Myoid Gonadal Stromal Tumor: A New Case Report with a Review of the Literature

The myoid gonadal stromal tumor is a very rare testicular spindle cell tumor. Few cases have been reported in the literature from 1977 to 2022. It was an emerging entity in the fourth edition of the WHO Classification of Tumors of the Urinary System and Male Genital Organs and has been instated as a full benign entity in the new edition of 2022. We report herein an additional case of a myoid gonadal stromal tumor. It was a 27-year-old man who presented with an asymptomatic mass in his left testicle for 2 months. The mass was confirmed by ultrasound as a 3 cm solid well-circumscribed lesion for which orchiectomy has been performed. The histological analysis of the specimen and the immunohistochemistry staining was consistent with a myoid gonadal stromal tumor. The characteristics of this tumor are summarized in well-circumscribed, nonencapsulated masses of uniform spindle cells, and immunohistochemically, tumor cells coexpress SMA and S-100 protein. The benign behavior of this tumor is demonstrated by our results and those presented in the previous cases reported in the literature.

Solitary Fibrous Tumor of Breast and Axilla: Clinicopathological Profile of Five Tumors With Comparison of Risk Stratification Models

Introduction: Solitary fibrous tumor (SFT) is a fibroblastic tumor with malignant potential that is underpinned by a recurrent inv12(q13q13)-derived NAB2::STAT6 fusion. Breast and axilla are uncommon locations for this entity. Methods: Records of two academic institutions were electronically searched for breast and axillary SFTs. Clinical and pathologic data were reviewed. Literature review for breast or axillary SFTs was performed. Present study and previously reported tumors were stratified using five SFT risk models: original and modified Demicco metastatic risk, Salas local recurrence risk, Salas metastatic risk, and Thompson local recurrence risk. Results: Five patients with breast or axillary SFT were identified. Median age was 49 years, and median follow-up (available for four patients) was 82 months. Three patients showed no evidence of disease, and one developed recurrence. Literature review identified 58 patients with breast or axillary SFT. Median age was 54 years, and median follow-up (available for 35 patients) was 24 months. Thirty-one patients showed no evidence of disease, three developed recurrence, and one developed metastasis. Original and modified Demicco models and Thompson model showed the highest sensitivity; original and modified Demicco models and Salas metastatic risk model demonstrated the highest specificity. Kaplan-Meier models were used to assess recurrence-free probability (RFP). Original and modified Demicco models predicted RFP when stratified by "low risk" and "moderate/intermediate and high risk" tumor, though sample size was small. Conclusions: While many SFTs of breast and axilla remain indolent, a subset may develop recurrence and rarely metastasize. The modified Demicco risk model demonstrated optimal performance characteristics.

Mesenchymal Tumors of the Breast: Fibroblastic/Myofibroblastic Lesions and Other Lesions

Mesenchymal breast tumors are a rare and diverse group of tumors that present some of the most challenging cases for multidisciplinary breast cancer teams. As a result of overlapping morphologies and a lack of large-scale studies on these tumors, practices are often heterogeneous and slow to evolve. Herein, we present a non-systematic review that focuses on progress, or lack thereof, in the field of mesenchymal breast tumors. We focus on tumors originating from fibroblastic/myofibroblastic cells and tumors originating from less common cellular origins (smooth muscle, neural tissue, adipose tissue, vascular tissue, etc.).

Gastrointestinal Stromal Tumors (GIST): A Population-Based Study Using the SEER Database, including Management and Recent Advances in Targeted Therapy

Introduction: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal (GI) system. Most GISTs originate from the interstitial cells of Cajal (ICC), the pacemaker cell situated between the circular and longitudinal layers of the muscularis propria along the GI tract. In this population-based study using the SEER database, we sought to identify demographic, clinical, and pathologic factors that affect the prognosis and survival of patients with this neoplasm. Molecular genetic advances, current management guidelines, and advances in targeted therapy are discussed. Methods: Demographic and clinical data from GIST patients were retrieved from the SEER research plus database for the period 2000−2018. Statistical analysis was performed with IBM SPSS® v20.2 software using the Chi-square test, paired t-test, multivariate analysis, and Kaplan−Meier functions. Results: A total of 10,833 patients with GIST were identified. Most patients were between 60−74 years of age: 40%, Caucasian: 68%, and the male to female ratio was 1.1:1. The most common primary tumor sites were stomach: 63%, small intestine: 30%, rectum: 3%, and esophagus: 0.7%. When reported, the grade of differentiation was well: 38%, moderately: 32%, undifferentiated: 19%, poorly: 12%. The size of most tumors ranged between 6−10 cm: 36% and they were treated by surgical intervention: 82% and/or chemotherapy/targeted therapy: 39%. The stage was localized: 66%, advanced: 19%, and regional: 15%. The 5-year survival was 74% (95% confidence interval (95% CI) = 72.6−74.7), and the 5-year cause-specific survival 82% (95% CI = 80.7−82.6). The 5-year cause-specific survival by treatment included surgery at 86% (95% CI = 85.4−87.3), chemotherapy/targeted therapy with or without surgery at 77% (95% CI = 75.7−78.9), and radiation at 75% (95% CI = 74.5−80). On multivariable analysis tumor size > 5 cm, poorly and undifferentiated grade, age > 60, and distant metastases at presentation were associated with worse overall survival. Conclusion: GISTs comprise 1−2% of malignancies of the GI tract, usually affect male Caucasians between the ages of 60 and 74 years, most tumors occur in the stomach and small intestine, and are usually >5 cm, but still localized, at the time of diagnosis. Most tumors receive multimodality surgical and chemotherapy/targeted therapy treatment, with a 5-year overall survival of 74% and cause-specific survival of 82%. GIST patients would benefit from enrollment in large clinical trials to establish better therapy guidelines for unresectable, treatment-refractory, and recurrent tumors.

Hemangiomatous Ameloblastoma with Spindle Cell Proliferation: A Rare Case Report and Review of Literature

Ameloblastoma is a locally aggressive neoplasm with varied histological patterns. The histomorphologic variants of ameloblastoma bear no prognostic or biologic behavioral significance with possible exceptions of desmoplastic and hemangioameloblastoma. The present paper aims at reporting a case of 38-year-old male with a huge lesion present in the mandibular symphysial region crossing the midline, histopathologically showing hemangiomatous component in follicular and plexiform ameloblastoma along with spindle cell differentiation in the ameloblastic follicles. Spindle cell differentiation in ameloblastoma is rarely reported and the prognostic significance is yet not clear. The present paper also reviews the literature since the diagnosis of this lesion is must as it may lead to surgical complications.

Malignant spindle cell tumors of the posterior fossa in children: case series and review of management

OBJECTIVE

The WHO Classification of Tumours of the Central Nervous System (2016) classifies nonmeningothelial malignant spindle cell tumors involving the extraaxial tissues of the posterior fossa as melanocytic tumors and malignant mesenchymal tumors (sarcomas). The objective of this study was to conduct a review of the literature pertaining to the management strategies of posterior fossa malignant spindle cell tumors in the pediatric population.

METHODS

The authors performed an institutional search of their pathology database for patients younger than 18 years of age who presented with posterior fossa malignant spindle cell tumors. A literature review was also performed using the PubMed database, with "posterior fossa" or "spindle cell tumors" or "Ewing sarcoma" or "high-grade" or "spindle cell sarcoma" or "leptomeningeal melanocytoma" as keywords. The database search was restricted to pediatric patients (age ≤ 18 years). Parameters reported from the literature review included patient age, tumor location, presenting symptoms, treatment modalities (resection, chemotherapy, and/or radiotherapy), leptomeningeal spread at or after the time of treatment, and follow-up length and resulting outcome.

RESULTS

The authors report 3 rare cases of posterior fossa malignant spindle cell tumors, including Ewing sarcoma in a 13-year-old male; high-grade spindle cell sarcoma, not otherwise specified in a 10-year-old male; and primary leptomeningeal melanocytoma in a 16-year-old female. All 3 patients underwent resection and radiotherapy and either chemotherapy or targeted immunotherapy. At the last follow-up, all patients were alive with either resolution or stable disease.

CONCLUSIONS

A review of these 3 cases and the existing literature support managing patients with intracranial malignant spindle cell tumors with multimodal therapy that can include a combination of resection, radiotherapy, and chemotherapy or immunotherapy to prolong progression-free and overall survival.

Dermatofibrosarcoma protuberans of the breast: A case study

Dermatofibrosarcoma protuberans (DFSP) is a superficial mesenchymal neoplasm that originates from the dermal fibroblasts and tends to be locally aggressive. Although infrequent, it is one of the most common cutaneous sarcomas. It mainly affects young and middle-aged patients 20 to 50 years old. Any area of skin may be involved, but the most common sites of presentation are the trunk and extremities. DFSP of the breast is extremely rare. It classically presents as a nodular, exophytic, cutaneous mass, though initially it can manifest as a flat plague and can show persistent but slow growth for many years. Due to increased risk of local recurrence, the standard of care for localized disease is surgical excision with adequate margins. Wide local excision is the most common technique used, but as an alternative Mohs micrographic surgery has emerged as a procedure that offers lower local recurrence rates. Metastases are rare but have been previously reported. In such patients, treatment with imatinib or radiotherapy can be considered. The current case presents a 52-year-old lady with DFSP of the breast that was successfully managed by the Breast Unit of Athens Medical Center-Psychiko Clinic.

Novel PPP1CB-ALK fusion in spindle cell tumor defined by S100 and CD34 coexpression and distinctive stromal and perivascular hyalinization

A novel group of S100- and CD34-positive spindle cell tumors with distinctive stromal and perivascular hyalinization harboring recurrent gene fusions involving kinases including RAF1, BRAF, NTRK1/2/3, and RET have been recently reported. To our knowledge, no such cases harboring ALK rearrangements have been identified. We report a previously healthy 41-year-old male with a 12-cm intramuscular shoulder mass. The tumor was composed of bland-appearing spindled to epithelioid cells, arranged in a patternless pattern in a background of loose myxoid stroma containing striking amianthoid-like stromal collagen and perivascular rings. In accordance with the previously reported tumors, the tumor cells showed diffuse immunopositivity with S100 and CD34, while lacking SOX10 expression. Targeted RNA-based next-generation sequencing identified a novel serine/threonine-protein phosphatase PP1-beta-catalytic subunit (PPP1CB)-ALK fusion gene. Although ALK break-apart was not detected by FISH, likely due to a paracentric inversion of chromosome 2, the presence of the fusion was confirmed by Sanger sequencing showing a 10-bp linker between exon 6 of PPP1CB and intron 19 of ALK while maintaining reading frame. Subsequent ALK-1 immunostain exhibited diffuse cytoplasmic staining in the tumor cells. Our case expands the molecular genetic spectrum of the distinctive group of spindle cell tumors with CD34/S100+ immunophenotype, supporting the important role of various kinases as drivers of oncogenesis. Awareness of this entity including its unique morphologic and immunophenotypic features as well as its interchangeable kinase gene fusions is crucial for correct classification and potential targeted therapy, particularly in aggressive subsets.

Gastrointestinal stromal tumor presenting as a rectovaginal septal mass: A case report and review of literature

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) arising from the gynecological tract are extremely rare. A case of GIST with an unusual presentation as a vaginal mass is presented with comprehensive literature review, aiming to gain a better understanding of the diagnostic and treatment strategy of the disease.

PATIENT CONCERNS

A 78-year-old woman presented with persistent vaginal bleeding and difficulty in micturition. Although the tumor mass was diagnosed, the results of preoperative evaluations are uncertain.

DIAGNOSIS

Preoperative evaluation included the computed tomography examination (a 6.3×5.3 cm cervical mass lesion with rectal and vaginal invasion), colonoscopy (an external compression with an intact mucosa), tumor markers, and biopsy (spindle cell tumor). Postoperative histopathology confirmed the diagnosis of GIST.

INTERVENTIONS

Posterior exenteration with complete resection was performed. The patient received postoperative adjuvant imatinib therapy.

OUTCOMES

The patient has survived without the disease for more than 3 years.

CONCLUSION

It is still a challenge to diagnose GISTs in women with rectovaginal mass preoperatively. Efforts should be made, including a high suspicion and an assistance of immunohistochemistry. A precise diagnosis may offer a better surgical and treatment plan, especially on the preservation of reproductive organs and accessibility of targeted therapy.

Cutaneous ganglioneuroma: A case report and discussion of the literature

Ganglioneuromas (GNs) are benign tumors composed of ganglion cells in a Schwannian stroma. They are derived from neural crest cells that give rise to the sympathetic nervous system. Hence, GNs can be found anywhere a sympathetic ganglion is present. Most commonly, GNs are found in the posterior mediastinum and abdominal cavity. Within the abdominal cavity, they are most likely to be found in the retroperitoneal space or adrenal glands. Cutaneous involvement is uncommon and rarely reported in literature. We report an interesting case of a cutaneous ganglioneuroma on the abdomen of an 83-year-old male.

Clinicopathological features of primary thyroid leiomyosarcoma without Epstein-Barr virus infection: A case report

Primary thyroid leiomyosarcoma (LMS) is a rare tumor type with an unusual location, the diagnosis is based entirely on histological and immunohistochemical evaluations. In the present study, a rare case of a 74-year-old female patient who exhibited a right anterior neck mass for 12 months, which rapidly enlarged for the last 3 months. Ultrasound of the thyroid revealed a 55×42 mm hypoechoic mass with clear margins in the right lobe. Histological examination of the tumor demonstrated malignant spindle cells in interlacing fascicles and whorls. Additionally, nuclear pleomorphism, tumor giant cells, necrosis and abnormal mitotic figures were observed. The immunohistochemistry indicated that the tumor cells were strongly positive for smooth muscle actin, desmin, p53 and vimentin expression, but negative for cytokeratin, epithelial membrane antigen, thyroid transcription factor-1, paired box-8, 34βE12, cytokeratin 5/6, cluster of differentiation (CD)117, myoglobin, S100, p16. The final histopathological diagnosis was primary thyroid LMS.

Sarcomatoid (spindle cell) carcinoma of the head and neck mucosal region: a clinicopathologic review of 103 cases from a tertiary referral cancer centre

Sarcomatoid carcinomas are biphasic tumors proven to be monoclonal dedifferentiated forms of conventional squamous carcinomas. This study evaluates their clinicopathologic characteristics in head and neck mucosal sites and the problems in distinguishing them from other spindle cell tumors. A total of 103 cases with a confirmed diagnosis of sarcomatoid carcinoma accessioned in the pathology department of a tertiary referral cancer centre over a period of 7 years (2004-2010) were studied. An algorithm used for their diagnosis is presented. Ages of the patients were 22-90 years (median 53 years), and male:female ratio was 3.7:1. Site distribution was oral cavity (n = 65, 63.1%), larynx (18, 17.5%), oropharynx/hypopharynx (12, 10.7%), maxilla (6, 5.8%) and metastatic nodes (2, 1.9%). A large number of patients (95%) presented with a mass lesion of less than 1 year duration. Histopathologically, epithelial differentiation was evident on morphology in 48 (46.6%) cases, only on IHC in 34 (33%) cases, and in 21 (20.4%) no epithelial differentiation was seen. Typically, tumors were polypoidal (92, 89.3%) and ulcerated (95, 92.2%) with cells arranged predominantly in fascicles (59, 57.3%) or storiform pattern (17, 16.5%) amidst collagenous (50, 48.5%) or myxoid matrix (35, 34%). Anaplasia (2+/3+) and mitosis >10 per 10 HPF were noted in 96 (93.2%) cases. IHC was done in 82 cases; 55 (66.7%) showed positivity for epithelial markers with aberrant expression of mesenchymal markers in 43 (41.7%). Diagnosis of sarcomatoid squamous carcinoma is challenging because of overlapping histopathological features with other spindle cell tumors. Understanding their clinicopathologic characteristics facilitates their diagnosis and appropriate clinical management.