Positive Staining For S-100 Protein Research Articles

Rare Hybrid Perineurioma and Granular Cell Tumor: A Pediatric Case.

We present a case of a 13-year-old patient with a distinct tumor with both granular cell and perineurial elements, located on the lower lip. The patient presented with a long-standing lip mass that was clinically felt to most likely represent a mucocele. Following surgical excision, histopathological examination revealed a well-circumscribed tumor composed of granular cells with positive S100 protein staining and spindled cells positive for EMA and GLUT-1, confirming mixed neuroectodermal and perineurial origin. This is the first case documenting a perineurial-granular cell hybrid tumor in a patient under 18 years old, and the first to be reported in the head and neck. This case expands our understanding of hybrid PNSTs, emphasizing the importance of considering diverse clinical presentations, especially in the context of rare pediatric occurrences in atypical locations.

Paediatric Clear Cell Sarcoma of Scalp Masquerading as Benign Sebaceous Cyst: A Diagnostic Dilemma

Clear Cell Sarcoma of Soft Tissue (CCSST) is a rare and aggressive tumour comprising 1% of all soft tissue sarcomas. They tend to recur locally and have a high predilection for regional, as well as, distant metastases. These tumours usually occur in a young age group; however, their presentation in childhood is extremely rare. They are also known as Malignant Melanoma (MM) of soft parts due to similar histological and Immunohistochemical (IHC) features with MM. Distinguishing between them is very difficult morphologically. Both exhibit high lymph node metastases and positive staining for S-100 protein, Melanoma antigen (Melan-A) and Human Melanoma Black-45 (HMB-45). Here, the authors reported an unusual case of an 11-year-old male child who presented with a slowly progressing scalp swelling that was misdiagnosed as a sebaceous cyst radiologically and on Fine Needle Aspiration Cytology (FNAC), which later turned out to be CCSST on histopathology. Unfortunately, the patient was lost to follow-up, but later presented with multiple cutaneous swellings, emphasising the tumour’s aggressive nature. The index case is being reported as an exception to its age of occurrence and unusual presentation that posed a diagnostic dilemma, leading to a delay in treatment. The treatment for CCSST involves wide surgical resection with negative margins, and adjuvant therapy may be considered based on resection outcomes. In conclusion, the present case underscores the diagnostic challenges posed by CCSST, particularly when it occurs in atypical age groups and locations. Timely recognition and differentiation from similar entities, such as MM, are crucial for appropriate management and improved outcomes.

Granular Cell Tumor of the Hypopharynx: A Rare Case Report

Aims: Granular cell tumor is an extremely rare tumor, accounting for 0.5% of all soft tissue tumors. This rare neoplasia have variable age, sex and ethnicity predilection. Positive staining for S-100 protein confirms the diagnosis and no harmonized treatment guideline is established. We report true this manuscript a rare case of benign of granular cell tumor of the hypopharynx. Materials and Methods: Case report. Results: We add to the literature arsenal of this entity by reporting this rare case of benign of granular cell tumor of the hypopharynx in A 74 years-old female patient with hypertension, suffered from dysphonia for about 6 months. Examination identified a budding tumor in the left piriform sinus. Ct scan showcased a 1 cm irregular, spontaneously hypodense, slightly enhanced after injection mass, infiltrating the left piriform sinus. Excisional biopsy confirmed the diagnosis and follow-up was uneventful. Conclusion: Originating from the Schwann cells; Granular cell tumor has nonspecific symptoms and usually displays as small, smooth, submucosal lesion. Variant of this tumor can be classified as either as synchronous or metachronous, or either malignant, begin or atypical.

Gastrointestinal schwannomas: a rare but important differential diagnosis of mesenchymal tumors of gastrointestinal tract

BackgroundSchwannomas of gastrointestinal tract are rare, mostly benign and notably different neoplasms from conventional schwannomas that arise in soft tissue or the central nervous system. These tumors are of clinical importance since they should always be considered in the differential diagnosis of submucosal lesions of gastrointestinal tract.MethodsSeven patients with a pathologically proven gastrointestinal schwannoma were identified in our series of mesenchymal tumors and reviewed retrospectively. Clinicopathological and immunohistochemical parameters along with the follow-up results were analysed.ResultsThe series included two males and five females, with a mean age 69 years (range, 39–81). Most patients were asymptomatic on presentation, except for two patients with abdominal pain. In the other cases (n = 5), the tumor was an incidental finding during other medical, imaging or surgical procedures. The tumors were located in the stomach (n = 4) and in the small intestine (n = 3) with an average size of 29 mm (range, 12–70). A preoperative diagnosis was achieved only in one case with a CT-guided core biopsy. Otherwise the clinical, intraoperative, endoscopic or radiological findings were unspecific. Patients with gastric tumor underwent either laparoscopic (n = 2) or open (n = 2) gastric wedge resection of the tumor; in the cases of intestinal tumor (n = 3) a segmentectomy was performed. Pathological examination revealed solid homogenous tumors, which were highly cellular and composed of spindle cells with positive staining for S100 protein, and confirmed the diagnosis of schwannoma. All tumors were negative for c-Kit, smooth muscle actin, desmin and DOG-1 and showed very low proliferation index. There were negative resection margins and no malignant variants were recognized. At an average follow-up of 60 months (range, 24–185) all patients were free of disease with no signs of recurrence or metastases and acceptable gastrointestinal function.ConclusionsSchwannomas are rare, slow-growing and mostly asymptomatic gastrointestinal mesenchymal tumors. They are difficult to be diagnosed preoperatively as endoscopic and radiological findings are nonspecific but histological and immunohistochemical features are of paramount importance to differentiate between benign and malignant schwannomas, or other spindle cell sarcomas. The treatment of choice is complete surgical excision without a conclusive preoperative diagnosis, and the long-term outcome is excellent as these lesions are mostly benign.

Pancreatic schwannoma: a case report and an updated 40-year review of the literature yielding 68 cases

BackgroundPancreatic schwannoma is a rare tumor. Preoperative diagnosis of pancreatic schwannoma is challenging due to its tendency to mimic other lesions of the pancreas. We describe a case of pancreatic schwannoma and present a review of the cases currently reported in the English literature to identify characteristics of pancreatic schwannoma on imaging.Case presentationA 53-year-old male presented with a history of intermittent periumbilical abdominal pain and lower back pain for 1 week. Based on ultrasound (US) and computed tomography (CT) findings, we made a preoperative diagnosis of solid pseudopapillary tumor and performed a standard pancreaticoduodenectomy. Pathological examination showed that the tumor was composed of spindle cells with a palisading arrangement, and immunohistochemistry revealed strong positive staining for S-100 protein, which was consistent with a diagnosis of pancreatic schwannoma. At the 8-month follow-up visit, the patient was doing well without recurrent disease, and his abdominal pain had resolved.ConclusionsAlthough pancreatic schwannoma is rare, it should be included in the list of differential diagnoses of pancreatic masses, both solid and cystic. A tumor size larger than 6.90 cm, vascular encasement, or visceral invasion should elicit suspicion of malignant transformation.

Benign esophageal schwannoma: a brief overview and our experience with this rare tumor

BackgroundBenign esophageal tumors are uncommon, comprising approximately 2% of esophageal tumors. Esophageal schwannomas constitute an even rarer entity, with few cases reported in the literature.Case presentationWe present a 66-year-old male who was referred for dysphagia. A computed tomography scan showed a well-demarcated, enhancing, and homogenous esophageal tumor measuring 50 mm. The tumor was hypermetabolic on positron emission tomography, and an endoscopic ultrasound-guided fine needle aspiration demonstrated the presence of benign spindle cells. We performed an uncomplicated, simple, tumor enucleation through a cervical approach. Histology revealed spindle-shaped cells in a fasciculated, disarrayed pattern. Immunohistochemistry demonstrated positive staining for S-100 protein and negative staining for KIT, CD34, desmin, and α-smooth muscle actin. These findings were consistent with a benign esophageal schwannoma.ConclusionsWe report our experience with esophageal schwannoma, a rare but benign diagnosis of the esophagus.

Adrenal Schwannomas: Rare Tumor of the Retroperitoneum.

Schwannoma is a benign neurogenic tumor originating from Schwann cells. These produce the myelin sheath that covers peripheral nerves that are often affected. This latter localization is extremely rare, and only a few case reports can be found in the medical literature. Studies have shown that approximately 0.5% to 5% of schwannomas are retroperitoneal, constituting 0.2% of adrenal incidental tumors. These usually present as incidental findings, nonsecreting adrenal masses in asymptomatic patients. Diagnosis of a schwannoma is based on detection of spindle cells with Antoni A and Antoni B regions in histological sections and positive staining for S-100 protein by immunohistochemical analysis. We report a case of an incidentally identified during an abdominal ultrasound examination with schwannoma localized in the left adrenal gland.

Sustained remission after ABVD treatment for interdigitating dendritic cell sarcoma.

Sustained remission after ABVD treatment for interdigitating dendritic cell sarcoma.

Multinodular Reticular Schwannoma in the Head and Neck Region

Reticular/microcystic schwannoma is a recently described morphologic variant of schwannoma that occurs predominantly in visceral organs, most commonly the gastrointestinal tract. This report describes a case occurring in the masticator space, accompanied by focal erosion of the orbital floor, clinically and radiologically worrisome for malignancy. The 26-year-old man presented with facial swelling for 3 month. The tumor shows a multinodular appearance, with dense lymphoplasmacytic infiltrates in the fibrous septa. The tumor nodules are composed of plump spindle cells disposed in a reticular pattern. The diagnosis is confirmed by strong positive staining for S100 protein. The differential diagnoses of reticular schwannoma in the soft tissues of head and neck region are different from those in the gastrointestinal tract.

Gastrointestinal: Asymptomatic colonic schwannoma in an elderly woman; a rare case

A 70-year-old woman presented following a positive fecal occult blood test. She did not have abdominal tenderness or a palpable tumor. She had no past medical history apart from hypertension and no family history of note. Her laboratory data revealed hemoglobin 12.5 g/dL, leukocyte count 5,780/mm3, CRP 0.52 mg/dL, and normal tumor marker levels. A contrast-enhanced computed tomography (CT, Figure 1) scan revealed a large, contrast-enhancing mass in her left lower abdomen. Regional lymphadenopathy was noted, but no distant metastasis was detected. Colonoscopy revealed a round, rubbery mass with an ulcerated mucosal surface in the descending colon. (Figure 2) Biopsies unfortunately provided no definite diagnosis. Contrast-enhanced CT revealed a large, solid mass, 5 cm in diameter in the descending colon. Colonoscopy revealed a large, round mass in the descending colon with a negative cushion sign. A left hemi-colectomy with regional lymphadenectomy was performed. A yellow, solid tumor with a clear margin was seen to extend to the subserosal layer (Figure 3). Microscopic and immunohistochemical examinations diagnosed the tumor as a colonic schwannoma (Antoni A and B types). Immunohistochemistry was negative for smooth muscle markers such as actin and desmin, as well as c-KIT. Positive S-100 protein staining was found (Figure 4). A hard, elastic tumor with a necrotic mucosal surface was detected on the anti-mesenteric side of the descending colon. Histology of the tumor revealed spindle-shaped cells are observed in a fascicular pattern, which was positive to S-100 protein staining and negative to c-kit staining. Colorectal schwannomas are extremely uncommon. Miettinen reported that colorectal schwannomas accounted for only 3% (20/600 cases) of all colorectal mesenchymal tumors, and only 2 such tumors were detected in the descending colon. Most schwannomas are benign but gastrointestinal tract schwannomas may occasionally undergo malignant transformation. Complete surgical resection provides the diagnosis, and in most cases, the cure. Contributed by

Erythematous Maculopapular Rash Covering Entire Body

Erythematous maculopapular rash covering entire body.Physical examination shows an erythematous maculopapular rash covering the infant’s entire body, including the face, trunk, and extremities, but no rash on the palms and soles. Lesions are in various stages of healing, with some appearing vesicular. Mucous membranes are spared. The baby is in no distress and has no other significant findings on examination.The baby undergoes a full sepsis evaluation, including lumbar puncture. Intravenous ampicillin, gentamicin, and acyclovir therapy is started. An umbilical venous line is placed due to difficulty in obtaining percutaneous venous access.The penile foreskin that was removed during circumcision contains a lesion and is sent to pathology in lieu of a skin biopsy.Erythematous maculopapular rash over entire bodyCongenital self-healing Langerhans cell histiocytosisCongenital self-healing Langerhans cell histiocytosis (CSHLCH) is a rare, usually benign, form of Langerhans cell histiocytosis. It was first reported by Hashimoto and Pritzker, who described multiple reddish-brown papulonodules in a newborn girl that showed infiltrating reticulohistiocytes on the skin biopsy and resolved without treatment within a few months. (1) The condition is now alternatively known as Hashimoto-Pritzker disease.The presentation of CSHLCH may mimic other disorders, requiring a thorough evaluation. The other conditions include neonatal hemangiomatosis, (2) congenital infections, pustular melanosis, erythema toxicum, erythropoiesis dermica, and congenital leukemia. (3)In addition to its clinical presentation of a spontaneous eruption of crusted reddish-brown nodules and papules all over the body, the diagnosis is confirmed by pathologic examination of skin containing the papular lesion. Characteristic histologic findings are positive staining for S-100 protein and membranous staining for CD1a antigen in lesional cells. Birbeck granules may also be seen by electron microscopy. Low-density microscopy may show eosinophils or multinucleated giant cells.Kapur and associates(4) published a case series from a 10-year period at Dallas Children’s Medical Center that consisted of 11 cases. All but one of the cases presented at birth; the single other case was diagnosed at 1 month of age. All of the affected infants had only skin involvement at presentation, and all were alive and without evidence of disease at follow-up evaluation.The prognosis for infants who have cutaneous CSHLCH without any other organ involvement is excellent. However, Larralde and associates(5) and others suggest an initial thorough screening evaluation. Such a screening should include a full physical examination; complete blood count; serum chemistry; liver function tests; skull, chest, and long bone radiographs; and abdominal ultrasonography. Bone marrow examination should be performed based on the degree of suspicion of progressive disease. Skin biopsy confirms the diagnosis and is helpful in diagnosing future relapses. Children who have CSHLCH require close follow-up for signs of disease progression, which underscores the importance of making an early diagnosis.JoDee M. Anderson, MD, MEd, Division of Neonatal Medicine, Oregon Health & Science University, Portland, OR.

Lovastatin Promotes Redifferentiation of Human Nucleus Pulposus Cells During Expansion in Monolayer Culture

To acquire the capacities for matrix production and preservation of an expanded volume within a damaged intervertebral disc (IVD), cells isolated from human nucleus pulposus (NP) tissues must undergo several passages in monolayer culture. However, chondrocytes and IVD cells in monolayer culture undergo "dedifferentiation," characterized by decreased synthesis of type II collagen and increased synthesis of type I collagen, thereby compromising the properties of regenerative tissues. The present study was undertaken to ascertain whether lovastatin reverses "dedifferentiation" of human NP cells during monolayer expansion. Expression of genes encoding type II collagen and transcription factor SOX9 in these cells was upregulated by lovastatin, with maximal stimulations observed at 5 µM, whereas type I collagen gene expression was suppressed by the drug, with maximal inhibitions observed at 5-10 µM. At lovastatin concentrations ≥1 µM, expression of genes encoding the bone morphogenetic proteins BMP-2 and BMP-7 was also significantly enhanced. Furthermore, the number of NP cells exhibiting a rounded shape and positive staining for S-100 protein and type II collagen protein increased during treatment with lovastatin. These findings strongly support the induction by lovastatin of "redifferentiation" of human NP cells during their expansion in monolayer culture.

Granular cell tumor of the suprasternal space

A case of granular cell tumor (GCT) was reported. We encountered a 33-year-old woman with a painless, elastic, hard mass in the soft tissue of the suprasternal space. The tumor was excised with several millimeters margin of normal tissue above the deep cervical fascia and the wound was closed primarily. Histological examination on hematoxylin-eosin stain showed a tumor growth in the mid- to deep dermis and eosinophilic small granules that were consistent with granular cell tumors. Immunohistochemical studies showed positive staining for S-100 protein. We experienced a case of a granular cell tumor occurring in the suprasternal space and report the importance of including it in the differential diagnosis of subcutaneous soft tissue tumors.

Desmoplastic Malignant Melanoma Presenting as Large Lung Mass

We describe a case of successful minimally invasive thoracoscopic surgical resection of metastatic desmoplastic malignant melanoma replacing the entire right lower lobe of the lung, presenting 4 years after the initial complete resection of the primary scalp lesion. An 89-year-old man presented with a 6-month history of right-sided chest pain. A computed tomographic scan showed a large paravertebral mass with possibility of chest wall invasion. Core biopsy initially raised the suspicion of a schwannoma. We also discussed the atypical delayed presentation and misleading radiologic and histologic findings.

S100, HMB-45, and Melan-A negative primary melanoma

The diagnosis of malignant melanoma can be challenging given the wide variation in morphologic features and immunohistochemical stains are often used to confirm the diagnosis. We report a case of melanoma with loss of staining for S100 protein, HMB-45, and Melan-A, with retained expression of tyrosinase. Regional lymph node metastases showed positive S100 protein staining. Although the loss of phenotypic markers including S100 protein has been reported in metastatic melanoma, loss of S100 in primary melanoma is rare. Discordant staining between primary and metastatic lesions further emphasizes the protean nature of melanoma.

Ancient schwannoma of oral cavity: A case report

Introduction: Ancient schwannoma is a rare variant of schwannoma that rarely occurs in the oral cavity. Histologically it can be confused with a malignant mesenchymal tumor. Therefore it is important to differentiate them from each other. Case report: The patient was a 40 – year – old male with the complaint of a painless gradual swelling in the left side of the mandibular lingual gingiva for about 5 years. No sign of bone resorption was found in periapical radiographs. After the excision of lesion, histopathologic examination showed proliferation of Schwann cells, degenerative changes including nuclear atypia, hyalinization and myxoid areas and calcification. Immunohistochemical analysis revealed strong positive staining for S-100 protein. All these features were consistent with diagnosis of ancient schwannoma.

Langerhans Cell Histiocytosis Presenting as Protein Losing Enteropathy and Masquerading as Crohnʼs Disease

Purpose: Langerhans Cell Histiocytosis (LCH) is a rare disease with annual paediatric incidence of 2–5 cases per million per year. We report a case of LCH with gastrointestinal involvement. Methods: Retrospective analysis was done of a case presenting with bloody diarrhoea, vomiting and failure to thrive, diagnosed to be LCH and successfully treated. Results: 1 year 10 months old female child, product of non consanguineous marriage presented with relapsing course of loose motions (bloody in later course), vomiting (non bilious) and failure to thrive for 3 months, and fever with pedal edema for 1 month. There was no history of rash, jaundice, dermatitis, ear infection joint swelling or contact with Koch's. On physical examination child was malnourished (weight 8 Kg i.e. < 5 th percentile, height 83 cm i.e.25th percentile), had pallor, pedal edema and hepatosplenomegaly (liver 6 cm and spleen 2 cm below costal margin). Investigations revealed anaemia (Hb-8.7 gm/dl), deranged LFT (SGOT 57 IU/dl, SGPT 48 IU/dl, S.protein/albumin 3.1/1.5, triglycerides 909 mg/dl). Stool microscopy showed 25–30 pus cells, with mucus and RBCs. Mantoux test, Elisa for tuberculosis, immunoglobulin profile, HIV status, ANA, p-ANCA, were negative. Bone scan, chest x ray and skeletal survey were also negative. CT scan abdomen had hepatomegaly with small bowel edema. Liver biopsy showed marked steatosis. Repeated endoscopy showed duodenal ulcers and oedematous, friable colonic mucosa. Biopsy was suggestive of duodenal ulcers, chronic cryptitis with non-specific inflammation infiltrate, no inclusions granuloma/AFB. Barium meal follow through showed duodenal ulcer and segmental jejunal dilatations. Antisachromysis antibodies (ASCA) (IgA and IgG were positive). Thus in view of clinical symptoms, ASCA positivity (98% specificity) and endoscopic findings a diagnosis of CD was made. Patient showed improvement after onset of mesalamine and I/v methylprednisolone therapy. However persistent hepatosplenomegaly was unexplainable and suspicious and third biopsy of duodenal ulcer and colonic mucosa unveiled the mystery. Presence of cryptitis, inflammatory exudates and histiocytes (positive staining for S100 protein, CV 68 negative) was diagnostic of LCH. A bone marrow biopsy done thereafter showed infiltration by histiocytes. Patient responded to chemotherapy (LCH -II protocol for 1 year) and repeat endoscopy and bone marrow after chemotherapy was unremarkable. She's doing well presently on a follow up of 12 months post chemotherapy. Conclusion: Thus though the child was diagnosed as CD and even responded to treatment, a high index of suspicion due to persistent hepatosplenomegaly was the key factor leading to diagnosis of LCH with rare presentation with GIT symptoms.

Intraabdominal Schwannomas: A Single Institution Experience

IntroductionIntraabdominal schwannomas are rare, benign tumors. This study presents a single institution experience with 12 such tumors. MethodsBetween 1991 to 2006, 12 patients with a pathologically proven intraabdominal schwannoma were identified from a series of 216 mesenchymal tumors and were reviewed retrospectively. ResultsThere were nine females and three male patients with a median age of 58 years (range 35–88 years). Eleven patients were symptomatic, and the tumors were located in the stomach (n = 8), jejunum, colon, rectum, and lesser sac. Multiple preoperative investigations including endoscopies with biopsies and computed tomography (CT) scans were performed, but none yielded a correct definitive preoperative diagnosis. The median tumor size was 52 mm (range 18–95 mm). Pathological examination demonstrated the 11 gastrointestinal tract (GIT) schwannomas to be solid homogenous tumors, which were highly cellular and were composed of spindle cells with positive staining for S100 protein. The pathological appearance of the lesser sac schwannoma was distinct as it demonstrated cystic degeneration with hemorrhage and Antoni A and B areas on microscopy typical of soft tissue schwannomas. All 12 patients were disease-free at a median follow-up of 22 months (range 1–120 months). ConclusionIntraabdominal schwannomas are rare tumors, which are most frequently located within the GIT. GIT schwannomas are difficult if not impossible to diagnose preoperatively as endoscopic and radiologic findings are nonspecific. The treatment of choice is complete surgical excision because of diagnostic uncertainty, and the long-term outcome is excellent as these lesions are uniformly benign.

Prognostic value of S-100 immunostaining in tumour cells of non-small cell lung cancer

S-100 protein expression is present in various malignant tissues, yet its prognostic relevance is debatable. The aim was to assess in non-small cell lung cancer (NSCLC) patients’ prognostic value of S-100 protein considered alone or in relation with other variables. Tumour samples taken from 86 NSCLC patients during resection were assayed for S-100 protein expression with the use of polyclonal DAKO ZO311 antibody. S-100 expression was found in 32 cases (37%). Positive staining was not correlated with clinical characteristics including age, sex, pathology type of tumour, stage and cigarette smoking. There was a tendency for simultaneous expression of S-100 and P53 protein (p=0.06). A median survival rate for the entire group was 2.3 years (95% CI, 0.9–3.6 years). The median and 5-year survival of patients with positive staining for S-100 protein was 1.5 years and 25%, respectively, compared with 3.0 years and 35%, respectively, in the S-100 negative group (p=0.17). In the final model of a multivariate analysis, S-100 protein expression in tumour cells was associated with significantly decreased survival (p=0.005). S-100 protein expression in tumour cells seems to be an independent predictor of poor prognosis in NSCLC patients.

口蓋原発低悪性筋上皮腫例

A rare case of low grade malignant myoepithelioma arising in the minor salivary gland of the palate is reported. A 46-year-old man presented with a palate mass. Surgical resection was performed. Histological examination indicated that the tumor organized in the myoepithelial cells and showed signs of mitosis. Immunohistochemical studies showed positive staining for S-100 protein and cytokeratin. For nine months post operatively, there has not been any evidence of recurrence.