnosed as gynecomastia, particularly in patients on prolactin-elevating medications. We report a case of a 40-year-old male with a longstanding palpable mass in the upper outer quadrant of the left chest wall. The patient had a history of schizoaffective disorder and was on antipsychotic therapy, initially leading to the clinical presumption of gynecomastia. Diagnostic mammography revealed a well-circumscribed, noncalcified mass adjacent to the pectoralis muscle. Ultrasound demonstrated a heterogeneously hypoechoic lesion with cystic changes, classified as BI-RADS 4. Ultrasound-guided core biopsy revealed a schwannoma with S100 positivity which was confirmed on final surgical pathology after excision. This case underscores the importance of maintaining a broad differential for male breast masses and highlights the limitations of imaging alone in distinguishing rare benign neoplasms from malignancy. Biopsy remains essential for diagnosis, particularly in patients with confounding clinical risk factors.