Benign female genital tract smooth muscle tumors with adipocytic differentiation: A morphologic, immunohistochemical and MDM2 fluorescence in situ hybridization study of 44 conventional lipoleiomyomas and lipoleiomyoma variants

Leiomyomas with adipocytic differentiation typically occur in the uterus although they may arise at several sites in the female genital tract. While these are most commonly spindled leiomyomas with a component of adipocytic tissue ("conventional lipoleiomyomas"), there is a relatively ill-defined assortment of leiomyoma variants with adipocytic differentiation. We performed a morphologic, immunohistochemical and MDM2 gene amplification analysis of a large series of gynecologic leiomyomas with adipocytic differentiation to better define the clinicopathologic spectrum. Forty four tumors from 44 patients were identified and classified as conventional lipoleiomyoma (n = 21), adipocyte-rich lipoleiomyoma (defined as tumor volume >80 % adipocytes, n = 9); cellular lipoleiomyoma (n = 9); hydropic lipoleiomyoma (n = 3); and lipoleiomyoma with bizarre nuclei (n = 2). Patient age ranged from 32 to 83 years (mean 63; median 63). Primary location included uterine corpus (35), uterine cervix (3), uterine corpus/cervix (1), broad ligament (2), parametrium (2), and round ligament (1). Tumor size was 0.6-30 cm (mean 8; median 6). None of the 34 patients with follow up developed further disease (range 1-311 months; mean 65; median 41). Immunohistochemical expression of ER, PR, HMB45, Melan A, Cathepsin K and WT-1 in lipoleiomyomas and variants was similar to patterns in non-adipocytic gynecologic leiomyomas. MDM2 amplification fluorescence in situ hybridization performed on 14 tumors was negative in all. Our findings suggest female genital tract conventional lipoleiomyomas and lipoleiomyoma variants largely parallel their non-adipocytic counterparts in morphology and immunophenotype, and may be categorized using non-adipocytic leiomyoma histologic criteria.

Top 10 Significant Spindled Head and Neck Lesions to Scrutinze

BACKGROUND

Spindled lesions are a challenging area in head and neck pathology. This is particularly true in the sinonasal tract, where several uncommon entities with both unique and overlapping morphologic, immunophenotypic, and/or molecular features can occur.

METHODS

Review.

RESULTS

The clinicopathologic characteristics of biphenotypic sinonasal sarcoma and nine important differential diagnostic considerations with one or more overlapping feature are summarized to establish a practical framework for approaching spindled lesions of the sinonasal tract.

CONCLUSION

Morphologic evaluation is central to the work up of sinonasal spindle cell lesions-in particular, cellular morphology, tumor architecture and growth pattern, and the presence of admixed epithelial elements - however, focused immunohistochemical analysis of neural, myogenic, rhabdomyoblastic, epithelial, and/or melanocytic marker expression and/or ancillary tests for tumor-specific molecular alterations may be necessary for definitive diagnosis.

Benign and malignant proliferation in idiopathic nephrotic syndrome: a French cohort study

BACKGROUND

There seems to be a possible link between nephrotic syndrome (NS) and lymphoproliferative syndrome, but it remains poorly understood.

METHODS

This multicentric and retrospective study focuses on children, who developed idiopathic NS and malignant or benign proliferation between 2000 and 2021.

RESULTS

Eleven patients were included, with a median age of 4 years. Only one had a steroid-resistant nephrotic syndrome (SRNS). The maintenance therapy before the proliferation was in majority tacrolimus or mycophenolate mofetil (MMF), but three patients did not receive treatments. The proliferation was mainly a Hodgkin's lymphoma (45%) or a lymphoproliferative disease (36%), in a median time after the NS of two years. Viruses were found in seven cases (EBV in five cases and HHV-8 in two).

CONCLUSION

The association between proliferative syndrome and idiopathic NS may not be fortuitous, possibly with a common lymphocytic disturbance. Genetic analyses could improve the comprehension of these manifestations in the future. A higher resolution version of the Graphical abstract is available as Supplementary information.

[Leiomyosarcoma of the nasal fossa. A case report]

A 54-year-old female patient presented with a left nasal obstruction. On physical examination a pink delimited mass in the left nostril was observed. A cranial computed tomography scan revealed an expansive mass in the upper anterior third of the left nasal fossa, partially obstructing it. Endoscopic resection of the mass was performed. Histopathology revealed an atypical mesenchymal proliferation formed by cells disposed in disorganized and interconnected long bundles. Tumor cells had abundant eosinophilic cytoplasm and an oval, vesicular and hyperchromatic nucleus. Frequent mitotic figures were observed, many of them atypical. Necrosis was not observed. Immunohistochemistry showed tumor cells to be positive for calponin, muscle specific actin, caldesmon and smooth muscle specific myosin. Ki-67 index proliferation was 30%. A diagnosis of leiomyosarcoma of the nasal fossa was established.

Epstein-Barr virus-associated smooth muscle tumors in immunocompromised patients: Six case reports

BACKGROUND

Epstein-Barr virus associated smooth muscle tumor (EBV-SMT) is a rare oncological entity. However, there is an increasing incidence of EBV-SMTs, as the frequency of organ transplantation and immunosuppression grows. EBV-SMT diagnosis relies on histopathology and immunochemical staining to distinguish it from post-transplant lymphoproliferative disorder (PTLD). There is no clear consensus on the treatment of EBV-SMTs. However, surgical resection, chemotherapy, radiation therapy, and immunosuppression reduction have been explored with varying degrees of success.

CASE SUMMARY

Our case series includes six cases of EBV-SMTs across different age groups, with different treatment modalities, adding to the limited existing literature on this rare tumor. The median latency time between immunosuppression and disease diagnosis is four years. EBV-SMTs present with variable degrees of aggressiveness and seem to have worse clinical outcomes in patients with tumor multiplicity and worse immunocompetency.

CONCLUSION

It is imperative to continue building on this knowledge and keeping EBV-SMTs on the differential in immunocompromised individuals.

Histiocyte-rich rhabdomyoblastic tumor: a report of two cases and a review of the differential diagnoses

Histiocyte-rich rhabdomyoblastic tumor is a recently described skeletal muscle neoplasm of uncertain malignant potential, characterized by slow growth, a fibrous capsule containing peripheral lymphoid aggregates, spindle-to-epithelioid cells with a rhabdomyoblastic immunophenotype, and a dense histiocytic infiltrate. It most commonly arises within the muscles of the lower legs and trunk in young-to-middle-aged men, and initial reports suggest indolent behavior. In this paper, we present two additional cases of histiocyte-rich rhabdomyoblastic tumor with similar clinicopathologic features and discuss the differential diagnosis including its overlap with inflammatory leiomyosarcoma.

Inflammatory leiomyosarcoma shows frequent co-expression of smooth and skeletal muscle markers supporting a primitive myogenic phenotype: a report of 9 cases with a proposal for reclassification as low-grade inflammatory myogenic tumor

Inflammatory leiomyosarcoma (ILMS) is a very rare soft tissue tumor that usually follows an indolent clinical course, but long-term follow-up studies are lacking. Recent publications primarily focused on its genetic profile characterized by a near haploid genome. One study also showed these tumors to have upregulation of genes known to be crucial for skeletal muscle differentiation. Nevertheless, immunohistochemical expression of skeletal muscle markers, as well as markers that would help to distinguish ILMS from a long list of relevant differential diagnostic entities, has not been extensively studied. Nine cases of ILMS were collected and stained by a broad IHC panel which, besides others, contained MyoD1, myogenin, and PAX-7. A subset of cases was also analyzed by 2 different NGS assays and by MDM2 fluorescence in situ hybridization. Five male and 4 female patients ranged in age from 25 to 54 years (mean, 36 years). The tumors showed a predilection for intramuscular sites of the lower limbs (n = 4) and back (n = 2), whereas the remaining 3 cases affected an unspecified skeletal muscle, lung, and omentum. Follow-up with an average length of 10.6 years (range 0.5-22) was available for 8 patients. The omental tumor spread locally within the abdominal cavity, but the patient has been free of disease 7 years after treatment. None of the 5 patients with somatic soft tissue tumors (and follow-up longer than 1.5 years) had either recurrence or metastasis. Immunohistochemical studies revealed a substantial expression of skeletal muscle markers in almost all cases. This phenotype coupled with a highly characteristic genotype and significantly more indolent clinical behavior as compared with conventional leiomyosarcoma of deep soft tissue offers a strong rationale to change the current nomenclature. Based on the clinicopathological features and gene expression profile, we propose the name low-grade inflammatory myogenic tumor.

[Intravenous leiomyomatosis]

Intravenous leiomyomatosis (IVLM) is an unusual neoplasm derived from uterine smooth muscle cells seen in patients with uterine leiomyomas. The typical histological features of IVLM consist of benign smooth muscle cells present within venous vascular spaces of the uterine wall. Increasing intravascular and intracardial spread of IVLM may lead to life-threatening clinical complications. Thorough pathological study of routine hysterectomy specimens may lead to the diagnosis of IVLM. Most affected patients will be cardiologically asymptomatic at the time of diagnosis. Herein, the relatively unknown clinical and morphological aspects of IVLM are presented and discussed.

Immunohistochemical Profile of Uterine Leiomyoma With Bizarre Nuclei; Comparison With Conventional Leiomyoma, Smooth Muscle Tumors of Uncertain Malignant Potential and Leiomyosarcoma

PURPOSE

To assess the immunohistochemical profile of the atypical nuclei in leiomyoma with bizarre nuclei and compare with benign and malignant counterparts.

METHODS

26 cases of uterine smooth muscle tumors including 12 leiomyosarcoma(LMS), 10 leiomyoma with bizarre nuclei (LBN) and 4 smooth muscle tumor with uncertain malignant potential (STUMP) were selected using whole tissue sections for this study and analysis. Six cases of ordinary leiomyoma were included as benign control group. All representative section were stained for P53, Ki67, estrogen receptor and progestrone receptor. Analysis was carried out using SPSS 16.0 for windows software.

RESULTS

Six out of 12 cases of LMS showed strong and diffuse nuclear staining with p53 antibody (50%). In contrast none of STUMPs and only one case of LBN cases showed focal positive reaction with P53. Percentage of positive cells for ki67 in LMS was 14.92 while only 0.85% of cells in LBNs was labeled with Ki67 proliferative marker. (P<0.001). Regarding steroid hormone receptors a significant loosing trend was found in these receptors from benign toward malignant tumors through LBN and STUMP cases.

CONCLUSION

Loss of inhibitory function of wild type P53 gene in leiomyosarcoma is an essential event that discriminate frankly malignant tumors from STUMP and atypical leiomyoma.

An unusual karyotype in leiomyoma: Case report and literature review

Vascular leiomyoma are uncommon, clinically benign smooth muscle tumors. Here we report a case of an otherwise typical leiomyoma with unusual cytogenetic changes including t(1;10). Reports from the existing literature suggest that approximately 40-50% of leiomyomas contain nonrandom chromosomal abnormalities of which a subset is tumor specific. t(12;14)(q15;q24) is one of the most common translocations, which occur in approximately 20% of karyotypes. Additional aberrations include del(7)(q22-q32), trisomy 12, and 6p21 rearrangements. Other recurrent abnormalities include monosomy 22, monosomy 10, del(10q), and structural rearrangements of chromosome 3.

Successful pregnancy following myomectomy for uterine smooth muscle tumor of uncertain malignant potential: A case report and review of the literature

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STUMPs are rare smooth muscle tumors with an overall favorable prognosis.

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Pregnancy is possible after diagnosis of STUMP treated with myomectomy

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Management of patients desiring fertility with STUMPs requires a multidisciplinary approach.