Melanocytic Nevus With Spindle Cell Lipomatous Metaplasia.

ABSTRACT: Melanocytic nevi can show a great number of morphological, cytoarchitectural, and stromal variations. Some of these histopathological patterns, infrequent or unusual, can occasionally produce diagnostic doubts or problems. A 22-year-old female patient presented a poorly pigmented cutaneous polypoid lesion of the scalp. Histopathological examination showed an intradermal melanocytic nevus composed of aggregates, nests, and cords of benign melanocytes, with collagenous stroma and large lipomatous areas. In the lipidized portion of the lesion, nevus cells, arranged in clusters, nests, and cords, were intimately associated with mature-appearing adipocytes, CD34-positive spindle cells, Alcian Blue-positive fibromyxoid stroma, and eosinophilic collagen bundles, findings resembling those typically seen in spindle cell lipoma. Spindle cell lipomatous metaplasia, rarely observed in some benign nonmelanocytic skin lesions, can be considered an additional unusual, not previously described, stromal variation occurring in melanocytic nevi.

Superficial Atypical Lipomatous Tumor With Pleomorphic Features: Case Report and Discussion of the Literature.

ABSTRACT: Among liposarcomas, well-differentiated liposarcoma and dedifferentiated liposarcoma are the most common. The majority of these tumors are found in deep retroperitoneum or extremities. When found outside the retroperitoneum, these adipose-derived tumors are known as atypical lipomatous tumors (ALT). Superficial ALT are particularly rare; thus, little is known about their clinical presentation, genomic status, and management. Here, we present the case of a 54-year-old man with an intermittently bothersome, slowly growing mass on his left upper back for over 2 years, which was incidentally diagnosed as ALT. This patient's ALT, however, showed a profound degree of pleomorphism with MDM2 and control centromere 12 (CEP12) coamplification and negative CD34 and S100 and RB1 expression, unlike most other ALT described in the literature. This case report details the diagnostic workup and histopathological findings for adipose tumors and summarizes the different subtypes, including atypical spindle cell/pleomorphic lipomatous tumor, pleomorphic liposarcoma, and spindle cell/pleomorphic lipoma, with brief discussion on management.

An Atypical Spindle Cell/Pleomorphic Lipomatous Tumor of the Thigh With a Difficult Imaging Diagnosis That Mimicked a Malignant Lipomatous Tumor.

ABSTRACT: Atypical spindle cell/pleomorphic lipomatous tumor is categorized as a benign lipomatous tumor, but various MRI findings pose accurate diagnostic challenges. In our case, both MRI and PET/CT scans indicated the possibility of atypical lipomatous tumor/well-differentiated liposarcoma or dedifferentiated liposarcoma. Needle biopsy suggested benign to low-grade malignancy; hence, we opted for the wide resection. The final diagnosis of atypical spindle cell/pleomorphic lipomatous tumor was confirmed through histopathology analysis, including immunohistochemistry and fluorescence in situ hybridization. Since achieving an accurate diagnosis solely through imaging can be challenging, histopathology remains essential.

Immunohistochemical characteristics of uterine lipoleiomyomas.

Lipoleiomyomas are rare variants of uterine leiomyomas rarely studied in the literature. We retrospectively studied 20 cases of uterine lipoleiomyomas showing that these lesions represent 0.7 % of all uterine leiomyomas diagnosed histologically. The patients did not experience any recurrence, and the tumors showed no morphological criteria of malignancy. They did not show significant p16, p53 or MiB1 expression. They showed diffuse and strong expression or estrogen and progesterone receptors by the smooth muscle component but without accompanying expression by the adipocytic component in one third of the cases. Androgen receptors were rarely expressed. They expressed in their majority HMGA2 in both components, while RB1 was usually not found. Fumarate hydratase (FH) is expressed by lipoleiomyomas, while they are negative for HMB45. In conclusion, uterine lipoleiomyomas are rare, benign tumors, characterized by HMGA2 expression, while they show no elements suspicious of malignancy, PEComas or FH deficiency. The role of RB1 in these tumors should be further explored.

Lingual neoplasia in nonhuman primates: Description of five cases and a literature review.

BACKGROUND: Documentation of lingual tumors is scarce in nonhuman primates. METHODS: Through a multi-institutional retrospective study we compile cases of primary and metastatic neoplasia in non-human primates. RESULTS: We describe five cases of lingual neoplasia. Three cases are primary lingual tumors: chondro-osteoblastic lipoma in a howler monkey, squamous cell carcinoma, and fibroma in two baboons. We describe two cases of metastatic lymphoma in the tongue in rhesus macaques. A literature review of published lingual neoplasia in nonhuman primates is included in this manuscript. CONCLUSION: Lingual neoplasia is seldom reported in non-human primates.

SOLAMEN syndrome with cardiovascular damage.

SOLAMEN syndrome is a rare, recently recognized congenital syndrome that is characterized by progressive and hypertrophic diseases involving multiple systems, including segmental overgrowth, lipomatosis, arteriovenous malformation (AVM) and epidermal nevus. According to literatures, SOLAMEN syndrome is caused by heterozygous PTEN mutation. Phenotypic overlap complicates the clinical identification of diseases associated with PTEN heterozygous mutations, making the diagnosis of SOLAMEN more challenging. In addition, SOLAMEN often presents with segmental tissue overgrowth and vascular malformations, increasing the possibility of misdiagnosis as klipple-trenaunay syndrome or Parks-Weber syndrome. Here, we present a case of a child presenting with macrocephaly, patchy lymphatic malformation on the right chest, marked subcutaneous varicosities and capillaries involving the whole body, overgrowth of the left lower limb, a liner epidermal nevus on the middle of the right lower limb, and a large AVM on the right cranial thoracic entrance. Based on the typical phenotypes, the child was diagnosed as SOLAMEN syndrome. detailed clinical, imaging and genetic diagnoses of SOLAMEN syndrome was rendered. Next-generation sequencing (NGS) data revealed that except for a germline PTEN mutation, a PDGFRB variant was also identified. A subsequent echocardiographic examination detected potential cardiac defects. We suggested that given the progressive nature of AVM and the potential severity of cardiac damage, regular echocardiographic evaluation, imaging follow-up and appropriate interventional therapy for AVM are recommended.

A case of giant labia majora lipoma in an adult.

Lipomas are common benign adipose tissue tumors but are infrequently found in the labia majora, especially at a large size. We report a case of a giant lipoma of the labia majora in a 37-year-old woman diagnosed by imaging methods and successfully treated by surgery. This case highlights the importance of considering lipoma in the differential diagnosis of labial masses and underscores the role of imaging in diagnosis. They need to be differentiated from liposarcoma or omental herniation into Nuck's canal. It also demonstrates the effectiveness of surgical management for large lipomas in sensitive areas, with attention to both medical and aesthetic outcomes.

Corrigendum: Spindle cell lipoma: a rare case report on the hallux.

The original article was published on February 15, 2024 and corrected on April 15, 2024.The revised version of the article corrects Figure 2. The changes appear in the revised online PDF copy of this article.

From Benign Lipoma to G3 Liposarcoma: Contrast-Enhanced Ultrasound Reveals Tumor Microperfusion and Indicates Malignancy.

OBJECTIVE: Lipomatous soft tissue tumors (STT), ranging from benign lipomas to malignant liposarcomas, require accurate differentiation for timely treatment. Complementary to MRI, Contrast-enhanced ultrasound (CEUS) is emerging as a promising tool, providing insight into tumor microperfusion in real-time. This study aims to explore the potential of preoperative CEUS in differentiating benign lipomatous tumors from malignant liposarcoma subtypes. METHODS: Eighty-seven patients with lipomatous STT scheduled for surgery were enrolled. Clinical and MRI assessments were conducted to obtain general tumor characteristics. CEUS was used for a standardized tumor perfusion evaluation. Perfusion analysis included peak enhancement, rise time, wash-in perfusion index, and wash-out rate, reflecting the perfusion kinetics. Histopathological results were obtained for every STT and compared to perfusion characteristics. RESULTS: In total, 48 lipoma, 23 ALT and 11 liposarcoma were identified. Significant differences in tumor microperfusion were demonstrated, with higher perfusion levels indicating higher malignancy (Peak enhancement [a.u.] of Lipoma: 145 ± 238; ALT: 268 ± 368; Liposarcoma: 3256 ± 4333; p (ALT vs. Liposarcoma) < 0.001). A perfusion-based identification of a benign lipoma or ALT versus sarcoma resulted in a positive predictive value of 93%. Patient-related factors (age, gender, BMI, ASA score, smoking status) had no significant impact on the CEUS-based perfusion parameters. CONCLUSION: Our study suggests CEUS as a capable non-invasive tool for improving preoperative assessment of lipomatous STT. It can assist in the distinction between benign and malignant STT, accelerating treatment decisions and enhancing patient outcomes. Significant correlations between CEUS-derived parameters and malignancy highlight its risk assessment potential.

Cord lipoma in minimally invasive surgical repairs of inguinal hernias: a prospective study.

Cord lipomas are frequent findings in laparoscopic inguinal hernia surgeries in male patients. The symptoms of lipoma and the potential benefits of removing them are often overlooked because the focus is on the primary pathology of the hernia itself. Current recommendations are to reduce this fatty content, when present. When inguinal cord lipomas are left untreated in inguinal hernia surgery they can potentially cause symptoms and be detected in follow-up imaging exams. The objective of this study was to study incidence of cord lipomas in a cohort operated on by a single group specializing in abdominal wall surgery, as well as to analyze the possible relationship of this finding with the patient's symptoms, the characteristics of the operated hernia and postoperative outcome. This is a prospective study of male patients operated on for inguinal hernia laparoscopically or robotically in a single reference center. Of the total of 141 hernias, the distribution according to European Hernia Society classification showed that 45.4% were lateral, 19.1% medial and 35.5% mixed, highlighting a variety in the presentation of hernias. Analysis of the size of the hernias revealed that the majority (35.5%) were ≤ 1.5 cm. Inguinal cord lipoma was present in 64.5% of the samples, with no statistically significant association between the presence of the lipoma and an indirect hernia sac or obesity. The incidence of surgical site occurrences (SSO) was 9,2%, with seroma and hematoma. No recurrences were observed during follow-up, indicating a successful approach. There were no statistically significant relationships between SSO, the presence of lipoma and indirect hernial sac.

Incidental Detection of Lipomatous Hypertrophy of the Interventricular Septum on FDG PET/CT.

ABSTRACT: Cardiac lipomatous hypertrophy is a rare benign condition almost exclusively involving the interatrial septum. Interventricular septum involvement is seldom noted, with only a few documented case reports demonstrating the finding on various modalities such as ECHO, CT, and MRI. FDG PET can be a surrogate marker for lipomatous hypertrophy of the interventricular septum. Here, we describe a case of incidentally detected lipomatous hypertrophy of the interventricular septum on FDG PET/CT in a patient with squamous cell carcinoma of the oropharynx.

Clinical course of asymptomatic duodenal subepithelial lesions.

BACKGROUND/AIMS: There is limited knowledge regarding the management of duodenal subepithelial lesions (SELs) owing to a lack of understanding of their natural course. This study aimed to assess the natural course of asymptomatic duodenal SELs and provide management recommendations. METHODS: Patients diagnosed with duodenal SELs and followed up for a minimum of 6 months were retrospectively investigated. RESULTS: Among the 443,533 patients who underwent esophagogastroduodenoscopy between 2008 and 2020, duodenal SELs were identified in 0.39% (1,713 patients). Among them, 396 duodenal SELs were monitored for a median period of 72.5 months (interquartile range, 37.7-111.3 mo). Of them, 16 SELs (4.0%) showed substantial changes in size or morphology at a median follow-up of 35.1 months (interquartile range, 21.7-51.4 mo). Of these SELs with substantial changes, tissues of two SELs were acquired using endoscopic ultrasound-guided fine needle aspiration biopsy: one was a lipoma and the other was non-diagnostic. Three SELs were surgically or endoscopically removed; two were diagnosed as gastrointestinal stromal tumors, and one was a lipoma. An initial size of 20 mm or larger was associated with substantial changes during follow-up (p = 0.016). CONCLUSION: While the majority of duodenal SELs may not exhibit substantial interval changes, regular follow-up with endoscopy may be necessary for cases with an initial size of 20 mm or larger, considering a possibility of malignancy.

Fibrolipoma of the lower lip: A case report and review of the literature.

BACKGROUND: Fibrolipoma of the lower lip is an uncommon condition with limited documentation in the literature. This paper provides updated insights into oral and maxillofacial lipomas through a detailed case report and comprehensive literature review, discussing clinical features, pathogenesis, diagnostic approaches, histopathology, and therapeutic strategies. CASE PRESENTATION: A 54-year-old female presented with a painless, enlarging mass on the inner aspect of her right lower lip, first noticed 2 years prior. The mass, now the size of a peanut, interfered with her eating and speech. Physical examination revealed a 2.0 × 2.5 × 1.0 cm mass beneath the mucous membrane of the right lower lip. It was firm, well-demarcated, and mobile. Surgical excision was performed, and histopathological analysis confirmed the diagnosis of a lower lip fibrolipoma. The lesion was successfully removed without recurrence. CONCLUSION: Lipomas in the oral and maxillofacial regions are rare, slow-growing benign tumors, particularly within the lips. Although their diagnosis is straightforward based on clinical presentation, histopathological confirmation is essential. Surgical resection remains the treatment of choice, with excellent prognostic outcomes.

Lipomatoses.

Lipomatoses are benign proliferation of adipose tissue. Lipomas (benign fat tumors) are the most common component of lipomatosis. They may be unique or multiple, encapsulated or not, subcutaneous or sometimes visceral. In some cases, they form large areas of non-encapsulated fat hypertrophy, with a variable degree of fibrosis. They can develop despite the absence of obesity. They may be familial or acquired. At difference with lipodystrophy syndromes, they are not associated with lipoatrophy areas, except in some rare cases such as type 2 familial partial lipodystrophy syndromes (FPLD2). Their metabolic impact is variable in part depending on associated obesity. They may have functional or aesthetic consequences. Lipomatosis may be isolated, be part of a syndrome, or may be visceral. Isolated lipomatoses include multiple symmetrical lipomatosis (Madelung disease or Launois-Bensaude syndrome), familial multiple lipomatosis, the painful Dercum's disease also called Adiposis Dolorosa or Ander syndrome, mesosomatic lipomatosis also called Roch-Leri lipomatosis, familial angiolipomatosis, lipedema and hibernomas. Syndromic lipomatoses include PIK3CA-related disorders, Cowden/PTEN hamartomas-tumor syndrome, some lipodystrophy syndromes, and mitochondrial diseases, especially MERRF, multiple endocrine neoplasia type 1, neurofibromatosis type 1, Wilson disease, Pai or Haberland syndromes. Finally, visceral lipomatoses have been reported in numerous organs and sites: pancreatic, adrenal, abdominal, epidural, mediastinal, epicardial… The aim of this review is to present the main types of lipomatosis and their physiopathological component, when it is known.

Metastasis of Rectal Signet Ring Cell Carcinoma to Typical Lipoma: A Rare Presentation of the Tumor-to-Tumor Metastasis Phenomenon.

Rectal signet ring cell carcinoma represents a rare subtype of colorectal adenocarcinoma known for its aggressive biological nature and poor prognosis. Although the co-occurrence of colorectal carcinoma with other tumors has been reported, the uncommon phenomenon of tumor-to-tumor metastasis, first described in 1930, remains rare. The most frequent donor neoplasms are lung or breast carcinomas, whereas cerebral meningiomas have been reported to be the most frequent recipient neoplasms. Here we report a case of a typical lipomatous tumor harboring metastatic signet ring cell rectal carcinoma. It is about a 42-year-old man diagnosed with rectal signet ring cell carcinoma and treated with concurrent radiotherapy and chemotherapy followed by an anterior resection and manual coloanal anastomosis with a temporary ileostomy. During the surgery, an abdominal wall lipoma was discovered and excised. A histopathological examination revealed infiltration of the fibro adipose tissue by a mucinous adenocarcinoma with a contingent of signet ring cells. The patient died 12 months after adjuvant chemotherapy due to peritoneal progression. To the best of our understanding, this represents the initial documented instance of tumor-to-tumor metastasis from rectal signet cell carcinoma to a conventional nonvascular lipoma. Consequently, even if one of these tumors appears clinically and radiologically benign, it is prudent to entertain the prospect of tumor-to-tumor metastasis. Thus, a comprehensive pathologic study of both tumors is highly recommended.

Large atypical lipomatous tumour of the neck with mediastinal extension managed by transcervical excision.

Tumours of adipose tissue origin are relatively rare in the head and neck. Here, we report a case of an unfamiliar lipomatous lesion that involved the neck and mediastinum. A nil-comorbid man in his 40s presented with a slowly progressive anterior neck swelling of 3 years, which was diagnosed as lipoma by histopathological sampling. Computed tomography demonstrated the lesion to be involving parapharyngeal and retropharyngeal spaces with mediastinal extension. The lesion was removed by the transcervical approach. The final histology of the excised specimen, with immunohistochemistry for mouse double minute 2 (MDM2) and p16, suggested an atypical lipomatous tumour (ALT). This report accentuates the occurrence of this rare neoplasm in the neck, which often mimics lipoma clinically. Although radiology can demonstrate suggestive features, histology with MDM2 and/or p16 positivity can confirm the diagnosis of ALT as against the lipoma. A successful transcervical excision, despite the deeper extension of the lesion between the critical structures of the neck and mediastinum, demonstrates the non-infiltrating nature of the tumour.