Radiation Therapy for Benign Disease: Arteriovenous Malformations, Desmoid Tumor, Dupuytren Contracture, Graves Ophthalmopathy, Gynecomastia, Heterotopic Ossification, Histiocytosis.

Although the use of ionizing radiation in malignant conditions has been well established, its application in benign conditions has not been fully accepted and has been inadequately recognized by health care providers outside of radiation therapy. Most frequently, radiation therapy in these benign conditions is used along with other treatment modalities, such as surgery, in instances where the condition causes significant disability or could even lead to death. Radiation therapy can be helpful for inflammatory/proliferative disorders. This article discusses the current use of radiation therapy in some of the more common benign conditions.

Outcome After Radiation Therapy for Langerhans Cell Histiocytosis Is Dependent on Site of Involvement.

PURPOSE: To characterize the efficacy and safety of radiation therapy in a contemporary Langerhans cell histiocytosis (LCH) cohort and to explore whether there are sites at higher risk for local recurrence. PATIENTS AND METHODS: Between 1995 and 2015 we identified 39 consecutive LCH patients who were treated primarily with radiation therapy. Patients were staged by single/multisystem involvement and established risk organ criteria. In 46 irradiated lesions, clinical and radiologic responses were evaluated at multiple time points after radiation therapy. Patient demographics, treatment, and local failure were compared by site of lesion. RESULTS: Median age at radiation therapy was 35 years (range, 1.5-67 years). Twelve patients had multisystem involvement, and of those, 5 patients had disease in organs considered to be high risk. The following sites were irradiated: bone (31), brain (6), skin (3), lymph node (3), thyroid (2), and nasopharynx (1). Median dose was 11.4 Gy (range, 7.5-50.4 Gy). At a median follow-up of 45 months (range, 6-199 months), local recurrence or progression was noted in 5 of 46 lesions (11%). There were no local failures of the 31 bone lesions evaluated, whereas the 3-year freedom from local failure in the 15 non-bone lesions was 63% (95% confidence interval 32-83%; P=.0008). Local failures occurred in 2 of 3 skin lesions, in 2 of 6 brain lesions, and 1 of 3 lymph node lesions. Deaths were recorded in 5 of 39 patients (13%), all of whom were adults with multisystem disease. CONCLUSION: Radiation therapy is a safe and effective measure for providing local control of LCH involving the bone. Whereas bone lesions are well controlled with low doses of radiation, disease in other tissues, such as the skin and brain, may require higher doses of radiation or additional treatment modalities.

Special variant of histiocytosis.

Indeterminate cell histiocytosis is a rare variant of histiocytosis. The diagnosis is currently based on presence and absence of immunohistochemical markers. The current case described an indeterminate cell histiocytosis with ETV3-NCOA2 translocation.

Crystal-storing histiocytosis masquerading ocular adnexal lymphoma: a case report and review of literature.

A case of crystal-storing histiocytosis (CSH) associated with mucosa-associated lymphoid tissue (MALT) lymphoma of orbit is reported. The patient was a 53-year-old man who presented with an 8-year history of a slowly enlarging tumor in his right orbit. Histopathologic examination revealed that the tumor was composed predominantly of sheets of spindle-shaped cells resembling striated muscle cells and scattered aggregates of atypical lymphoid cells, showing prominent plasmacytoid differentiation. Immunohistochemical analysis demonstrated that the spindle-shaped cells were CD68-positive histiocytes containing abundant crystals in their cytoplasm, consistent with the diagnosis of CSH. The aggregates of atypical lymphoid cells were diagnosed as MALT lymphoma based on their immunophenotype. Although CSH is a well-recognized manifestation in lymphoproliferative disorders, CSH complicated by MALT type of ocular adnexal lymphoma has rarely been reported. Given the rarity of this, every case presenting with such crystal-storing histiocytes warrants a thorough search for a hidden lymphoid dyscrasia.

Indeterminate cell histiocytosis successfully treated with narrowband UVB.

We present a 47-year-old man with a sudden eruption of more than 100 reddish-brown papules, which histologically exhibited a dense dermal proliferation of large mononuclear cells with vesicular nuclei and abundant pale cytoplasm. Electron microscopy and immunohistochemistry revealed findings consistent with indeterminate cell histiocytosis and the patient responded well to treatment with narrowband UVB therapy.

S100-negative indeterminate cell histiocytosis in an African American child responsive to narrowband ultraviolet B.

Indeterminate cell histiocytosis is a rare cutaneous disease characterized by the presence of dendritic cells that lack Birbeck granules and immunophenotypically shares features of both Langerhans cells and macrophages. We describe a case of a 4-year-old African American boy affected by a disseminated, exclusively mucocutaneous form of indeterminate cell histiocytosis. The eruption was successfully treated with narrowband ultraviolet B. The peculiar negativity of the Langerhans cell marker S100 is also discussed.

Indeterminate cell histiocytosis successfully treated with ultraviolet B phototherapy.

Indeterminate cell histiocytosis (ICH) is a rare disorder, characterized by infiltration of the skin by neoplastic cells that are characteristically positive for S-100 and CD1a, but lack Birbeck's granules. A 75-year-old man presented with a 4-year history of multiple papules on the trunk, limbs, face and neck. Skin biopsy revealed dense infiltration of histiocytic cells that were CD1a+/S100+, but lacked Birbeck's granules. No other abnormality was seen during a general examination including a computed tomography scan of the body, gallium scintigraphy, and an abdominal sonography. Broadband ultraviolet B (UVB) treatment was used for the skin lesions, and partial but almost complete remission was obtained. The case suggests that UVB phototherapy is an option for treatment of ICH.

Extranodal marginal zone B-cell lymphoma of the lacrimal gland associated with crystal-storing histiocytosis.

OBJECTIVE: Crystal-storing histiocytosis (CSH) is a very rare immunoglobulin (Ig) deposition disorder that can be associated with B-cell neoplasms as well as some reactive Ig-secreting lymphoproliferative disorders. This article reports the clinical, histopathologic, and molecular biologic findings of CSH in association with an extranodal marginal zone lymphoma (EMZL) of the lacrimal gland. DESIGN: Interventional case report with clinicopathologic correlation. INTERVENTION: Treatment consisted of conjunctival and orbital biopsies, as well as low-dose radiation of the left orbit. METHODS: Histopathologic findings of the conjunctival and orbital biopsies were compared. Further, extensive immunohistochemistry, polymerase chain reaction (PCR) for the detection of Ig heavy chain (IgH) gene rearrangement, Gene Scan analysis, and DNA sequencing were performed on all tissues. RESULTS: The tumor manifestations in the specimens demonstrated a similar morphologic and immunophenotypic characteristics consistent with the diagnosis of EMZL. Immunoglobulin H PCR and Gene Scan analysis showed B cells derived from the same clone. In association with the orbital EMZL were large accumulations histiocytes filled with refractile crystals, consistent with the diagnosis of CSH. CONCLUSIONS: The current case describes an EMZL of the lacrimal gland appearing 5 years after excision and low-dose radiation of a conjunctival lymphoma. The orbital recurrence was associated with surrounding CSH, a rare Ig storage disorder more often reported in patients with multiple myeloma or lymphoplasmacytic lymphoma or immunocytoma. Ophthalmic pathologists should be aware of the diagnosis when reviewing orbital biopsies, because difficulties may arise when the crystal-storing macrophages occupy more tissue space than the Ig-secreting cells or when they resemble cell types such as rhabdomyoblasts.

Histiocitosis en odontopediatría / Histiocytosis in pediatric dentistry

Las histocitosis infantiles son un grupo de enfermedades diversas y poco frecuentes, de etiología desconocida y de difícil diagnóstico clínico. Los estudios anatomopatológicos han permitido su clasificación y enfoque terapéutico. En casi todos los procesos que agrupa la histiocitosis, la boca puede presentar lesiones con una frecuencia de hasta el 70 por ciento, afecta los tejidos duros y blandos y a veces es el odontólogo el primero en observar al paciente. El objetivo de esta comunicación es realizar el diagnóstico diferencial de lesiones de histiocitosis, analizar su evolución con y sin tratamiento y orientar sobre su pronóstico. Sobre 13 niños de 1 a 14 años se siguió la evolución de las lesiones, se realizó el diagnóstico histopatológico y el tratamiento dentro de un equipo multidisciplinario

Childhood intracranial meningiomas after high-dose irradiation.

BACKGROUND: Irradiation, either alone or in association with other factors, is thought to play a role in the causation of intracranial meningioma. METHODS: The authors report two 15-year-old patients with convexity meningiomas as a result of high-dose irradiation received at a young age and review the English language literature reports of 13 pediatric patients with meningiomas after high-dose irradiation. The clinical characteristics of the 15 patients are presented. RESULTS: There were nine girls and six boys. The mean age at the time of irradiation was 2.5 years (2 months-9 years), and the mean age at diagnosis of meningioma was 13 years (5-15.5 years). The mean radiation dose was 4154 cGy (1500-8000 cGy). In 11 of the 15 patients, the meningioma was located in the calvarial area. Only 1 of 15 had multiple tumors, and only two of the tumors were clearly malignant at diagnosis. In ten patients, gross total resection was recorded, and two patients underwent subtotal resection. Three died of recurrent/disseminated meningiomas. CONCLUSIONS: This study suggests that meningiomas after high-dose radiation in children are mostly calvarial in location, rarely multiple, mostly benign in histologic type, and that complete removal is possible in most patients. The age at the time of radiation is young (mean age, 2.5 years) and the latent period is short (mean, 10.8 years). Although the clinical course of radiation-induced meningiomas in childhood generally is benign, high doses of radiation at a young age are to be avoided, and other means of therapy should be used if possible.

Systemic histiocytosis presenting as multiple sclerosis.

A patient resembling one with progressive multiple sclerosis in clinical presentation and by magnetic resonance imaging was studied in detail. Some features atypical for multiple sclerosis prompted a persistent search for an alternative cause. The diagnosis of a non-Langerhans systemic histiocytosis involving brain and bone was established and showed a partial response to radiation therapy. This patient illustrates the continued importance of a broad approach to the evaluation of possible multiple sclerosis, with particular attention to atypical features.