International Journal of Surgical Pathology最新文献

Meningeal melanocytoma of the central nervous system is a rare primary melanocytic neoplasm arising from the leptomeninges' melanocytes. It chiefly occurs in the posterior cranial fossa and rarely involves the spinal cord. The literature is bereft of lumbar spinal involvement by meningeal melanocytomas. Herein, we present a 17-year-old male patient who was incidentally diagnosed with a lumbar spinal meningeal melanocytoma during an imaging workup for backache following a fall. It was an extramedullary intradural tumor and was amenable to complete surgical removal in the spinal region. This case report highlights the importance of keeping the possibility of meningeal melanocytoma as a differential diagnosis of circumscribed intradural extramedullary neoplasms.

Clear cell adenocarcinoma of the urinary tract is a rare subtype of urethral/bladder cancer that is classified as a Müllerian-type tumor and is typically associated with more aggressive behavior and worse prognosis. Individuals with underlying congenital defects involving the urinary system are known to be at an increased risk for bladder cancer in general; however, it is currently unknown whether patients with aberrant Müllerian and Wolffian duct regression and/or persistence, in addition to urinary anomalies, are at an increased risk for developing Müllerian-associated urinary tumors. In this case report, we present an extremely rare and unusual diagnosis of clear cell adenocarcinoma of the urinary tract arising in a male individual with Opitz syndrome, a congenital malformation disorder affecting multiple organ systems, including urogenital development. This presentation represents the first report of a urothelial tumor of Müllerian type occurring in a male individual with a urogenital congenital disorder.

Intraductal carcinoma (IDC) and salivary duct carcinoma (SDC) are both rare tumors of the salivary glands that most frequently occur in the parotid glands. We present an example of apocrine IDC with a frankly invasive SDC component in the parotid gland. The clinicopathologic and molecular features were analyzed in this study. A 76-year-old female patient was admitted to hospital with a parotid mass. The biopsy result showed SDC, and radical resection surgery was performed. The tumor was characterized by an intraductal proliferation forming solid and cribriform structures with abundant eosinophilic cytoplasm, accompanied by comedo necrosis and apocrine secretion, some of which showed infiltrative growth without myoepithelial cells surrounding. Identifiable intravascular tumor thrombi and extensive lymph node (12 of 30) metastases were observed. The tumor cells were positive for androgen receptor and HER2, while negative for S100 and SOX10. The final diagnosis was apocrine IDC with an invasive SDC component. Next-generation sequencing revealed MET gene fusions and other gene mutations in the tumor cells. The rare MET gene fusions have not been reported in either IDC or SDC, which may enhance our understanding of the genetic alterations in a subset of SDCs that derive from IDC.

Gouty nephropathy is an uncommon renal complication arising from chronic hyperuricemia, and its coexistence with Amyloid A (AA) (secondary) amyloidosis is exceedingly rare. We describe a 60-year-old man with a long-standing history of untreated polyarticular gout who presented with progressive joint pain, nephrotic-range proteinuria, and renal impairment. Laboratory evaluation showed elevated serum uric acid levels and impaired renal function. Renal biopsy revealed urate crystal deposits (tophi) with associated inflammatory changes consistent with gouty nephropathy, along with Congo red-positive amyloid deposits that were confirmed as AA amyloidosis by immunohistochemistry. This report highlights the critical diagnostic value of renal biopsy in identifying the rare coexistence of gouty nephropathy and AA amyloidosis within the same renal specimen. Recognizing this association is essential for prompt diagnosis and appropriate management, particularly in patients with gout who present with renal impairment and significant proteinuria.

Chronic silicone embolism represents a rare complication associated with silicone breast implants. With the increasing number of breast augmentations and reconstructive surgeries performed worldwide, awareness of implant-related pulmonary pathology is becoming increasingly important. This issue gained more public attention after the Poly Implant Prothèse scandal, which involved the use of cheaper industrial-grade silicone with a significantly higher risk of implant rupture. Here, we present a 54-year-old woman with a history of bilateral implant rupture, to highlight implant-related complications, specifically silicone migration into the lungs and other parts of the body. Ten years later, the patient experienced occasional episodes of shortness of breath for approximately 1 year, and imaging revealed multiple pulmonary lesions. Silicone particles triggered a florid chronic inflammatory reaction in the pulmonary parenchyma, rich in T-lymphocytes, histologically mimicking hematologic malignancy. Explantation of the breast implants was performed, and over the following 3 years, the patient's symptoms spontaneously subsided.

Malignancies arising from adrenal rests are extremely rare. They may occur in locations such as the retroperitoneum, testes/scrotum, ovaries, kidneys, anterior abdominal wall, spinal cord, and liver, in association with embryological development. In this article, we present a patient with ectopic adrenocortical cancer (ACC) located in the pancreas, along with a review of the relevant literature. A 57-year-old female patient was diagnosed with mixed-type breast cancer (lobular and ductal carcinoma). During further diagnostic evaluations, in addition to a malignant-appearing mass in the left breast, imaging revealed a second tumor in the left paraaortic region, located in the pancreas. This mass, measuring 6 cm, was well-circumscribed, partially necrotic, heterogeneous in appearance, and displayed no significant invasion of surrounding tissues. The patient exhibited no signs of hormonal hyperfunction, such as hypertension, electrolyte imbalances, cushingoid appearance, or hyperandrogenism. Following lumpectomy, the mass adjacent to the pancreas was surgically excised. Pathological examination revealed an oncocytic type of ACC, characterized by nuclear abnormalities, a high mitotic index, and high nuclear grade, with positivity for steroidogenic factor 1 (SF-1) (NR5A1) in immunohistochemical staining. Mitotane and glucocorticoid replacement therapy were added to the patient's treatment plan for ACC. At present, there are no signs of recurrence or metastasis. To our knowledge, this is the first reported example of ectopic ACC arising in the pancreas, diagnosed in a 57-year-old patient. ACCs should be considered in the differential diagnosis of tumors arising in nonadrenal regions.

Low-grade oncocytic tumor (LOT) is a recently described indolent renal neoplasm with over 80% of tumors harboring mutations in the TSC/MTOR signaling pathway. Typically, LOTs present as sporadic solitary tumors in patients with normal renal function, and occasionally in patients with end-stage kidney disease. However, multifocal LOTs have rarely been observed in patients with tuberous sclerosis complex (TSC). We report four patients with multifocal LOTs, including microtumors, coexisting with other renal cell neoplasms in the context of chronic kidney disease (CKD) or end stage renal disease (ESRD) in the absence of clinical features of TSC. Notably, one patient had bilateral, multifocal LOTs alongside synchronous acquired cystic disease-associated renal cell carcinoma (ACD-RCC); while two other patients had concurrent clear cell papillary renal cell tumor (CCPRCT), one with multifocal and the other with solitary LOT; the remaining patient had both coexisting CCPRCT and ACD-RCC as well as multifocal LOT. This series highlights that multifocal LOTs, including microtumors, can be seen in the setting of ESRD and can arise independently of hereditary TSC. The co-occurrence with other ESRD-associated neoplasms underscores the need for broader recognition of LOT within this clinical context.

"Ovarian thecal metaplasia" (OTM), a spindle cell proliferation in the adrenal gland, is a rare lesion that is predominantly found in postmenopausal women. Here we present 5 patients with OTM in adrenalectomy specimens resected for adrenal and nonadrenal tumors in women aged 42 to 80 years old. Extended immunohistochemical analysis was performed using contemporary markers, which revealed expression of desmin (DES), HHF35 (ACTA1), inhibin alpha (INHA), SF1, and WT1. Histologic recognition of this lesion and knowledge of its expression can aid in identification and prevent misclassification.

Benign prostatic hyperplasia (BPH) is the most common benign lesion of the prostate in aging men. However, diagnosing BPH can be challenging when it presents as an exophytic pelvic mass, particularly if radiologic continuity with the prostate and prostatic glandular components are not clearly seen. Here, we report a 57-year-old male patient with a 2-year history of obstructive voiding dysfunction. Radiologic investigations, including both computed tomography and magnetic resonance imaging, revealed a large (up to 11.9 cm) solid pelvic mass located superior to the prostate with marked mass effect. No direct continuity with the prostate or multilocular/cystic structure was identified on imaging. Pathologic evaluation of the biopsy specimen showed a hypocellular lesion consisting of bland spindle cell proliferation and small blood vessels within a loose fibrous stroma. The subsequent resection specimen showed similar histologic morphology, and prostatic glands were not identified. Immunohistochemical staining demonstrated that the tumor cells were positive for CD34, desmin, androgen receptor, and progesterone receptor. Ki67 staining indicated a very low proliferative index (<1%). The constellation of histomorphological and immunohistochemical profiles was consistent with BPH with pure stromal proliferation. To the best of our knowledge, this represents the first documented instance of BPH with pure stromal hyperplasia manifesting as a distinct pelvic mass without radiologic continuity with the prostate. This case report highlights the need for clinicians and pathologists to consider BPH in the potential diagnosis of large pelvic lesions, especially in the condition that standard prostate imaging appears normal and prostatic glands are absent.

BackgroundGastrectomy with lymphadenectomy is the standard of care for noncurative endoscopic resection (ER) (endoscopic curability C2; eCuraC2) for early gastric cancer (EGC); however, this strategy may be excessive for most patients because few patients have lymph node metastasis (LNM). In addition, whether EGCs with undifferentiated components (undiff-components) in the eCuraA group are suitable for ER remains controversial. The aim of this study was to stratify the eCuraC2 group according to LNM risk, and to verify the safety of conservative treatment for patients with undiff-components of the eCuraA group.MethodsWe retrospectively analyzed 272 patients with submucosal invasion or with undiff-components who underwent initial ER for EGC. These specimens were classified into eCura A, B, C1, and C2 groups according to the Japanese Gastric Cancer Association (JGCA) guidelines, and the rate of LNM in each group was analyzed. The key risk factors were identified by analyzing the correlation between different combinations of risk factors and LNM, and according to the LNM risk, further graded the eCuraC2 group.ResultsAmong the 162 eCuraC2 patients, 9 (5.6%) had LNM. But no patients in the other groups, including all 57 patients of the eCuraA group (T1a, < 2 cm in diameter and no ulceration) with undiff-components, had LNM. A tumor diameter >3 cm (1.7% vs 12.2%, P = .005), positive for vertical margins (1.6% vs 20.0%, P < .001), submucosal invasion (≥500 μm) (0.7% vs 6.6%, P = .012), undiff-components type dominance (0% vs 11.9%, P < .001) and lymphovascular infiltration (LVI) (1.3% vs 16.7%, P < .001) were significantly correlated with LNM. When the patients in the eCuraC2 group were divided into 4 groups based on the presence of LVI and undiff-components, the LNM rate in each group was 0/81 patients (0%) in the LVI (-) undiff-components (-) group, 3/45 patients (6.7%) in the LVI (-) undiff-components (+) group, 0/15 patients (0%) in the LVI (+) undiff-components (-) group, and 6/21 patients (28.6%) in the LVI (+) undiff-components (+) group. Finally, based on these 2 factors, eCura C2 patients were classified into 3 LNM risk grades: low (LVI (-) undiff-components (-), LNM 0%), intermediate (LVI (+) or undiff-components (+), LNM 5%), and high (LVI (+) undiff-components (+), LNM 28.6%).ConclusionBased on LVI and histological differentiation, eCuraC2 patients were classified into 3 LNM risk grades, and approximately half of the eCuraC2 patients were reclassified into the low-risk group. No LNM was found in patients in the eCuraA group with undiff-components.