Melan-A as a useful diagnostic immunohistochemical stain for the diagnosis of primary sinonasal melanomas

PET/CT Imaging in Treatment Planning and Surveillance of Sinonasal Neoplasms

Sinonasal cancers are uncommon malignancies with a generally unfavorable prognosis, often presenting at an advanced stage. Their high rate of recurrence supports close imaging surveillance and the utilization of functional imaging techniques. Whole-body 18F-FDG PET/CT has very high sensitivity for the diagnosis of sinonasal malignancies and can also be used as a "metabolic biopsy" in the characterization of some of the more common subgroups of these tumors, though due to overlap in uptake, histological confirmation is still needed. For certain tumor types, radiotracers, such as 11C-choline, and radiolabeled somatostatin analogs, including 68Ga-DOTATATE/DOTATOC, have proven useful in treatment planning and surveillance. Although serial scans for posttreatment surveillance allow the detection of subclinical lesions, the optimal schedule and efficacy in terms of survival are yet to be determined. Pitfalls of 18F-FDG, such as post-surgical and post-radiotherapy crusting and inflammation, may cause false-positive hypermetabolism in the absence of relapse.

Biphenotypic sinonasal sarcoma: demographics, clinicopathological characteristics, molecular features, and prognosis of a recently described entity

Biphenotypic sinonasal sarcoma (BSNS) is a recently recognized type of sarcoma arising exclusively in the sinonasal tract displaying unique clinical course, histopathology, and genetics. Due to its rarity, only case series and case reports are available. In order to provide an overview of the current understanding of this disease, we present a comprehensive review of the literature and present three previously unreported cases of BSNS. A total of 55 genetically characterized and 41 cases without molecular data were identified in the literature. Two-thirds of patients were female and the peak incidence was in the fifth decade. Fatal outcome was rare (two cases with intracranial extension) and local recurrence occurred in 31.6%, all occurring within 5 years after initial treatment. Histologically, BSNS is highly cellular in the majority of cases and composed of fascicles of spindle cells, with entrapped hyperplastic surface epithelium being a frequent finding. The immunohistochemical profile is characteristic due to the biphasic nature of this lesion, with shared features of both myogenic and neural origin. Rhabdomyoblastic differentiation is apparent in a subset of cases. The most common genetic event is the PAX3-MAML3 fusion (58.6%) but isolated PAX3 rearrangement (19.2%), absence of rearrangements (9.1%), PAX3-FOXO1 (8.1%), PAX3-NCOA1 (4%), and isolated MAML3 rearrangement (2%) have also been reported. In conclusion, the recognition of BSNS is crucial due to its relatively indolent clinical course. A selected immunohistochemical panel and/or molecular confirmation can be used to aid in appropriate diagnosis and consequently in prognostication and to avoid overtreatment with chemotherapy regimens used in its mimics.

Primary sinonasal mucosal melanoma simulated as cystic lesions: a case report

Sinonasal mucosal melanoma (SNMM) in the maxillary sinus is a rare disease condition. Compared to oral mucosal melanoma, SNMM has a bulky, exophytic, and polypoid appearance, is weakly pigmented, and associated with unspecific symptoms. Due to these features, SNMM in the maxillary sinus has been misdiagnosed as nasal polyps and chronic sinusitis. In this case report, we described SNMM occurring in the right maxillary sinus simulated as a cystic or benign lesion. Cortical bone thinning and expansion were observed around the mass. The excised soft mass was encapsulated and weakly pigmented. The mass was clearly excised and covered with a pedicled buccal fat pad graft. Diagnosis using immunohistochemistry with S-100 and homatropine methylbromide-45 (HMB-45) is critical for proper treatment.

Melanoma Masquerading as a Zosteriform Rash

BACKGROUND Primary care physicians and internal medicine specialists frequently encounter a variety of rashes. Many of these cases look and feel typical of common entities, resulting in the potential for misdiagnosis. CASE REPORT This is a case of a zosteriform rash where the surprising true diagnosis of metastatic melanoma was confirmed with bedside skin punch biopsy. Possible mechanisms involve direct cutaneous injury, neuronal, and dorsal root ganglia involvement in metastases. CONCLUSIONS Skin biopsy is indispensable especially when there is a lack of clinical response or deterioration in the clinical condition. The pathophysiology of zosteriform metastasis is unclear.

Outcome of sinonasal melanoma: clinical experience and review of the literature

BACKGROUND

Primary sinonasal malignant melanoma (SNMM) is a rare clinical entity. There is neither a classification nor a staging system nor an evidence-based treatment concept established. Our objective was to find potential risk factors predicting the outcome.

METHODS

Twenty-five patients with histologically confirmed SNMM were consecutively included and retrospectively analyzed. Staging methods were nasal endoscopy, CT, MRI, and positron emission tomography (PET) scan. Patients were selected for a curative or palliative concept. All patients had postoperative follow-up with control-MRI at 3 and 6 months. Restaging was performed when local recurrence occurred.

RESULTS

Nineteen patients underwent primary surgery with curative intention; in 16 cases with tumor free margins. Thirteen patients (68%) had transnasal endoscopic surgery, 4 lateral rhinotomy, and 2 transfacial approach with orbital exenteration. Six patients (32%) had palliative therapy and 7 patients (37%) had adjuvant radiotherapy. Despite radical operations, 6 patients (37%) showed local recurrence and 8 patients (50%) developed distant metastasis. In 2 patients with incomplete surgery, regional metastasis was noted. The median disease-free interval was 18 months, and the median overall survival rate was 23 months.

CONCLUSION

SNMMs of the ethmoid and maxillary sinuses have a worse prognosis than other localizations in the nasal cavity; infiltration into the skull base, orbit, or facial soft tissue correlates with a very poor outcome corresponding to the palliative situations. Furthermore, local recurrence insinuates aggressive disease with short survival rate. A main difference from its cutaneous counterpart seems to be a primary tendency to hematogenic spread. Further research is needed to confirm these findings.

Toward a better understanding of sinonasal mucosal melanoma: clinical review of 23 cases

BACKGROUND

Primary sinonasal mucosal melanoma is a rare disease, occurring far less often than cutaneous lesions. The objective of this study was to review the records of patients diagnosed with primary sinonasal mucosal melanoma.

METHODS

We performed a retrospective review of the medical records of 23 patients with sinonasal mucosal melanoma who were treated at Taipei Veterans General Hospital between 1982 and 2002.

RESULTS

Sixteen of the 23 patients were male and 7 were female; their mean age was 68.2 years (range, 39-87 years). At diagnosis, the melanoma was limited to lesions located in the sinonasal area in 20 patients, and had spread in 3 patients. Local recurrence developed in 9 patients, neck metastasis in 5, and distant metastasis in 19. The 5-year disease-specific survival and local control rates were 22.26% and 52.30%, respectively.

CONCLUSION

In our experience, primary sinonasal mucosa melanoma is prone to spread from the site of origin. The major obstacle in improving overall survival is achieving systemic control.

Cancer of the nasal cavity and paranasal sinuses

Sinonasal malignancies continue to have poor survival rates. Disease-related mortality is usually the result of disease recurrence and progression at the primary site despite aggressive therapy. Complete surgical excision with postoperative radiation therapy remains the standard of care for resectable lesions. Improved reconstructive techniques have increased our ability to aggressively clear locally advanced disease in this anatomically challenging region, while reducing associated functional and cosmetic morbidity. Intensive multimodality treatment regimens coupled with newer medical technology may ultimately improve the long-prevailing poor prognosis of these tumors.

Current management of mucosal melanoma of the head and neck

While mucosal-based melanomas of the head and neck region are uncommon lesions, when they do arise they usually follow an inexorably aggressive course. Experience with these tumors is, necessarily, limited; as such, well-worked out treatment protocols for the treatment of such lesions are in short supply. It appears as though mucosal melanomas (MuMs) develop more frequently in the nasal cavity and paranasal sinus region, and less often in the oral cavity. It seems that the incidence of nodal metastasis is significantly lower for sinonasal MuMs than it is for MuMs of the oral cavity; this observation may influence decisions about performing neck dissection as a function of location of the primary MuM. At present, surgical excision remains the mainstay of treatment; however, anatomical complexities within the region can hamper attempts at complete excision. Radiotherapy has not traditionally been relied on for routine treatment of MuM, although some recent reports have challenged this view. Chemotherapy is, at present, employed principally in the treatment of disseminated disease and for palliation. As a diagnostic matter, MuM belongs to the class of tumors that, on light microscopy, may with some regularity be confused with other malignancies (including sarcomas, plasmacytomas, and carcinomas); as a consequence, this is a diagnosis which is often best confirmed by way of ancillary testing via immunohistochemical studies. A better grasp of the best means of treating MuM will likely come only when large referral centers are able to pool their experiences with these uncommon yet virulent malignancies.