Mucosal Melanoma

Malignant Melanoma of the Sphenoid Sinus: Case Report and Literature Review

Malignant melanoma originating from the sphenoid sinus is an extremely rare but aggressive tumor of the head and neck. A 57-year-old man had a 1 month history of headache, right trigeminal paresthesias, and upper lid ptosis. Magnetic resonance imaging showed a large mass in the right sphenoid sinus and an invasion of the right cavernous sinus and clivus. The patient underwent endoscopic endonasal transsphenoidal surgery, and pathologically revealed malignant melanoma. One month after the operation, the patient was treated with radiation therapy. Unfortunately, the patient died of distant metastasis 2 years later. Due to its rarity, there is still no effective treatment strategy and no way to assess the progression of malignant melanoma.

Local intralesional talimogene laherparepvec therapy with complete local response in oral palatine mucosal melanoma: a case report

BACKGROUND

Mucosal melanoma, an aggressive type of malignancy different from the cutaneous melanomas commonly seen in the head and neck region, represents < 1% of all malignant melanomas. The pathogenesis of mucosal melanoma is unknown. Targetable mutations commonly seen in cutaneous melanoma, such as in the BRAF and NRAS genes, have a lower incidence in mucosal melanoma. Mucosal melanoma carries a distinct mutational pattern from cutaneous melanoma. Surgery with negative margins is the first-line treatment for mucosal melanoma, and systemic therapy is not well defined. Talimogene laherparepvec, an oncolytic viral immunotherapy, is United States Food and Drug Administration approved for the treatment of advanced malignant cutaneous melanoma, with local therapeutic benefits. Mucosal melanoma was initially excluded from talimogene laherparepvec's initial phase III clinical trial.

CASE PRESENTATION

We present the case of a white female patient in her 40s with past medical history of systemic lupus erythematous, scleroderma, and estrogen-receptor-positive invasive ductal breast carcinoma. Following a bilateral mastectomy, the patient was found to have BRAF-negative mucosal melanoma of her hard palate with a soft palate skip lesion. Owing to the presence of a skip mucosal lesion as well as the anticipated defect and need for free-flap reconstructive surgery, nonsurgical management was considered. The patient was referred to medical oncology, where-based on the patient's complicated medical history and the risk of immunotherapy possibly worsening her prior autoimmune diseases-local talimogene laherparepvec injections were chosen as the primary therapy for her mucosal lesions. Though talimogene laherparepvec is approved for the treatment of cutaneous melanoma, there are limited data available on the use of talimogene laherparepvec in mucosal melanomas.

CONCLUSION

The patient had a complete local tumor response at both the primary lesion as well as the skip lesion with the local injections. She had no side effects and maintained a high quality of life during treatment.

Electrochemotherapy as adjuvant treatment in a sinonasal mucosal melanoma in elderly patient: a case report

BACKGROUND

Sinonasal Mucosal Melanoma (SNMM) is a rare but aggressive disease. Surgery with free margins, when feasible, is the treatment of choice. In the last three decades, electrochemotherapy (ECT) has emerged as a local ablative procedure, performed with the Cliniporator, for cutaneous and mucosal tumours of different histology. We present a case report of an ECT treatment performed by means of a new endoscopic electrode, on an elderly patient affected by primary SNMM.

METHODS

An 88-year-old man with a diagnosis of SNMM (cT4aN0M0)-Stage IV, of the left nasal fossa presented at our institution. Symptoms were epistaxis and complete left nasal obstruction. He refused sinonasal extended surgery and radiotherapy. He underwent a tumor debulking followed by ECT exclusively for symptom control, with palliative intent.

RESULTS

The patient underwent SNMM debulking under general anaesthesia, followed by ECT on tumour margins. After the procedure, he had been free from symptoms for 5 months, with a good quality of life. Local recurrence was controlled with a new local debulking and ECT procedure on margins. The patient remained symptom free for the next 4 months. Seventeen months after diagnosis, the patient is mild symptomatic for sinonasal disease. Therefore, he developed a systemic disease progression.

CONCLUSIONS

In our experience, ECT can be used as an adjuvant tool for symptom and local control in SNMM when extended surgery is out of curative intent or unfeasible. As expected, ECT does not appear to have any effect on systemic disease progression.

Multidisciplinary approach and treatment of acral and mucosal melanoma

Acral and mucosal melanoma are uncommon variants of melanoma. Acral melanoma has an age-adjusted incidence of approximately 1.8 cases per million individuals per year, accounting for about 2% to 3% of all melanoma cases. On the other hand, mucosal melanoma, with an incidence of 2.2 cases per million per year, makes up around 1.3% of all melanoma cases. These melanomas, in addition to being biologically and clinically distinct from cutaneous melanoma, share certain clinical and pathologic characteristics. These include a more aggressive nature and a less favorable prognosis. Furthermore, they exhibit a different mutational pattern, with KIT mutations being more prevalent in acral and mucosal melanomas. This divergence in mutational patterns may partially account for the relatively poorer prognosis, particularly to immune checkpoint inhibitors. This review explores various aspects of acral and mucosal melanoma, including their clinical presentation, pathologic features, mutational profiles, current therapeutic approaches, outcomes associated with systemic therapy, and potential strategies to address resistance to existing treatments.

Mucosal Melanoma Clinical Management and Prognostic Implications: A Retrospective Cohort Study

Mucosal melanoma (MM) is an uncommon melanoma subtype affecting mucosal surfaces of the head and neck, anorectal region, and vulvovaginal area. We aimed to present our experience at a tertiary-level hospital regarding MM diagnosis, management, monitoring of progression, mutations, and outcome predictors. We performed a registry-based cohort study including MM cases diagnosed from 2012 to 2022 and retrospectively characterized somatic mutations on BRAF, NRAS and c-KIT. We employed Kaplan-Meier curves, log-rank tests, and Cox regression analysis to explore prognostic factors and survival outcomes in a cohort of 35 patients, mainly women (63%) with a median age of 70 years. Predominantly, MM occurred in the vulvovaginal region (48.6%). At diagnosis, 28.6% had lymph node involvement, and 31.4% also had distant metastasis. Mutations in BRAF and c-KIT were identified in 3/35 (9%) and 2/6 patients (33%), respectively. Surgery was performed in 71.4% of patients, and most received systemic treatment (65.7%). Lower disease stage, thinner Breslow depth, and surgical resection were associated with improved overall survival. Notably, age, sex, radiotherapy, and BRAF mutant status did not affect survival. Standard management typically involves immunotherapy. Cases with BRAF or c-KIT mutations may be considered for targeted therapies. Unfortunately, MM prognosis remains unfavorable, with a less than 50% survival rate at 2 years.

Combinations of EGFR and MET inhibitors reduce proliferation and invasiveness of mucosal melanoma cells

Mucosal melanoma (MM) is a very rare and aggressive type of cancer for which immunotherapy or targeted therapy such as BRAF/MEK inhibitors, used in cutaneous melanoma, usually fail. Due to our earlier experience showing the high effectiveness of epidermal growth factor receptor (EGFR) and hepatocyte growth factor receptor (MET) inhibitors in reducing the activation of the MAPK and PI3K/AKT signalling pathways, we aim to test whether these drugs would also be effective for mucosal melanoma. Cells representing two commercially available mucosal melanoma cell lines (GAK and HMVII) and one cell line obtained from a patient's vaginal melanoma were treated with MET or EGFR inhibitors, or combinations of these agents. The dual-inhibitor treatment strategy resulted in a decrease of cell proliferation, migration and invasion. Moreover, combinations of inhibitors led to reduction of pEGFR/EGFR and pMET/MET ratio and downregulation of PI3K/AKT and MEK/ERK1/2-based signalling pathways. Our findings indicate a potential therapeutic strategy based on EGFR and MET inhibitors in mucosal melanoma, which should be further evaluated in vivo and in clinical experiments. They also suggest that targeting multiple receptor tyrosine kinases may block signalling crosstalk and possibly delay the appearance of resistance to kinase inhibitors in mucosal melanoma cells.

Demographics, Clinical Characteristics and Survival Outcomes of Primary Urinary Tract Malignant Melanoma Patients: A Population-Based Analysis

All primary urinary tract malignant melanoma (ureter vs. bladder vs. urethra) patients were identified from within the Surveillance, Epidemiology, and End Results (SEER) database 2000-2020. Kaplan-Maier plots depicted the overall survival (OS) rates. Univariable and multivariable Cox regression (MCR) models were fitted to test the differences in overall mortality (OM). In the overall cohort (n = 74), the median OS was 22 months. No statistically significant or clinically meaningful differences were recorded according to sex (female vs. male; p = 0.9) and treatment of the primary (endoscopic vs. surgical; p = 0.6). Conversely, clinically meaningful but not statistically significant (p ≥ 0.05) differences were recorded according to the patient's age at diagnosis (≤80 vs. ≥80 years old; p = 0.2), marital status (married 26 vs. unmarried 16 months; p = 0.2), and SEER stage (localized 31 vs. regional 14 months; p = 0.4), and the type of systemic therapy (exposed 31 vs. not exposed 20 months; p = 0.06). Finally, in univariable and MCR analyses, after adjustment for the SEER stage and type of systemic therapy, tumor origin within the bladder was associated with a three-fold higher OM (Hazard ratio: 3.00; p = 0.004), compared to tumor origin within the urethra. In conclusion, primary urinary tract malignant melanoma patients have poor survival. Specifically, tumor origin within the bladder independently predicted a higher OM, even after adjustment for the SEER stage and systemic therapy status.

Sinonasal mucosal melanoma with smooth muscle differentiation: a potential pathological diagnostic pitfall

BACKGROUND

Sinonasal mucosal melanoma (SNMM) is a rare malignant melanoma originating from melanocytes derived from multipotent neural crest cells. Its incidence accounts for less than 1 % of all malignant melanomas, with five-year survival rate about 25 %. Occasionally, it is incredibly formidable to make a compelling diagnosis when malignant melanoma with other diverse differentiation.

CASE PRESENTATION

Herein, we presented a 54-year-old male case of SNMM with smooth muscle differentiation, defined by histopathology and positive immunostaining for the smooth muscle specific markers of a-SMA, H-caldesmon, calponin and Desmin, as well as specific melanocyte markers of HMB-45, Melan-A, SOX10, and PNL2.

CONCLUSIONS

Mucosal melanoma with smooth muscle differentiation is remarkably infrequent, and reported only 4 cases to date. It would be a potential pathological diagnostic pitfall. It is important to understand this variation of malignant melanoma for avoiding misdiagnosis.

Primary melanoma of submandibular gland: case report and literature review of a very rare entity

Background

Cutaneous melanomas account for more than 95% of all cases of primary melanoma, making non-cutaneous primary melanomas truly rare. Cases of primary mucosal melanomas of the oral cavity have been widely described; however, instances of primary melanomas arising from salivary glands have been rarely described. To date, this is only the second case of primary melanoma of the submandibular gland.

Case presentation

This is a report of a case of a 36-year-old healthy male patient, who was referred to us with the chief complaint of a growing swelling on the left side of his lower jaw. Evaluations revealed an evident facial asymmetry in the frontal view with a firm, non-tender swelling. Initial orthopantomogram did not reveal any alterations in the trabeculation or morphology of the jaws and the surrounding structures. A soft tissue ultrasonography of the left submandibular gland and anterior region of mandible revealed a hypoechoic cystic mass with numerous micro-echoes. Further para-clinical examinations yielded the definitive diagnosis of primary melanoma of the submandibular gland. Moreover, no evidence of distant osteometastasis was observed in whole-body scans. Subsequent surgical management with the approach of excising the submandibular salivary gland and concurrent selective neck dissection was implemented.

Conclusions

This report emphasizes the importance of thorough examination and prompt referral to designated specialists in cases with suspicious behaviors which are unresponsive to treatments. It can be further concluded that melanoma can mimic a range of benign pathologies; therefore, putting it in the list differential diagnosis of similar lesions seems plausible.

Toripalimab (anti-PD-1) versus High-Dose Interferon-α2b as Adjuvant Therapy in Resected Mucosal Melanoma: A Phase II Randomized Trial

BACKGROUND

No standard of care for mucosal melanoma (MM) in the adjuvant setting has been established. Meanwhile, relapse-free survival (RFS) is only about five months after surgery alone. This phase II trial aimed to compare toripalimab vs. high-dose interferon-α2b (HDI) as an adjuvant therapy for resected MM.

PATIENTS AND METHODS

From July 2017 to May 2019, 145 patients with resected MM were randomized (1:1) to receive HDI (N = 72) or toripalimab (N = 73) for one year until disease relapse/distant metastasis, unacceptable toxicity, or withdrawal of consent. The primary endpoint was RFS. The secondary endpoints included distant metastasis-free survival (DMFS), overall survival (OS), and safety.

RESULTS

After a median follow-up of 26.3 months, the numbers of RFS, OS, and DMFS events were 51 vs. 46, 33 vs. 29, and 49 vs. 44 in the toripalimab arm and the HDI arm, respectively. The median RFS were 13.6 (95%CI: 8.31-19.02) months and 13.9 (95%CI: 8.28-19.61) months in the toripalimab arm and HDI arm, respectively. The DMFS was not significantly different between the two arms (HR: 1.00, 95%CI: 0.65-1.54). The median OS was 35.1 months (95%CI: 27.93-NR) in the toripalimab arm, with no significant difference in all-cause death (HR: 1.11, 95% CI: 0.66-1.84) for the two arms. The median sums of the patients' actual infusion doses were 3672 mg and 1054.5 MIU in the toripalimab arm and HDI arm, respectively. The incidence of treatment-emergent adverse events with a grade ≥ 3 was much higher in the HDI arm than in the toripalimab arm (87.5% vs. 27.4%).

CONCLUSION

Toripalimab showed a similar RFS and a more favorable safety profile than HDI, both better than historical data, suggesting that toripalimab might be the better treatment option. However, additional translational studies and better treatment regimens are still warranted to improve the clinical outcome of MM.

Proliferation Marker Ki67 as a Stratification Index of Adjuvant Chemotherapy for Resectable Mucosal Melanoma

Background

Adjuvant chemotherapy has been shown to produce a favorable prognosis for patients with resectable mucosal melanoma (MM), resulting in the need for stratification to optimally select patients to benefit from adjuvant therapy. This study analyzed Ki67 as a potential stratification index for adjuvant chemotherapy in resectable MM.

Methods

Patients with resected MM who received subsequent adjuvant therapy in Beijing Cancer Hospital between 2010 and 2018 were retrospectively enrolled and analyzed. Relapse-free survival (RFS) and melanoma-specific survival (MSS) curves were used to perform the survival comparisons across different subgroups.

Results

From Jan 2010 to Dec 2018, 1106 MM patients were screened from a database of 4706 patients and 175 of these patients were finally enrolled. A total of 100 patients received temozolomide (TMZ)-based adjuvant chemotherapy and 75 patients received high-dose interferon-α2b (HDI) adjuvant therapy. Compared with HDI, patients who received TMZ-based adjuvant chemotherapy had significantly superior RFS (21.0 vs. 9.6 months, P = 0.002). For patients with low Ki67 expression (&lt;30%), the two regimens showed no significant difference for impact on RFS (33.9 vs. 22.7 months, P = 0.329). However, for patients with high Ki67 expression (≥30%), TMZ-based adjuvant chemotherapy achieved favorable RFS compared with HDI (18.0 vs. 6.7 months, P &lt; 0.001) and tended to improve MSS compared to HDI (41.4 vs. 25.1 months, P = 0.067).

Conclusion

Compared with HDI, adjuvant chemotherapy may be more relevant for patients with Ki67 ≥ 30%. Ki67 may serve as a potential index to distinguish populations benefiting from adjuvant chemotherapy in resectable MM, and may provide a basis for stratification in the selection of adjuvant regimens.