Langerhans' cell histiocytosis of the temporal bone

Mucosal melanocytic lesion in the middle ear extending to the inner ear and nasopharynx

Benign dendritic melanocytic proliferation is usually observed in the skin. We report an extremely rare case of a melanocytic lesion in the middle ear mucosa. Only 3 cases of melanocytic lesions in the middle ear have been reported. Our report is the only one that describes an adult with a melanocytic lesion in the middle ear that extended to the inner ear and nasopharyngeal mucosa. A 23-year-old female presented with profound sensory neural hearing loss and recurrent discharge from the right ear. Examination revealed a blue right tympanic membrane with a small perforation. Computed tomography scans and magnetic resonance imaging were performed. After surgical exploration and histopathological examination, the patient was found to have a benign melanocytic lesion in the right middle ear. Melanocytic lesions are commonly found in the skin. There are no previous reports have described adult patients with melanocytic lesions in the middle ear that extend to the inner ear and nasopharynx, which cause profound hearing loss with recurrent ear discharge. These patients require regular follow-up to assess the progression of the lesion and to watch for any malignant behavior.

Incidental finding of Langerhans cell histiocytosis of temporoparietal bone - A case report

Introduction and importance

Langerhans cell histiocytosis (LCH) is a rare haematological disorder affecting infants and young children and has an estimated incidence of 2-5 cases per million people per year. LCH invades the reticuloendothelial system and causes the proliferation of Langerhans cells and mature eosinophils. LCH involving the temporoparietal bone has rarely been reported in the literature.

Presentation of case

A ten-year-old boy presented to the Neurosurgical outpatient clinic with a swelling on the right temporoparietal region following a fall from his bicycle. Local examination revealed a single, 3 × 3 cm, non-tender, cystic, immobile swelling in the right temporoparietal region. On evaluation for recent head trauma, an incidental finding of eosinophilic granuloma was discovered on a CT scan. The FNAC was suggestive of a histiocytic lesion pertaining to a diagnosis of LCH. The patient underwent wide excision of the mass and cranioplasty. A one-month follow-up CT scan of the head had no evidence of residual or recurrent disease.

Discussion

Eosinophilic granuloma is one of the three variants of LCH and has a relatively better prognosis. Clinical diagnosis can be challenging and mandates tissue sampling for histopathological examination. Treatment modalities including surgery, radiotherapy, chemotherapy, and steroid injection are used alone, or in combination, depending on the extent and severity of the disease.

Conclusion

Examining a swelling in the temporoparietal region with no other characteristic symptoms could be a case of LCH. The timely diagnosis and surgical excision with other adjuvant treatment options of this rare pediatric disease would help in a better outcome.

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Langerhans cell histiocytosis can present as a mass in the temporal or parietal region with no symptoms otherwise.

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The etiology of Langerhans cell histiocytosis is still unknown and diagnosis can be challenging.

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The prognosis depends greatly on early identification and prompt surgical treatment.

Otologic Manifestations of Langerhans Cell Histiocytosis: A Systematic Review

OBJECTIVE

To perform a systematic review to investigate common otologic manifestations of Langerhans cell histiocytosis, the incidence of these findings, methods for diagnosis, as well as medical and surgical management.

DATA SOURCES

PubMed/MEDLINE, Embase, and Cochrane Library.

REVIEW METHODS

A search of PubMed/MEDLINE, Embase, and Cochrane Library for all articles published between 1963 to 2020 was performed with variations and combinations of the following search terms: Langerhans cell histiocytosis, eosinophilic granuloma, Letterer-Siwe, Hand-Schüller-Christian, otitis, otologic, ear. A review of the references of all included articles was also conducted.

RESULTS

Sixty-two articles encompassing 631 patients met inclusion criteria. Otologic symptoms at presentation were found in 246 (39%) patients in the reported studies with 48% reporting bilaterality. The mean age was 14.8 years with a male predominance (64%). The most common otologic presenting symptom was otorrhea (46%). A majority had the multisystem variant (52%). The most common treatment modalities were chemotherapy (52%), followed by surgery (50%), systemic steroids (45%), and radiotherapy (31%). Surgery was performed in 75.8% with unisystem involvement and in 50.6% with multisystem involvement. The most effective treatments included radiotherapy (56% success rate, 17% of treated patients), systemic steroids (44% success, 20% treated), chemotherapy (41% success, 21% treated), and surgical modalities (36% success, 19% treated).

CONCLUSIONS

Otologic manifestations that occur with the multisystem variant or are at high risk for central nervous system involvement necessitate systemic treatment. For unifocal lesions, surgery is recommended. Lastly, radiotherapy should be reserved for extensive lesions involving vital structures or presenting in older patients.

Differentiating Pediatric Rhabdomyosarcoma and Langerhans Cell Histiocytosis of the Temporal Bone by Imaging Appearance

BACKGROUND AND PURPOSE

Rhabdomyosarcoma and Langerhans cell histiocytosis are malignant lesions that can affect the skull base with similar radiographic characteristics on CT and MR imaging. We hypothesized that location within the temporal bone determined radiographically can provide useful adjunctive information in differentiating these distinct neoplasms.

MATERIALS AND METHODS

We identified patients with Langerhans cell histiocytosis and rhabdomyosarcoma by using an imaging data base and International Classification of Diseases, Ninth Revision codes at a tertiary care academic medical center. Cross-sectional images were reviewed by a neurotologist and neuroradiologist, who evaluated the location of the lesions and scored each subsite-middle ear, mastoid, petrous apex, retrosigmoid/posterior fossa-on a scale of 0 (no involvement), 1 (partial), or 2 (complete involvement).

RESULTS

We identified 12 patients representing 14 cases of Langerhans cell histiocytosis, and 9 patients representing 9 cases of rhabdomyosarcoma. For patients with Langerhans cell histiocytosis, mastoid involvement was rated 23/28 (82%) compared with 6/18 (33%) with rhabdomyosarcoma (P = .001). Langerhans cell histiocytosis was present in only the anterior portion of the temporal bone (petrous apex and middle ear) in 1 case (7.1%) and in the anterior portion of the temporal bone only in 5/9 (55%) cases of rhabdomyosarcoma (P = .018). The cortical bone was more commonly involved in Langerhans cell histiocytosis, 11/28 (39%) of cases compared with 2/18 (11%) cases in rhabdomyosarcoma (P < .05).

CONCLUSIONS

These results indicate that lesions involving only the anterior portion of the temporal bone (petrous apex and middle ear) are more likely to be rhabdomyosarcoma. Lesions involving the mastoid are more likely to be Langerhans cell histiocytosis. This difference in primary location may be helpful in predicting the pathology of these lesions on the basis of imaging.

Langerhans Cell Histiocytosis of the Temporal Bone

Langerhans cell histiocytosis involving the temporal bone region is uncommon and can resemble malignant neoplasms on imaging due to high cellularity. Although recognizing the presence of sharp margins with beveled-edges can be helpful, tissue sampling is often necessary for confirming the diagnosis. Cytology classically demonstrates kidney-bean shaped nuclei within the Langerhans cells and immunohistochemical staining is positive for S-100, peanut agglutinin (PNA), MHC class II, CD1a, and Langerin (CD 207). These features are exemplified in this sine qua non radiology-pathology correlation article.