Recurrent high-grade leiomyosarcoma with heterologous osteosarcomatous differentiation

Primary leiomyosarcoma with osteosarcomatous differentiation of the breast

Primary leiomyosarcoma with osteosarcomatous differentiation of the breast is an uncommon entity. We present the case of a 37-year-old female who presented with a lump in the breast and pulmonary lesions on PET-CT, for which she underwent a toilet mastectomy. Histopathological examination revealed a tumor with cells arranged in sheets. These tumor cells had moderate eosinophilic cytoplasm, highly pleomorphic, irregular hyperchromatic nuclei, coarse chromatin, and prominent nucleoli. Areas with spindle-cell morphology were noted. Osteoid was seen intermingling with the tumor along with numerous osteoclast-like multinucleate giant cells. A wide panel of Immunohistochemistry was applied, and Desmin, h-Caldesmon, SMA, and Vimentin were positive. The patient died 3 months post-surgery and had a recurrence at the surgical site.

A Humeral Osteosarcoma Mimicking Osseous Leiomyosarcoma: A Case Report

Osteosarcoma stands as one of the primary mesenchymal bone neoplasms commonly encountered in clinical practice. This malignancy often presents with a wide range of distinctive imaging characteristics. Here, we present a unique case wherein a delayed diagnosis of high-grade osteosarcoma occurred due to the absence of an osteoid matrix in the initial imaging studies. A 61-year-old female, initially presented with a left humeral fracture. As the healing of the fractured bone was delayed and the possibility of a pathologic fracture was considered, a CT-guided biopsy was performed. Histological examination of the biopsy sample initially suggested an osseous leiomyosarcoma. The lack of osteoid matrix on radiographs including aggressive intra-medullary mass seen on MRI, combined with the patient's age, appeared consistent with a diagnosis of leiomyosarcoma of bone. As a result, the initial diagnosis was not called into question. Due to neurovascular involvement, this led to a forequarter amputation. However, upon microscopic examination of the amputation specimen, certain areas exhibited features indicative of malignant osteoid deposition, ultimately supporting a revised diagnosis of high-grade osteosarcoma. This case underscores the critical importance of considering the limitations of core biopsy samples, especially when dealing with suspected limb masses associated with pathological fractures. Radiographs and CT scans can prove invaluable in ruling out subtle adjacent osteoid, and ultimately a multidisciplinary approach to the diagnosis of osteosarcoma is imperative to ensure accurate identification.

Metastatic Uterine Leiomyosarcoma With Rhabdomyosarcomatous Heterologous Differentiation

Heterologous differentiation has only been previously reported twice in metastatic uterine leiomyosarcomas. We report herein the first case of metastatic uterine leiomyosarcoma with rhabdomyosarcomatous differentiation. A 67-yr-old woman presented with femur, abductor magnus, and lymph node metastases 9 yr after the primary diagnosis. The metastatic sites showed rhabdomyosarcomatous morphologic features, and immunohistochemical studies confirmed skeletal muscle differentiation. Molecular testing revealed the same loss-of-function TP53 mutation in the uterine leiomyosarcoma and metastatic sites supporting heterologous differentiation of the primary tumor. Our case highlights the morphologic shifts metastatic tumors may manifest and the potential diagnostic problems that may arise.

Dedifferentiated leiomyosarcoma of the uterus: a clinicopathologic and immunohistochemical analysis of 23 cases

AIMS

To morphologically and immunophenotypically characterize dedifferentiated uterine leiomyosarcoma (LMS).

METHODS AND RESULTS

We identified 23 dedifferentiated uterine LMS, defined as a malignant uterine smooth muscle tumour containing discrete differentiated and dedifferentiated components (i.e. with and without morphologic and immunophenotypic evidence of smooth muscle differentiation, respectively). The differentiated component was leiomyosarcoma in most cases (17/23), though some arose from a leiomyoma (n = 4) or smooth muscle tumour of uncertain malignant potential (n = 2). The dedifferentiated tumour component showed noncohesive polygonal cells with moderate to abundant cytoplasm, pleomorphic nuclei with coarse vesicular to smudged chromatin, one or more macronucleoli, frequent multinucleation, and atypical mitoses. Three cases showed heterologous osteosarcomatous or chondrosarcomatous differentiation. Immunohistochemistry revealed alterations characteristic of uterine LMS, including Rb loss (18/19); strong diffuse p16 (17/19); strong diffuse (9/19) or complete absence of (5/19) p53; and ATRX loss (6/16). Compared to a control cohort of uterine LMS without dedifferentiation, dedifferentiated uterine LMS showed significantly shorter disease-specific (median, 54 versus 20 months; 5-year DSS, 46% versus 36%; P = 0.04) and disease-free (median, 31 versus 8 months; 5-year DFS, 42% versus 8%; P = 0.002) survival. Of 19 dedifferentiated uterine LMS with follow-up, 12 had died of disease at median 14 (range, 2-73) months; four were alive with disease at 4, 12, 44, and 50 months; and three were alive with no evidence of disease at 56, 109, and 114 months.

CONCLUSION

Routine prospective recognition of dedifferentiated uterine LMS and distinction from mimics is advocated for accurate prognostication and for further characterisation of these tumours.

"Malignant Mesenchymoma" Revisited: A Clinicopathologic Study of Leiomyosarcomas With Osteosarcomatous Differentiation

Leiomyosarcoma (LMS) is the most common sarcoma in adults. Rarely, LMS dedifferentiates into an undifferentiated sarcoma. Very few cases of LMS with heterologous osteosarcomatous differentiation (OS) have been reported. The purpose of this study was to evaluate the clinicopathologic features of LMS with OS. Of 5570 LMS cases diagnosed from 2006 to 2022, 15 cases (0.2%) of LMS with OS were identified, affecting 13 females and 2 males; ages ranged from 32 to 66 years (median: 53 y). Ten tumors arose in the uterus, 2 in the retroperitoneum, and 1 each in the mesentery, mediastinum, and rectum. Primary tumors ranged from 7 to 20 cm (mean: 16 cm). The LMS components showed conventional spindle cell morphology in most cases; 3 cases showed marked pleomorphism; 3 cases contained an epithelioid component; and 1 case showed myxoid features. In 5 cases OS was identified in the primary tumor, whereas in 10 cases OS was first detected in metastases. One metastatic and 2 primary LMS showed both OS and chondrosarcomatous differentiation. Prominent osteoclastic giant cells were seen in the OS components in 11 cases. Mitotic activity ranged from 17 to 61/10 HPF with tumor necrosis in 10 cases. Twelve patients developed metastases; sites included lungs, diaphragm, kidney, adrenal glands, colon, small intestine, liver, bone, and pancreas. At last follow-up, 8 patients had died of disease, and 4 patients were alive with metastases. The interval between OS and death ranged from 3 weeks to 18 months (median: 6.5 mo). Development of OS in LMS is exceptionally rare. This form of heterologous differentiation may occur in both primary tumors and metastases. LMS with OS is highly aggressive with poor outcomes. Awareness of this phenomenon is important to avoid misdiagnosis as osteosarcoma.

Dedifferentiated Leiomyosarcoma of the Auricle with Heterologous Osteosarcoma Component: Case Report and Literature Review

Leiomyosarcomas are rare malignant tumors of smooth muscles. Head and neck involvement by this disease is very rare, and cutaneous leiomoysarcomas of the ear are even rarer. This is way clinically they are usually mistaken for either squamous or basal cell carcinomas, as was the case in an 85-year-old male patient presented in this report. However, the final diagnosis was even more interesting considering that it was a dedifferentiated leiomyosarcoma of the auricle with a heterologous component of osteosarcoma. The auricular cutaneous malignancies have a much higher rate of recurrence than the corresponding malignancy in other regions of the head and neck, even when resected with negative surgical margins, and dedifferentiated leiomyosarcoma is clinically even more aggressive. Thus, the treatment of choice is a total auriculectomy and great attention should be paid to appropriate margins.

High grade sarcoma with chondrosarcomatous differentiation in primary uterine leiomyosarcoma; A rare case and review of literature

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Leiomyosarcoma is a malignant mesenchymal tumor of smooth muscle origin with variable morphology.

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Chondrosarcomatous differentiation in primary uterine leiomyosarcoma is quite uncommon.

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Carcinosarcoma, a malignant biphasic tumor, is more likely to be associated with homologous or heterologous differentiation.

Primary uterine leiomyosarcoma (LMS) with chondrosarcomatous differentiation is extremely rare. We report a case of a 68-year-old, African American woman who presented with postmenopausal bleeding. Ultrasonography (USG) revealed multiple uterine fibroids. Total abdominal hysterectomy with bilateral salpingo-oophorectomy (TAH/BSO) was performed. Microscopic examination of the largest intramural nodule showed high-grade sarcoma, comprising of LMS with a focal transformation to undifferentiated sarcoma with chondrosarcomatous differentiation. Endometrium was benign excluding carcinosarcoma. Heterologous differentiation has rarely been described in metastatic or recurrent uterine LMS; however, a primary uterine LMS with chondrosarcomatous differentiation has not been reported previously.

Dedifferentiated soft tissue leiomyosarcoma with heterologous osteosarcoma component: case report and review of the literature

Background

Soft tissue dedifferentiated leiomyosarcoma with heterologous osteosarcomatous component is an extremely rare entity described in only few cases in the literature.

Case presentation

We report the case of a 65-year-old male patient who, after initial inadequate surgery of a tumor of the left forearm, developed local recurrence that was treated with neoadjuvant chemotherapy, surgery and postoperative radiation therapy. Histologically the tumor showed an abrupt separation of two different patterns. One component consisted of interlacing fascicles of spindle cells with cigar-shaped nuclei strongly positive for smooth muscle actin, desmin and H-caldesmon. The other component consisted of a high-grade pleomorphic sarcoma with osteoid and chondroid matrix production, which positive for SATB2. Thus, a final diagnosis of dedifferentiated leiomyosarcoma was rendered. Fifteen months after treatment, the patient presented further local and distant relapse with pulmonary metastases and died 23 months after the first presentation.

Discussion and conclusions

Dedifferentiated leiomyosarcoma is a highly malignant neoplasm with a poor outcome. Extensive sampling of soft tissue leiomyosarcomas is recommended to detect possible dedifferentiated areas as they represent a crucial prognostic parameter.

A case of hepatic leiomyosarcoma with osteosarcomatous differentiation (malignant mesenchymoma) in a dog

A rare spontaneous hepatic leiomyosarcoma with osteosarcomatous differentiation was observed in a female beagle dog and its morphological and immunohistochemical characteristics were examined. Upon necropsy, an endoceliac mass originating from the liver was detected, which was composed of hematoid fluid-filled cysts and white to grayish solid tissue. There were no macroscopic findings in other organ systems. Histopathologically, the hepatic mass consisted of two different mesenchymal components. One form was spindle cells arranged in interlacing fascicles immunohistochemically positive for smooth muscle actin (SMA) and smoothelin, indicating leiomyosarcomatous differentiation. The other form was composed of short spindle cells positive for S-100 and was producing various amounts of eosinophilic osteoid and trabecula-like matrices positive for osteocalcin, indicating osteosarcomatous differentiation. In addition, invasive growth in the hepatic parenchyma and cell atypia were observed. Based on these findings, the mass was diagnosed as hepatic leiomyosarcoma with osteosarcomatous differentiation (malignant mesenchymoma), which might be derived from undifferentiated mesenchymal cells.

Primary leiomyosarcoma of the atrium with heterologous differentiation

We report a case of a 47-year-old female who presented with breathlessness and palpitations for two weeks. On clinical evaluation, bilateral pedal edema was noticed. A CT pulmonary angiogram showed a mass in the left atrium causing significant obstruction to cardiovascular outflow. After extensive work-up, the mass was surgically resected. Histopathological findings from the acquired specimen revealed a high-grade leiomyosarcoma with extensive necrosis and heterologous (cartilaginous) differentiation. The early postoperative period was complicated by cardiac tamponade and the patient died on the second postoperative day due to ventricular arrhythmia, shock and multiorgan failure.

SIMILAR CASES PUBLISHED

No similar cases published.

Molecular Analysis of a Recurrent Sarcoma Identifies a Mutation in FAF1

A patient presented with a recurrent sarcoma (diagnosed as leiomyosarcoma) 12 years after the removal of an initial cancer (diagnosed as extracompartmental osteosarcoma) distally on the same limb. Following surgery, the sarcoma and unaffected muscle and bone were subjected to measurements of DNA exome sequence, RNA and protein expression, and transcription factor binding. The investigation provided corroboration of the diagnosis leiomyosarcoma, as the major upregulations in this tumor comprise muscle-specific gene products and calcium-regulating molecules (calcium is an important second messenger in smooth muscle cells). A likely culprit for the disease is the point mutation S181G in FAF1, which may cause a loss of apoptotic function consecutive to transforming DNA damage. The RNA levels of genes for drug transport and metabolism were extensively skewed in the tumor tissue as compared to muscle and bone. The results suggest that the tumor represents a recurrence of a dormant metastasis from an originally misdiagnosed neoplasm. A loss of FAF1 function could cause constitutive WNT pathway activity (consistent with the downstream inductions of IGF2BP1 and E2F1 in this cancer). While the study has informed on drug transport and drug metabolism pharmacogenetics, it has fallen short of identifying a suitable target for molecular therapy.

Metastatic leiomyosarcoma of the uterus with heterologous differentiation to malignant mesenchymoma

Heterologous differentiation in metastatic leiomyosarcomas of uterine origin is an extremely rare phenomenon. We report a remarkable case of a metastatic leiomyosarcoma from the uterus with an unusual pattern of tumor progression to malignant mesenchymoma after chemotherapy. The patient, an 80-yr-old woman with a history of metastatic leiomyosarcoma of the uterus to the lungs, presented with a large intra-abdominal mass. Histologic examination of the intraperitoneal mass demonstrated a high-grade sarcoma containing various heterologous malignant mesenchymal elements including osteosarcoma, chondrosarcoma, a liposarcoma-like area, and osteoclast-like multinucleated giant cells. Only the identification of small areas of smooth muscle differentiation revealed the true nature of the tumor as a metastatic leiomyosarcoma with aberrant sarcomatous differentiation. This unique presentation emphasizes the importance of clinicopathologic correlation in the diagnosis of tumors with unusual histology.

Dedifferentiated leiomyosarcoma: clinicopathological analysis of 18 cases

AIMS

To clinicopathologically characterize the dedifferentiated variant of leiomyosarcoma in a series of 18 cases.

METHODS AND RESULTS

Dedifferentiated leiomyosarcoma was defined as showing features of low-grade leiomyosarcoma associated with a discrete undifferentiated component lacking morphological or immunophenotypic features of myogenic differentiation. Tumours developed in 11 women and seven men, with an age range of 16-84 years (median, 64 years). Sites were retroperitoneum (eight cases), limbs (four), trunk (two) uterus (two), and paratesticular and prostate (one each). In 17 cases, dedifferentiation occurred de novo in the primary tumour. Tumour size ranged from 50 to 280 mm (median: 120 mm). Histologically, most showed discrete transition from well-differentiated smooth muscle morphology to high-grade pleomorphic morphology with no smooth muscle differentiation. Unusual features in the dedifferentiated component (epithelioid and rhabdomyoblast-like morphology) were present in three cases. Heterologous osseous or chondro-osseous elements were present in two cases. Dedifferentiated areas were negative for myogenic markers in all cases. Follow-up for 13 cases (median, 36 months) showed local recurrence in 38% (5/13). So far, three patients have died of disease (median survival, 8 months), and metastasis developed in five of 13 cases.

CONCLUSIONS

Dedifferentiated leiomyosarcoma has morphological parallels with other types of dedifferentiated sarcoma, and is clinically aggressive.