Malignant gastrointestinal leiomyosarcoma and gastrointestinal stromal tumor with prominent osteoclast-like giant cells

Gastric Leiomyosarcoma in Post-Gastrointestinal Stromal Tumor Era: Revisit

Primary gastric leiomyosarcoma is an exceptionally rare disease. This review covers 41 post-gastrointestinal stromal tumor (GIST) era gastric leiomyosarcoma cases that are supported by immunohistochemistry markers. Other spindle cell lesions are also excluded through histological and immunohistochemistry evaluations. The patients range from 3 to 82 years old, with an average age of 54.6 years. The male-to-female ratio is 1.4:1, from diverse geographic areas. Patients may experience abdominal symptoms, and tumor sizes vary between 1 cm and 22 cm. Morphologically, tumors originate from the muscularis propria or the muscularis mucosae, well-circumscribed with spindle cells arranged in fascicule. Tumoral cells exhibit positivity for smooth muscle markers while being negative for GIST markers and others. The mitotic index ranges from 2 to 500/50 high power field. Ki-67 index varies from 15% to 70%. Management typically involves gastrectomy and other appropriate treatments, with tumor recurrence being uncommon. 56% of patients are alive, with 5 patients dying from this disease. Statistical analyses conducted on post-GIST era cases reveal that a mitotic index of ≥100/50 high power field, tumor recurrence, metastasis, or positive lymph nodes significantly correlate with prognosis.

Giant cell tumor of soft tissue of the colon: a case report and review of the literature

Background

A giant cell tumor (GCT) is a benign neoplasm characterized by mixture of mononuclear cells and multinucleated cells. A GCT of soft tissue (GCT-ST) is developed in various extraosseous sites, but GCT-ST of the gastrointestinal tract is very rare. GCT-ST usually has a benign course, but rare cases reported malignant potential of the tumor. Therefore, complete resection is required to prevent local recurrence or distant metastasis.

Case presentation

A 53-year-old woman was admitted for follow-up colonoscopy who underwent the colorectal endoscopic submucosal dissection (ESD) of a laterally spreading tumor at the hepatic flexure 6 months ago. A colonoscopy showed a polypoid mass about 3.5 × 2.5 cm at the previous ESD site. As endoscopic finding showed a smooth multi-nodular tumor without submucosal invasion, we performed endoscopic mucosal resection. Based on pathological and immunohistochemical findings, the lesion was diagnosed as a GCT-ST in the colon. Follow-up colonoscopy performed 6 months later revealed no evidence of recurrence.

Conclusion

This is the first report of a GCT-ST identified in the colon. Although GCT-ST generally has a benign clinical course, complete resection should be performed to prevent local recurrence and metastasis.

Two cases of primary leiomyosarcoma of sigmoid colon treated with laparoscopic surgery: A case report and a review of literature

INTRODUCTION AND IMPORTANCE

Leiomyosarcoma (LMS) of the colon is an extremely rare and highly invasive tumor arising from the muscularis propria of the gastrointestinal tract. After the introduction of oncogenic role of KIT by immunohistochemistry (IHC), the reported cases of gastrointestinal leiomyosarcoma were highly limited. True LMS of the colon is such a rare disorder that there isn't much description of its nature.

CASE PRESENTATION

We reported two very rare cases of primary leiomyosarcoma of sigmoid colon, which referred to our institution with symptoms of abdominal pain, lower GI bleeding and fatigue. After the initial investigations, both patients were diagnosed with primary LMS of sigmoid colon that underwent laparoscopic tumor resection.

CLINICAL DISCUSSION

The classical colonic LMS presents with a vast majority of non-specific symptoms including mild abdominal pain, fresh/obscure rectal bleeding, and weight loss. The most common location for colonic LMS is the sigmoid colon, and ascending colon. The prognostic factors for the disease outcome have not been established properly; however, patient age, tumor size/grade, and local/distant dissemination are of great importance.

CONCLUSION

Herein, we reported two rare cases of primary leiomyosarcoma of sigmoid colon that was treated with laparoscopic surgery.

Laparoscopic and endoscopic cooperative surgery for leiomyosarcoma of the stomach: a case report with a review of the literature

Background

Leiomyosarcoma is a rare tumor that could originate from the gastrointestinal tract, uterus, kidney, retroperitoneum, and the soft tissues of the extremities. It accounts for only 1% of all gastrointestinal mesenchymal tumors and primary leiomyosarcoma of the stomach is extremely rare. Most cases reported as leiomyosarcoma of the stomach before the development of KIT immunohistochemistry might be gastrointestinal stromal tumors (GISTs) of the stomach and only 18 cases of leiomyosarcoma of the stomach have been reported since early 2000s. We report here a patient with leiomyosarcoma of the stomach treated by laparoscopic and endoscopic cooperative surgery (LECS).

Case presentation

A 59-year-old man was referred to our hospital for an early gastric cancer, which was initially treated by endoscopic submucosal dissection. Six months after his initial treatment, a follow-up esophagogastroduodenoscopy revealed a small polypoid lesion at the lesser curvature of the proximal stomach, which appeared to be a hyperplastic polyp. However, one and a half years later, the lesion grew and showed more irregular surface. Biopsy at the time revealed smooth muscle cell proliferation suggestive of leiomyoma. Three years later, the lesion grew even larger and biopsy showed pleomorphic spindle cells. Immunohistochemical study showed positive staining for alpha-smooth muscle actin and desmin, but negative for c-kit and CD34. Ki-67 labeling index was nearly 60%. Based on these findings, the diagnosis of leiomyosarcoma was established. The patient subsequently underwent a partial gastrectomy by LECS. The patient is currently in good condition without recurrence or metastasis at 12 months after surgery.

Conclusions

Leiomyosarcoma of the stomach is extremely rare. This is the first report of leiomyosarcoma of the stomach treated by LECS. We could also follow its appearance change through endoscopic examination for 3 years.

Leiomyosarcoma of the rectosigmoid junction, a case report

Leiomyosarcomas are a rare type of neoplasm of the digestive tract with an estimated presentation of 0.1% predominantly between the fifth and sixth decade of life [1]. We report the case of a 61 years old male patient without previous medical conditions, with melena and constitutional symptoms and an extensive rectal mass with a final diagnosis of diagnosis leiomyosarcoma of the large intestine, grade II (FNCLCC). Given the rarity of this pathology and the fact that it does not present specific clinical, endoscopic, and imaging features made it difficult to differentiate from other entities of greater frequency such as rectal adenocarcinoma and GIST, representing a real diagnostic challenge.

A pooled analysis of risk factors of surgically treated leiomyosarcoma of the colon in adults

Background

This current systematic review aimed to evaluate the role of surgical management and risk factors by pooled cases from all identified patients with colonic leiomyosarcomas.

Methods

The authors searched the Ovid MEDLINE, Embase, PubMed, and Cochrane databases using the keywords “colonic,” “colon,” and “leiomyosarcoma.” Risk factors of colonic leiomyosarcoma in the pooled cohort were also evaluated.

Results

Between 1923 and 2019, 41 cases of colonic leiomyosarcoma were identified in 22 (53.7%) males and 19 (46.3%) females, with a mean and median age of 58.7 ± 2.2 years and 56.0 years. According to univariate analysis, smaller tumor size < 8 cm was significantly associated with longer progression-free survival (HR = 6.957, 95% CI 1.405–34.442; p = 0.017), and younger age < 60 years was trending toward better overall survival (HR = 2.765, 95% CI 0.924–8.272; p = 0.069).

Conclusions

Colonic leiomyosarcomas are rare neoplasms with aggressive clinical behaviors. Age < 60 years and tumor size < 8 cm were favorable factors for patients’ better survival.

Osteoclastic giant cell tumor of the pancreas with synchronous jejunal gastrointestinal stromal tumor: A case report

Osteoclastic giant cell tumor of the pancreas is a rare aggressive tumor, counting for 2–7% of all pancreatic cancers. Surgery is considered the most appropriate treatment. We report a case of a 84-year-old man with incidentally detected 11cm tumor in the pancreatic tail and another 6 cm tumor located in the jejunum on abdominal computed tomography. The patient underwent distal pancreatectomy with splenectomy along with segmental resection of the tumor bearing part of the jejunum. On histological examination, osteoclast-like giant cells with some areas of metaplastic bone were observed which confirmed the diagnosis of osteoclastic tumor of the pancreas. The jejunal tumor was strongly c-kit positive on immunohistochemistry which confirmed the diagnosis of GIST. On the last follow up at 2 years after surgery, there is no evidence of recurrence or distant metastasis. Pancreatic OGCT has a better prognosis after resection than pancreatic adenocarcinoma. Its co-existence jejunal GIST, as seen in the index case, has not been reported in the English literature till date.

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Osteoclastic giant cell tumor of the pancreas is a rare aggressive tumor, counting 2–7% of all pancreatic cancers.

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Surgery is considered the most appropriate treatment.

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Pancreatic OGCT has a better prognosis, after resection than pancreatic adenocarcinoma.

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Its co-existence jejunal GIST, as seen in the index case, has not been reported in the English literature till date.

Urinary bladder leiomyosarcoma with osteoclast-like multinucleated giant cells: a case report

Background

Bladder leiomyosarcoma is the most frequent mesenchymal neoplasm of the bladder. However, the rarity of the disease and some morphological aspects could give serious problems to differential diagnosis.

Case presentation

A 86-year-old male patient was referred to our institution to undergo endoscopic low-urinary-tract re-evaluation 2 months after the detection of a “low-grade urothelial neoplasia” in urinary cytology. A TURBT (transurethral resection of bladder tumor) was performed and revealed a tumor extending for 3.5 cm with thin stalk peduncle on the left lateral wall of the bladder, cephalad and lateral to the left ureteral orifice. The exophytic part of the tumor was resected with the underlying bladder wall. Histologically, the tumor showed a quite complex pattern, composed of spindle cells, with often invasion to the surrounding bladder muscular wall, and the presence of numerous multinucleated, osteoclast-like giant cells, scattered throughout the neoplasia.

Conclusions

Here we report a unique case of urinary bladder leiomyosarcoma with osteoclast-like multinucleated giant cells (OGCs). These cells, confounding the morphological aspect, indeed showed an immunohistochemical phenotype of non-neoplastic origin (most likely a histiocyte/macrophage differentiation). We feel that the presence of the OGCs within this tumor is reactive. Nevertheless, more research is necessary to understand the role of OGCs in urinary bladder tumors and leiomyosarcoma, in paticular.

Laparoscopic surgery to treat leiomyosarcomas of the sigmoid colon:a case report and literature review

Background

Leiomyosarcomas (LMSs) of the colon are extremely rare and highly aggressive. Although treatment of gastrointestinal LMS is not standardized, surgical resection is generally performed. The fact that the tumors are usually large at the time of diagnosis may explain why no report on laparoscopic resection of a colonic LMS has appeared.

Case presentation

A 46-year-old male presented with hematochezia 1 month in duration. Abdominal examination including palpation was normal. The levels of several blood tumor markers were normal. Colonoscopy revealed a polypoid lesion approximately 30 mm in diameter in the sigmoid colon 30 cm from the anal verge. Contrast-enhanced computed tomography revealed that the tumor was 28 mm in diameter, and that no lymph node or distant metastasis was apparent. Histopathological examination of a biopsy specimen revealed spindle-shaped cells exhibiting significant nuclear atypia and a trabecular proliferation pattern upon hematoxylin-eosin staining. Immunohistochemically, the sample was positive for SMA and desmin, and negative for c-kit, DOG-1, CD34, and S-100. Furthermore, the Ki-67 index was > 50%. We thus diagnosed a leiomyosarcoma of the sigmoid colon without any metastasis. We performed laparoscopic sigmoid colectomy and regional lymphadenectomy using five trocars. After complete curative resection, a colorectal end-to-end anastomosis was created employing the double-stapling technique. All surgical margins were negative, and no lymph node metastasis was observed. The postoperative course was uneventful, and the patient was discharged 9 days after operation. No recurrence was noted to 1 year after surgery.

Conclusions

We report the first case of a colonic LMS treated via laparoscopic surgery. Although further work is necessary to assess prognosis and to develop the treatment further, laparoscopic surgery to treat small colonic LMSs may be feasible, being both minimally invasive and curative.

Leiomyosarcoma of the stomach treated by endoscopic submucosal dissection

There have been no reports of primary leiomyosarcoma of the stomach treated by endoscopic submucosal dissection (ESD). We report an extremely rare case of gastric leiomyosarcoma that was successfully treated by ESD. An asymptomatic 74-year-old female underwent esophagogastroduodenoscopy for screening in December 2013. A centrally depressed submucosal tumor 10 mm in diameter was detected at the posterior wall of the upper gastric body. Follow-up esophagogastroduodenoscopy conducted 5 months later showed that the tumor diameter had increased to 15 mm. Endoscopic ultrasound revealed a hypoechoic mass located in the second to the middle of the third layer. Endoscopic ultrasound-guided fine-needle aspiration demonstrated a myogenic tumor. The tumor was completely resected by ESD without complications. Immunohistopathological diagnosis of the resected specimen was gastric leiomyosarcoma derived from the muscularis mucosae, with negative lateral and vertical margins. No local recurrence or metastasis has been detected at 36 months after ESD. This is the first report of gastric leiomyosarcoma treated by ESD in the English language literature.

[A case of gastric leiomyosarcoma with multiple metastases]

Leiomyosarcoma is an uncommon tumor that originates from various organs, including uterus, kidney, retroperitoneum, and soft tissues. In particular, leiomyosarcoma of the stomach is extremely rare. Only 9 cases have been reported worldwide since the discovery of KIT-activating mutation. A 48-year-old woman was admitted to our hospital with abdominal discomfort and generalized weakness. Upon detection of multiple nodules in both lung on chest posterior-anterior radiograph taken at the time of admission, chest CT was performed and it revealed multiple mass lesions in the lung, liver, and pancreas along with multiple lymph node metastases. On endoscopic examination, a 2.0 cm sized ulcerofungating mass lesion was found on the stomach body. Biopsy was performed and the mass lesion proved to be leiomyosarcoma confirmed by immunohistochemical staining. Chemotherapy was thus initiated, but the patient died after one year due to tumor progression. Our experience suggests that leiomyosarcoma can manifest aggressive behavior in its early stage. Herein, we report a case of gastric leiomyosarcoma with multiple metastases along with review of relevant literature.

Gastric carcinosarcoma with rhabdomyosarcomatous differentiation: a case report and review

We report an unusual case of gastric carcinosarcoma with rhabdomyosarcomatous and neudoendocrinal differentiation in a 71-year-old Japanese female. Gastric carcinosarcoma with rhabdomyosarcomatous and neuroendocrinal differentiation is a rare tumor. The tumor developed in the body of the stomach and was exophytic in appearance. By histochemical analysis, the tumor was shown a part of positive for desmin and myoglobin and a part of positive for synaphtophysin and vimentin.We conclude that, though rare, gastric carcinosarcoma with rhabdomyosarcomatous and neuroendocrinal differentiation thus is reviewed in the English literatures.

Gastrointestinal (GI) leiomyosarcoma (LMS) case series and review on diagnosis, management, and prognosis

This review of 76 gastrointestinal (GI) leiomyosarcoma (LMS) cases that include 11 cases from the American University of Beirut Medical Center represents, to our knowledge, the largest number of combined GI LMS cases reported. The age range of GI LMS is variable, and the presentation is non-specific, making pathological diagnosis essential. LMSs usually lack CD117 and CD 34 mutations and are usually positive for smooth muscle cell markers. The review highlights surgery as the mainstay of treatment with negative margins attained most of the times. Adjuvant chemotherapy is used in around 7-27 % of the cases mainly for small intestinal and colorectal LMS. The relatively small number of patients is a limitation on outcome analysis. However, LMS has a risk of recurrence reaching 39-80 % and secondary metastasis reaching 55-71 % in small intestinal and colorectal cases. In light of the high frequency of recurrence and metastasis, enrolling patients in clinical randomized trials to investigate the role of chemotherapy, radiation therapy, and targeted therapy is required for better control of this rare aggressive GI tumor.

Meningeal Solitary Fibrous Tumors with Delayed Extracranial Metastasis

BACKGROUND

The term solitary fibrous tumor (SFT) is preferred over meningeal hemangiopericytoma (HPC), because NAB2-STAT6 gene fusion has been observed in both intracranial and extracranial HPCs. HPCs are now considered cellular variants of SFTs.

METHODS

This study analyzes 19 patients with STAT6-confirmed SFTs, who were followed for over 11 years in a single institution. Ten patients (10/19, 56.2%) had extracranial metastases (metastatic group), while the remainder (9/19) did not (non-metastatic group). These two groups were compared clinicopathologically.

RESULTS

In the metastatic group, the primary metastatic sites were the lungs (n = 6), bone (n = 4), and liver (n = 3). There was a mean lag time of 14.2 years between the diagnosis of the initial meningeal tumor to that of systemic metastasis. The median age at initial tumor onset was 37.1 years in the metastatic group and 52.5 in the non-metastatic group. The 10-year survival rates of the metastatic- and non-metastatic groups were 100% and 33%, respectively. The significant prognostic factors for poor outcomes on univariate analysis included advanced age (≥45 years) and large initial tumor size (≥5 cm). In contrast, the patients with higher tumor grade, high mitotic rate (≥5/10 high-power fields), high Ki-67 index (≥5%), and the presence of necrosis or CD34 positivity showed tendency of poor prognosis but these parameters were not statistically significant poor prognostic markers.

CONCLUSIONS

Among patients with SFTs, younger patients (<45 years) experienced longer survival times and paradoxically had more frequent extracranial metastases after long latent periods than did older patients. Therefore, young patients with SFTs require careful surveillance and follow-up for early detection of systemic metastases.

A Review of the Literature on Primary Leiomyosarcoma of the Prostate Gland

Primary leiomyosarcoma of the prostate (PLSOP) is rare, with less than 200 cases reported so far. PLSOPs present with lower urinary tract symptoms, haematuria, and perineal pain; may or may not be associated with a history of previous treatment for adenocarcinoma of prostate by means of radiotherapy and or hormonal treatment; may afflict children and adult male. Examination may reveal benign enlarged prostate and hard enlarged mass. PLSOPs may be diagnosed by histological examination findings of spindle-shaped carcinoma cells in prostate specimens. Immunohistochemical staining tends to be positive for vimentin, CD44, smooth muscle actin, and calponin, focally positive for desmin, and at times positive for keratin. They stain negatively for PSA, S-100, CD34, CD117, and cytokeratin. Cytogenetic study on primary leiomyosarcoma of the prostate gland may show clonal chromosomal rearrangement involving Chromosomes 2, 3, 9, 11, and 19. On the whole the prognosis is poor. Surgery with or without chemotherapy would appear to be the mainstay of treatment for PLSOPs that are operable, but generally there is no consensus opinion on the best therapeutic approach. Most cases of PLSOPs are diagnosed in an advanced stage of the disease. A global multicenter trial is required to find therapies that would improve the prognosis.

Clinicopathological features of primary leiomyosarcoma of the gastrointestinal tract following recognition of gastrointestinal stromal tumours

AIMS

We aimed to elucidate the clinicopathological and immunohistochemical features of leiomyosarcoma (LMS) of the gastrointestinal (GI) tract.

METHODS AND RESULTS

We encountered seven cases of GI-LMS in the colon (n = 4), rectum (n = 1), jejunum (n = 1) and stomach (n = 1). They ranged from 1 to 25 cm (median, 8.5 cm) in size and had high mitotic counts (median 38 per 50 high-power fields). Morphologically, the tumours were composed mainly of spindle cells with eosinophilic cytoplasm and various degrees of nuclear atypia and pleomorphism. Immunohistochemically, the tumours were positive for α-smooth muscle actin (86%), muscle-specific actin (71%), desmin (86%), calponin (71%), h-caldesmon (57%) and smoothelin (71%). All were negative for KIT, CD34, protein kinase C theta and DOG1. Local recurrence and distant metastasis occurred in one and three patients, respectively. We then reviewed 55 cases of GI-LMS from the era following the recognition of gastrointestinal stromal tumours. Among 29 of 55 cases for whom follow-up information was available, the estimated 5-year overall survival rate was 51.6%; tumour size ≥5 cm was correlated significantly with shorter overall survival time (P = 0.0016), while mitotic count (≥50 or ≥100 per 50 high-power fields) proved to be no prognostic factor.

CONCLUSIONS

GI-LMSs have distinctive clinicopathological and immunohistochemical features and exhibit aggressive biological behaviour.

Gastrointestinal stromal tumor of the ampulla of Vater with osteoclastic giant cells, osteoid-like matrix deposition, and aneurysmal bone cyst-like features

Gastrointestinal stromal tumors are a heterogeneous group with a wide spectrum of histologic features. We describe the first case of 61-year-old woman who presented gastrointestinal stromal tumors of the ampulla of Vater with osteoclast-like giant cells surrounding osteoid-like material and aneurismal bone cyst-like areas. The phenotype was supported by light microscopy and corroborated by immunohistochemistry analysis. Because of the presence of osteoid-like and aneurismal bone cyst-like components, it is first necessary to make differential diagnosis with other entities such as metastatic osteosarcoma. Our case shows another form of differentiation that has not previously been reported.

Primary leiomyosarcomas of the gastrointestinal tract in the post-gastrointestinal stromal tumor era

Most mesenchymal neoplasms of the gastrointestinal tract are currently classified as gastrointestinal stromal tumors (GIST). Gastrointestinal stromal tumors are diagnosed by immunopositivity for CD117, CD34, and DOG1.1, with or without molecular analyses. According to the World Health Organization classification, the diagnosis of primary leiomyosarcomas of the gastrointestinal tract is so rare that there are no significant data on demographic, clinical, or gross features of this tumor. A comprehensive literature search was performed to identify gastrointestinal leiomyosarcomas. Searches were limited to the past 12 years because definitive tools to differentiate leiomyosarcomas from GIST were introduced in the late 1990s. Cases were included only if convincing data were presented. Six cases of esophageal leiomyosarcoma and 5 cases of gastric leiomyosarcoma were confirmed. Furthermore, 26 cases of leiomyosarcoma of the small bowel, 11 cases of the colon, and 8 cases arising in the rectum were identified. Finally, 28 cases of infantile and adolescent leiomyosarcoma were reviewed. Although survival analysis is precluded by small case numbers and limited survival data availability, the trend identifies that increased size and mitotic activity portends to a worse prognosis in small bowel leiomyosarcomas. Colonic leiomyosarcomas appear to be aggressive tumors, regardless of tumor size and mitotic activity. Rectal leiomyosarcomas present as smaller tumors with favorable prognosis. Leiomyosarcomas in post-GIST era are rare tumors of the gastrointestinal tract with distinctive clinicopathologic characteristics. Owing to different treatment options, it is necessary to accurately differentiate these from GIST, using a combination of histologic appearance, presence of smooth muscle antigens, and absence of specific GIST immunomarkers.

Gastric carcinoma with osteoblastic differentiation

INTRODUCTION

Carcinosarcoma is a rare malignant biphasic tumor which has sarcomatous and carcinomatous components. Stomach localization is very rare. We discuss the diagnosis, follow-up and treatment of patients diagnosed with gastric carcinosarcoma in company with the literature review.

PRESENTATION OF CASE

A 73-year-old white male patient applied to hospital with dyspeptic complaints lasting for 2months. His endoscopic examination revealed an ulcero-vegetating mass in the cardiac region of his stomach. Total gastrectomy and D2 lymph node dissection were performed for the patient. In the pathologic evaluation, the tumor was found consistent with Stage IIA stomach adenocarcinoma in accordance with AJCC (7edt, 2010) classification. Pathologic specimen was reevaluated by an expert pathologist for the patient with progression and liver metastasis under adjuvant chemotherapy and concomitant radiotherapy. The new pathology was consistent with gastric carcinosarcoma, and 90% of the tumor was identified as osteosarcoma whereas 10% was identified as carcinoma. Cisplatin doxorubicine-based chemotherapy was given considering the fact that sarcomatous component was dominant.(1) The patient was given 3 courses of chemotherapy. However, as the patient showed progression under therapy, he died after 14months of the diagnosis.

DISCUSSION

Gastric carcinosarcoma is a very rare and clinically aggressive malignancy. Recurrence is likely to occur with a rate of more than 50% in patients who have undergone resection within the first year following surgery, and overall survival time is 10-15months.

CONCLUSION

In refractory gastric carcinoma cases with rapid progression, we suggest that gastric carcinosarcoma with biphasic component should be taken into consideration and the pathological evaluation should be performed by an expert pathologist.

Incidental detection of gastrointestinal stromal tumor by Tc-99m MDP bone scan

This case demonstrates extraosseous 99m-technetium methylene diphosphonate (Tc-99m MDP) accumulation from a gastrointestinal stromal tumor. A 75-year-old woman underwent a temporal bone CT for conductive hearing loss that showed sclerosis in the right occipital condyle. Follow-up Tc-99m MDP bone scan for osseous metastases instead showed a mass-like extraosseous accumulation of Tc-99m MDP in the anterior left upper quadrant. Differential diagnoses included gastric cancer, lymphoma, metastatic melanoma, systemic hypercalcemia, or heterotopic mesenteric ossification. Contrast CT showed a well-circumscribed mass arising from the stomach, and subsequent pathology confirmed gastrointestinal stromal tumor. These tumors rarely can contain osteoclast-like giant cells and should be considered for extraosseous Tc-99m MDP accumulation.

Coexistence of primary gastric giant cell-rich leiomyosarcoma and gastrointestinal stromal tumor: report of a very rare combination and review of the literature

Leiomyosarcoma is one of the most common types of soft tissue sarcoma, usually seen in deep soft tissues of the extremities and retroperitoneum. Leiomyosarcoma primarily involving the gastrointestinal tract is uncommon. This report presents a rare case of primary gastric giant cell-rich leiomyosarcoma associated with a gastrointestinal stromal tumor of the stomach in a 51-year-old man. The patient was alive with no evidence of recurrence 10 months later. To the authors' knowledge, this association has not been previously reported.

Giant cell tumor-like lesion of the urinary bladder: a report of two cases and literature review; giant cell tumor or undifferentiated carcinoma?

Summary

Giant cell tumor, excluding its prototype in bone, is usually a benign but local aggressive neoplasm originating from tendon sheath or soft tissue. Malignant behavior is uncommon. Visceral organ involvement including urinary bladder is rare. Giant cell tumors in visceral organs usually accompany epithelial tumors and the clinical behavior of giant cell tumor in urinary bladder is similar to its bone counterpart. Here, we report two cases of giant cell tumor located in urinary bladder in comparison with nine reported cases in the English literature. Concurrent noninvasive urothelial carcinoma was also described in all these previous reports and only one patient with follow-up died of disease. One of the two cases we present had no concurrent urothelial tumor at the time of diagnosis but had a history of a low grade noninvasive urothelial carcinoma with three recurrences. The histology of these two cases was similar to the giant cell tumor of bone and composed of oval to spindle mononuclear cells with evenly spaced osteoclast-like giant cells. Immunohistochemically, the giant cells showed staining with osteoclastic markers including CD68, TRAP, and LCA. Immunohistochemical expression of vimentin, CD68, LCA, and smooth muscle actin in mononuclear cells supported a mesenchymal origin with histiocytic lineage. The histologic and immunohistochemical properties in our cases as well as their clinical courses were consistent with a giant cell tumor. Consequently, tumors in urinary bladder showing features of giant cell tumor of bone may also be considered and termed "giant cell tumor".

An Atypical Equine Gastrointestinal Stromal Tumor

A 17-year-old, gelded Quarter Horse cross was found to have a large, intra-abdominal mass. Clinical signs included infrequent mild colic, weight loss, and chronic anemia. Surgery revealed a very large, discrete, hemorrhagic, multilobular mass with vascular attachments to the transverse colon, mesocolon, jejunal mesentery, and omentum; the site of origin was the transverse colon. Histologic examination demonstrated dense sheets, fascicles, palisades, and interconnecting streams of neoplastic spindle cells with lesser numbers of admixed multinucleated giant cells. Based on morphology alone, this neoplasm might have been misdiagnosed as a peripheral nerve sheath tumor because many of the morphologic features were suggestive of neural differentiation. Neoplastic cells expressed cluster of differentiation (CD)117 (c-kit), vimentin, desmin, smooth muscle actin, neuron-specific enolase, and S-100 protein and did not express cytokeratin. Based predominantly on the immunohistochemical profile, especially the CD117 positivity, this neoplasm was diagnosed as a gastrointestinal stromal tumor with both myogenic and neurogenic differentiation. The morphology and immunohistochemical profile of this neoplasm were different from published cases of equine gastrointestinal stromal tumors. Unusual aspects included the large size of this neoplasm, the neuroid rather than myxomatous morphology, the presence of multinucleated giant cells, and the expression of desmin.

Primary leiomyosarcoma of the nipple-areola complex: report of a case and review of literature

Primary leiomyosarcoma of the nipple-areola complex is extremely rare. Less than ten such cases have been reported in English literature so far. Herein we describe a 52-year-old female presenting with a 1.5 cmx1.1 cmx0.7 cm nodular lesion over her left nipple, and leiomyosarcoma was proved by pathological examination of the excised specimen. Positron emitted tomogram (PET) revealed no abnormal signal other than the primary site. Microscopically, this poorly circumscribed tumor was composed of interlacing bundles of smooth muscle cells with bizarre and pleomorphic nuclei, as well as prominent nucleoli. Its mitotic count was up to 7 mitoses per 10 high power fields (HPF). Immunohistochemical study of tumor cells revealed positive stain for alpha-smooth muscle actin and vimentin; and negative for cytokeratin, CD34 and S-100. Left simple mastectomy was undertaken and no residual mass lesion was noted on the resected specimen. Related literatures about the diagnosis and treatment for breast leiomyosarcoma will be presented here.

Carcinosarcoma of the stomach: A case report and review of the literature

Carcinosarcomas are rare, malignant, biphasic tumors. We report the case of a 62-year-old man with gastric carcinosarcoma, along with its clinical, macroscopic and histopathological features. Macroscopically, a specimen of deformed stomach was obtained that measured 200 mm × 150 mm × 100 mm. A 150 mm × 100 mm × 50 mm exophytic tumoral mass (Borrmann typeI) was found, which involved the posterior wall from the cardia to the antrum. Histopathologically, a mixed type of malignancy was revealed: an adenocarcinoma with intestinal metaplasia, with interposed fascicles of fusiform atypical cells and numerous large, rounded and oval cells. The tumor showed positive histochemistry for cytokeratin 18, epithelial membrane antigen, carcinoembryonic antigen, chromogranin A and vimentin. Liver metastases were diagnosed 8 mo postoperatively, and the patient died 4 mo later. A review of the available literature is also presented.

[Malignant phyllodes tumor of the breast with osteoclast-like giant cells: a case report]

Breast tumors, particularly of stromal origin, containing multinucleated osteoclast-like giant cells (OLGC) are rarely reported in the literature. We report here the first case of a malignant phyllodes tumor associated with OLGC occurring in a 43 year-old African woman who presented with a painful palpable mass of the outer upper quadrant of the right breast. After surgical excision, histological examination showed a malignant phyllodes tumor in which the stromal component displayed evident sarcomatous changes and was densely populated with benign multinucleated OLGC. These cells expressed the CD68 histiocytic marker. No evidence of osseous or cartilaginous differentiation was seen throughout the lesion. This lesion ressembles giant cell tumor of bone. However, the nature of the OLGC is not well precised yet.

Primary and metastatic high-grade pleomorphic sarcoma/malignant fibrous histiocytoma of the gastrointestinal tract: an approach to the differential diagnosis in a series of five cases with emphasis on myofibroblastic differentiation

Primary and metastatic so-called malignant fibrous histiocytoma/undifferentiated high-grade pleomorphic sarcoma (MFH) is rare in the gastrointestinal (GI) tract with approximately 50 primary and five metastatic cases reported so far. We evaluated two primary gastric and three metastatic intestinal high-grade pleomorphic sarcomas with features of storiform-pleomorphic MFH. Gastric tumours occurred in a 79-year-old man and a 68-year-old woman. One patient died post-operatively, and the other was disease-free at 6 months. Three patients presented with GI metastasis 24, 60 and 0 months after diagnosis of MFH of the heart (n = 1) and the thigh (n = 2). Metastases were located in the small (n = 1) and large bowel (n = 2) and were characteristically pedunculated and polypoid with oedematous haemorrhagic stroma. Concurrent metastases (brain, lung, bone) were present in all three cases. Tumours expressed alpha-smooth muscle actin (four of five), platelet-derived growth factor receptor (PDGFR) alpha (three of three) and PDGFRbeta (two of three) but were negative for CD117, CD34 and other lineage-specific markers. Ultrastructural examination revealed myo/fibroblastic features. Both gastric MFH were wild type for KIT and PDGFRalpha. In conclusion, primary and metastatic MFH of the GI tract commonly express PDGFRalpha and show a myo/fibroblastic phenotype. They should be distinguished from a variety of primary and metastatic pleomorphic neoplasms, in particular high-grade sarcomatous GI stromal tumours (GIST), pleomorphic leiomyosarcoma, sarcomatoid carcinoma and other mimics.

Synchronous GIST with osteoclast-like giant cells and a well-differentiated neuroendocrine tumor in Ampula Vateri: coexistence of two extremely rare entities

Mesenchymal tumors of the gastrointestinal system with variable histopathological appearances and constant expression of CD117 are known as gastrointestinal stromal tumors (GISTs). Neuroendocrine tumors may be seen in the gastrointestinal system and other organ systems of the body. We report a 44-year-old male patient with a 6.5 x 3 x 6cm mass located in the Ampulla of Vater. Histopathologic examination revealed a GIST with a marked nuclear pleomorphism and a high mitotic rate, and that was rich in osteoclast-like giant cells (OGC). Immunohistochemically, GIST was positive for CD117, while OGCs were negative for CD117 and positive for CD68 and alpha1-antitrypsin. There was also found a well-differentiated neuroendocrine tumor near the GIST, in the serosal aspect of the duodenum at the point of the Ampulla of Vater. This second tumor was 20mm in diameter, and was relatively well circumscribed with few glands invading the GIST. This tumor was positive for synaptophysin and chromogranin. Neither mitosis nor vascular invasion was observed. The patient had no familial history or clinical manifestations of neurofibromatosis. This case presents the unique synchronous existence of two extremely rare entities, a GIST with OGC and a well-differentiated neuroendocrine tumor, both located in the Ampulla of Vater.

Gastrointestinal stromal tumors: diagnostic challenges and practical approach to differential diagnosis

Over the last decade, gastrointestinal stromal tumors (GISTs) have evolved from histogenetically obscure gastrointestinal mesenchymal tumors to well-defined tumors with distinctive clinical, morphologic, ultrastructural, histogenetic, and molecular characteristics, for which targeted therapy is available. This is largely attributable to the discovery of CD117 overexpression and activating mutations in c-kit or platelet-derived growth factor alpha genes in most of GISTs. The availability of specific diagnostic tests and targeted therapy for GISTs has led to an increased awareness of these tumors. At the same time, the list of potential GIST mimics has lengthened considerably and it has become increasingly important that GISTs be distinguished from their mimics because correct diagnosis has implications for both treatment and prognosis. The purpose of this review is to provide an update of the expanding differential diagnosis of GISTS, to draw attention to unusual GIST variants, to provide a practical approach the differential diagnosis of GISTs and to highlight some of the challenges faced by pathologists in resolving this differential diagnosis.

Multinucleated stromal giant cells in colonic lamina propria

AIMS

Multinucleated stromal giant cells occur in the anus, genitals and many other organs. They resemble myofibroblasts, react to local injury and are found incidentally or in association with various lesions. They have only rarely been reported to occur in the colon. The aim was to firmly establish their existence in colorectal lamina propria.

METHODS AND RESULTS

Specimens from one hundred biopsies taken from throughout the colon (70%) and rectum (30%) were retrospectively reviewed. Multinucleated stromal giant cells occurred in 23 specimens (23%), were pancolonic but surprisingly spared rectal mucosa (0%). Multinucleated stromal giant cells occurred in both normal mucosa and abnormal mucosa and appeared to be larger and more numerous in abnormal mucosa than in normal mucosa. Specimens with tubular adenomas appeared to have strikingly abundant multinucleated stromal giant cells with large numbers of nuclei. Immunohistochemistry and ultrastructural examination showed features consistent with myofibroblastic differentiation.

CONCLUSIONS

We have firmly established the existence of multinucleated stromal giant cells in colonic lamina propria and confirm their myofibroblastic differentiation. They may be more common in abnormal mucosa and particularly prominent in the setting of tubular adenoma. Absence of rectal multinucleated stromal giant cells may represent a microanatomical difference between the colon and rectum.

Primary oral leiomyosarcoma: a clinico-pathologic study and analysis of prognostic factors

This clinico-pathologic study of primary oral leiomyosarcomas and analysis of potential prognostic factors involved a literature review of 64 cases and a report of four cases treated in the authors' unit. The demographic details, clinical presentation, diagnosis, treatment and outcome were documented for the whole group and clinico-pathologic variables analysed to detect potential prognostic factors. The most common presentation was that of a painless mass, with peak incidence in the 6th decade and a slight male predeliction (M:F=1.3:1). The maxilla was the most frequently involved site, followed by the mandible and tongue. Surgical excision was most commonly employed with radiotherapy and chemotherapy being reserved for recurrent and metastatic tumours. Local recurrence (34%) and metastasis (35%) were not uncommon and occurred most frequently to the lungs and regional lymph nodes (15%). Age, sex, size and mitotic index were not statistically related to recurrence or metastasis. Site (P=0.0125) was a predictor of metastasis. Metastasis (P=0.010) and lesions involving the maxilla and mandible (P=0.019) were associated with decreased survival. The estimated 5 year survival was 55% for the whole group and 43% and 19% for patients with bony involvement and metastasis respectively.

Uterine leiomyosarcoma with osteoclast like giant cells and long standing systemic symptoms

INTRODUCTION

The leiomyomatous type of uterine sarcoma with osteoclast-type giant cell component is a rare variant of uterine tumors with poor prognosis. The histological diagnosis of these rare tumors can be problematic and only five such tumors have been published previously.

CASE REPORT

A 54-year-old woman presented with fever and weight loss for 7 months and laboratory findings suggestive of inflammation. After extensive clinical investigation, a uterine tumor was found, which was considered to be an incidental finding and was thought to be unlikely to explain the symptoms. After hysterectomy, the patient had a surprising and quick recovery with the complete relief of systemic symptoms and normalization of laboratory changes. The tumor was a dedifferentiated leiomyosarcoma with osteoclast-like giant cells and contained extensive necrosis. The patient continues to do well and is tumor-free 1 year after the operation.

DISCUSSION

To our knowledge, this is the first report of a patient being alive and disease-free 12 months after surgery with a dedifferentiated uterine leiomyosarcoma with osteoclast-like giant cells.

Recurrent high-grade leiomyosarcoma with heterologous osteosarcomatous differentiation

Leiomyosarcomas (LM) of the soft tissue comprise approximately 5-10% of all soft tissue sarcomas. Besides the classic LM, several distinctly uncommon features of the cellular and growth patterns of LM have been described. The term "dedifferentiated LM" has rarely been used in the literature to describe soft tissue LM containing areas of undifferentiated, pleomorphic appearance or detectable heterologous differentiation. We report on a case of high-grade LM with almost entire transition to an osteosarcoma, which was classified as recurrent high-grade LM with heterologous osteosarcomatous differentiation. The identification of areas with osteosarcomatous dedifferentiation in soft tissue sarcomas can be of clinical importance because of a possible change in oncologic treatment strategies.

Osteoclast-rich tumor of the gastrointestinal tract with features resembling those of clear cell sarcoma of soft parts

Clear cell sarcoma is a high-grade sarcoma with morphological features resembling those of malignant melanoma. An osteoclast-rich tumor of the gastrointestinal tract with features resembling those of clear cell sarcomas of soft parts is very rare. Herein, we report an unusual stomach tumor with microscopic and immunohistochemical characteristics of an osteoclast-rich tumor of the gastrointestinal tract with features resembling those of clear cell sarcomas of soft parts. The tumor cells were predominantly oval, admixed with some round and spindle elements arranged in nests and fascicles, and admixed with scattered osteoclast-like multinucleated giant cells. Neoplastic cells were positive for S-100 protein, and osteoclast-like multinucleated giant cells were immunoreactive to CD68. The unusual morphology of the tumor caused significant diagnostic difficulties. The differential diagnosis included gastrointestinal stromal tumor, primary or metastatic melanoma, and epithelioid malignant peripheral nerve sheath tumor. To the best of our knowledge, this is possibly the second description of an osteoclast-rich tumor of the gastrointestinal tract with features resembling those of clear cell sarcomas of soft parts.