Case Reports in Pathology最新文献

Collision tumors are rare tumors comprising two morphologically distinct tumors within the same organ without histological admixture. Thyroid collision tumors are extremely rare. We present a case of a 64-year-old male patient with a radiologically suspicious, TI-RADS-TR4 lesion in the right lobe of the thyroid. Fine needle aspiration cytology (FNAC) from the lesion was diagnosed as medullary thyroid carcinoma. Total thyroidectomy with central and right lateral neck dissection was performed. On histopathological evaluation, a collision tumor was identified. Components of the collision tumor were multifocal medullary thyroid carcinoma (MTC) and multifocal infiltrative follicular variant of papillary thyroid carcinoma (PTC). Several hypotheses have been suggested regarding the pathogenesis of the collision tumor. Further management and prognosis of the tumor depend on the component with the higher stage and more aggressive behavior. The case report emphasizes the need for thorough sampling of uninvolved areas in the specimen for microscopic evaluation and staging of each component.

Introduction: Placental site nodules (PSNs) are uncommon lesions typically found in uterine specimens and extremely rarely in extrauterine locations such as the fallopian tubes. PSNs are usually discovered incidentally and result from prior implantation sites. This case report describes an unexpected PSN found in a fallopian tube during a cesarean section with concurrent tubal sterilization. Case Presentation: A 38-year-old multiparous woman (gravida 4, para 2) with a previous vaginal delivery underwent tubal sterilization during a cesarean section. The surgical procedure was uneventful, with no macroscopic abnormalities noted. The patient's medical history included treatment for an ectopic pregnancy with methotrexate. Pathological examination revealed the right fallopian tube to be unremarkable. However, the left fallopian tube contained a 0.3 cm nodule within its wall, characterized by central hyalinization, dystrophic calcifications, and peripheral intermediate trophoblast cells. Immunohistochemical analysis demonstrated GATA3 positivity and a low proliferative index (MIB-1). The absence of mitotic activity, necrosis, and typical morphology confirmed the diagnosis of a PSN. Discussion: PSNs are benign lesions derived from intermediate extravillous trophoblasts. Their identification relies on both morphological characteristics and immunohistochemical staining. The differential diagnosis includes various trophoblastic diseases, which can be distinguished from PSNs by their specific features. This case contributes to the limited literature on extrauterine PSNs, highlighting the importance of recognizing these lesions in atypical locations and differentiating them from pathologies that are more aggressive. Conclusion: This case highlights the rarity of PSNs in the fallopian tubes and underscores the importance of comprehensive pathological analysis for an accurate diagnosis.

Synovial sarcomas are rare malignant soft tissue tumors with significant metastatic potential. Although they can occur in various parts of the body, they are most commonly found on the extremities. These tumors typically develop in children and young adults, making occurrences in individuals over 50 years of age unusual. Due to their slow-growing and nonpainful nature, synovial sarcomas can often be mistaken for benign pathologies. The standard treatment involves complete surgical excision with negative margins, which offers a favorable 5-year prognosis. This case highlights the importance of early recognition and intervention in managing soft tissue sarcomas. In this case report, we present a 57-year-old African male with a 2-year history of gradual, nonpainful swelling on his left hand, diagnosed as synovial sarcoma. The patient was successfully treated with complete surgical excision.

Encapsulated papillary carcinoma (EPC) is an invasive carcinoma which shows papillary architecture within a thickened fibrous capsule. Multiple studies have shown that this tumor follows an indolent course with excellent prognosis, and as such, it is recommended that it be staged as in situ lesions. It is an uncommonly encountered tumor most often diagnosed in postmenopausal females. As breast cancer in males is overall rare, available data on diagnosis, management, and outcomes of EPC in males is limited. Typically, cases of EPC that present with advanced stage and/or lymph node metastases show an associated invasive process. We present a case of pure EPC in a male patient with associated skin ulceration and positive lymph nodes, leading to a final stage of ypT4bN1a. The present report underscores the indolent nature of EPC, even when diagnosed at an advanced stage.

Salivary gland carcinosarcoma is a combination of malignant epithelial and sarcomatous tumors and can develop from a preexisting pleomorphic adenoma or de novo. These tumors are rapidly growing infiltrative tumors and have an extremely poor prognosis, with a high frequency of lymphatic and hematogenous spread at the time of diagnosis. Approximately half of the cases of carcinosarcoma arise from preexisting pleomorphic adenoma with a long-standing clinical history of parotid mass. The carcinomatous component is most commonly squamous cell carcinoma or adenocarcinoma, while chondrosarcoma is the most frequent sarcomatous component. Our case is particularly unusual due to the presence of osteosarcomatous differentiation as the sarcomatous component. In addition to its histological rarity, our patient has never been reported a prior parotid mass or history of pleomorphic adenoma in this location. However, thorough examination of the radical parotidectomy specimen revealed sclerosed foci of pleomorphic adenoma in addition to carcinosarcoma with osteoid formation. In conclusion, we report an unusual case of carcinosarcoma ex-pleomorphic adenoma with osteoid formation and osteoclast giant cells in a patient without a history of pleomorphic adenoma or parotid mass.

Lymphoepithelioma-like urothelial carcinoma (LELUC) and plasmacytoid urothelial carcinoma (PUC) are rare subtypes. We report a case of simultaneous urothelial carcinoma composed of LELUC and PUC subtypes, along with prostatic adenocarcinoma, with successful clinical management by immunotherapy. The patient, a 54-year-old man with a 40 pack-year smoking history, presented with gross hematuria and dysuria. Imaging revealed focal bladder wall thickening. The patient underwent transurethral resection of bladder tumor (TURBT), followed by cystoprostatectomy. The TURBT revealed LELUC, with muscle invasion. The subsequent cystoprostatectomy specimen displayed a 6.0 cm ulcerative mass, which had focal penetration through the urinary bladder wall. Microscopically, the tumor consisted of sheets of enlarged and pleomorphic tumor cells, mixed with a lymphoplasmacytic infiltrate. Focal plasmacytoid and occasional signet ring cell-like morphologies were observed. Rare tumor cells showed positivity for GATA-3 and p63 immunostains, while the plasmacytoid tumor cells exhibited loss of E-cadherin expression. Additionally, adenocarcinoma of the prostate was present, with a Gleason score of 3 + 3, involving 2% of the prostate tissue. The diagnoses of LELUC, comprising 95% of the tumor, PUC, comprising 5%, and prostatic adenocarcinoma were made. Molecular studies revealed a high tumor mutational burden, and the tumor exhibited PD-L1 expression. The patient received adjuvant immunotherapy with Pembrolizumab and showed no evidence of disease for 3 years up to the time of this report. Morphologic recognition of the various subtypes of urothelial carcinoma, supported by immunohistochemistry, is essential for the proper clinical management of patients. A search of the literature on PubMed revealed no similar cases.

Intraneural vascular anomalies are rarely encountered specimens as these are not commonly resected. To the best of our knowledge, this is the first report of the histologic findings in an arteriovenous malformation (AVM) within a digital nerve. We report a rare case of an 18-year-old man with a painful mass in the left hand and middle finger who was referred to our hospital for a treatment strategy consultation. According to Schobinger's clinical classification, the patient was diagnosed with Early-Stage 3 AVMs of the left hand and was followed up for approximately 1 year. Due to increasing pain and dark purple discoloration of the finger, the AVM on the left middle finger was removed en bloc, including the skin, subcutaneous fat, and digital nerve, leaving the tendon and the periosteum. Histology revealed the abnormal vasculature of the AVM within the digital nerve and adjacent subcutaneous fibroadipose tissue. Histologically, two patterns of nerve involvement were recognized: arterioles that pushed into the nerve fascicle in a non-destructive manner, compressing the perineurium, and numerous microvessels in the endoneurium surrounded by microvascular proliferation found on the outside of the perineurium. The presence of intraneural abnormal vessels suggested that one cause of AVM pain was neuropathic.

With the application of next-generation sequencing (NGS) in soft tissue tumors, NTRK gene rearrangement is becoming known to pathologists as a molecular hallmark of spindle cell tumors, and other spindle cell tumors with related kinases are being reported. However, cases of RET rearranged spindle cell tumors not associated with NTRK rearrangements are rarely reported. Here, we describe a case of RET rearranged spindle cell tumor in a 3-year-old girl who presented with swelling and pain in the arm. Histologically, the tumor consisted of a fascicular arrangement of monomorphic spindle cells infiltrating and growing in adipose and muscle tissue with visible mitotic activity. Immunohistochemistry showed spindle cells negative for CD34, positive for S100 protein, and focal staining for Pan-TRK. MYH10-RET fusion was identified by NGS. Fluorescence in situ hybridization (FISH) analysis confirmed the RET gene rearrangement but did not detect the NTRK1/2/3 gene rearrangement. In conclusion, we describe a rare case of CD34-negative, S100-positive spindle cell tumor with MYH10-RET fusion.

Endometrial osseous metaplasia is a rare entity encountered in the reproductive age group characterized by the presence of mature bone within the endometrium. Most of the cases are associated with secondary infertility, with a past history of abortion or chronic endometritis. Various hypotheses, such as chronic inflammation, dystrophic calcification, and residual embryonic tissue, have been proposed for the etiopathogenesis. Hysteroscopic removal of the osseous tissue leads to the restoration of normal endometrial function and can potentially resolve infertility. We present a case of a 36-year-old female presenting with abdominal pain. Ultrasonography was suggestive of dystrophic calcification in the endometrium. Bony fragments, along with endometrial curettage material, were removed by hysteroscopy. Histopathology revealed proliferative endometrial glands and stroma admixed with fragments of mature bony trabeculae. A diagnosis of endometrial osseous metaplasia was confirmed. This case report highlights the importance of correctly diagnosing this rare condition on histopathology and differentiating it from other mimics to guide appropriate treatment.

Mucormycosis is a severe invasive infection caused by the Mucorales fungi. The most frequently implicated genera are Rhizopus species, Mucor species, and Lichtheimia species. These fungi do not typically cause infections in immunocompetent individuals. Risk factors include diabetes mellitus, malignancies, transplant recipients, and current or past COVID-19 infection. Mucorales have also been linked to outbreaks in healthcare settings and following natural disasters. We describe a case of rapidly progressing rhinosinusitis in a patient with advanced HIV infection due to Saksenaea oblongispora, a rare cause of mucormycosis that, in contrast to the other Mucorales, primarily affects immunocompetent hosts following traumatic inoculation. A 32-year-old male patient presented with right-sided facial swelling. His clinical condition deteriorated rapidly. Biopsies and computerized tomography (CT) of the brain and sinuses were performed. Tuberculosis and bacterial workups were negative. Histological examination showed thick-walled angioinvasive fungal elements. Fungal cultures were positive. Molecular testing identified the organism as S. oblongispora. Due to his rapid deterioration, he neither underwent surgical intervention nor received any antifungal therapy and subsequently demised. This is the first case of S. oblongispora infection described in sub-Saharan Africa and in the setting of HIV. Infection by this fungus accounts for approximately 3% of human mucormycosis cases. S. oblongispora-associated rhinosinusitis is extremely uncommon and has been associated with rapid progression with high morbidity and mortality. A combination of different testing platforms was required to make a diagnosis. This case emphasizes the challenge of diagnosing invasive mold infections timeously. A high index of suspicion, combined with a multidisciplinary diagnostic and treatment approach, is essential for the management of these infections.