RARE-10. Neurocutaneous melanocytosis-associated hydrocephalus: the MSK experience from 2001-2022

OBJECTIVE: We hypothesize that patients with neurocutaneous melanocytosis-associated melanoma and ventriculoperitoneal shunts are at risk of developing intraperitoneal spread of melanoma. BACKGROUND: Neurocutaneous melanocytosis, a rare condition characterized by excessive proliferation and deposition of melanocytes in the leptomeninges and brain parenchyma, typically occurs in children with large congenital melanocytic nevi and multiple smaller congenital nevi. These patients are at heightened risk for developing NRAS+ melanomas in the central nervous system, which in turn may lead to symptomatic hydrocephalus requiring cerebrospinal fluid diversion for symptom relief. METHODS: Retrospective single-institution study of patients with histologically or radiographically confirmed NCM evaluated at Memorial Sloan Kettering Cancer Center (MSKCC) from 2001-2022. RESULTS: Of the 47 patients with a diagnosis of NCM, 44 patients had symptomatic neurological complications. Eleven patients developed hydrocephalus, 10 had CNS melanoma, and required ventriculoperitoneal shunt placement. Nine of the 10 patients ultimately died of their disease. Three patients were diagnosed with intraperitoneal melanoma, though data are unavailable for the remaining eight. CONCLUSIONS: All (n=11) patients with NCM-associated CNS melanoma required VP shunts for symptomatic relief. Ten of these patients died within 4.3 years of VP shunt placement, with a range of 1 month to 13.5 years prior to succumbing to their disease. While the intraperitoneal pathology remains unknown for 7 of the cases, 3 had confirmed intraperitoneal melanoma, suggesting that VP shunts provided the conduit to CNS melanoma seeding of the peritoneum. Obtaining baseline abdominal imaging studies prior to VP shunt placement may be helpful in the follow-up of these patients.

Neurocutaneous melanocytosis-associated malignant melanoma presenting with peritoneal seeding

Neurocutaneous melanocytosis (NCM) is characterized by melanocyte deposition in the leptomeninges and brain parenchyma, primarily occurring in children with large or giant congenital melanocytic nevi (LCMN) or multiple congenital melanocytic nevi. Patients with NCM may develop hydrocephalus and increased intracranial pressure, which can be managed with ventriculoperitoneal (VP) shunting. We present the case of a 16-month-old girl who developed peritoneal carcinomatosis and malignant ascites following VP shunting for hydrocephalus secondary to NCM to increase awareness of this rare, but serious, complication of cerebrospinal fluid diversion.

NCOG-60. MALIGNANT MELANOMA IN NEUROCUTANEOUS MELANOCYTOSIS: A RETROSPECTIVE CASE SERIES (2000-2020)

Neurocutaneous melanocytosis (NCM) is a rare neurocutaneous syndrome which typically develops in children with large congenital melanocytic nevi (LCMN) and excessive melanocyte proliferation in the leptomeninges and brain parenchyma. Malignant melanoma develops in an estimated 2.3% of patients with LCMN and 40-60% of patients with NCM. NCM-associated melanomas frequently harbor NRAS mutations with no well-established role for targeted therapy. In a retrospective, single-institution study, we reviewed eleven patients with NCM-associated CNS melanoma evaluated at Memorial Sloan Kettering Cancer Center from June 2000 to January 2020. Five patients had previously identified focal melanocytosis prior to developing melanoma. In this subgroup, the median time from identification of focal melanocytosis to melanoma diagnosis was 80 months (range: 18-200). Median age at melanoma diagnosis was 9.9 years (range: 1.1-25.3). Presentation at the time of diagnosis with CNS melanoma included headache (45%), focal deficits (45%), and seizure (18%). Eight patients had hydrocephalus (73%). Five patients presented with a focal mass (45%) and six patients had focal or diffuse leptomeningeal disease without a mass (55%). Leptomeningeal spread eventually developed in all patients. Where molecular testing was available, three melanomas had NRAS mutations and none were associated with BRAF mutations. Seven patients were treated with cancer-directed therapy including temozolomide, trametinib, ipilimumab, and nivolumab, with each therapy being administered to two patients. Radiation therapy was used in three patients, including whole brain radiation therapy and stereotactic radiosurgery. Median survival from melanoma diagnosis was 9.1 months (range: 1-60.4). The longest surviving patient was initially diagnosed with cutaneous melanoma, surviving 60.4 months after diagnosis with cutaneous melanoma and 22.7 months after diagnosis with CNS melanoma. Prognosis remains guarded in patients with NCM-associated melanoma, and further investigation is warranted to identify effective management strategies.

Disparities in tuberculosis between Asian/Pacific Islanders and non-Hispanic Whites, United States, 1993-2006

SETTING

The United States (US) National Tuberculosis Surveillance System (NTSS), including 50 states, District of Columbia, and New York City.

OBJECTIVE

To examine disparities in characteristics and rates of Asian/Pacific Islander (API) and non-Hispanic White tuberculosis (TB) patients.

DESIGN

Descriptive analysis and logistic regression of selected 1993-2006 NTSS data. US Census Bureau Zip Code Tabulation Areas and geographic information system were used to compare API and non-Hispanic White TB patients by population density.

RESULT

Of 253,299 TB cases, 19.8% were APIs and 23.2% were Whites; 94.2% APIs and 11.9% Whites were foreign-born. Factors that were most often associated with APIs were being female, age 15-24 years, extra-pulmonary TB, and drug resistance. APIs were less likely than Whites to be human immunodeficiency virus (HIV) positive, homeless, substance abusers, or on directly observed therapy. From 1993 to 2006, the API TB case rate declined by 42.9% vs. 66.6% in Whites (P < 0.01). Being foreign-born was the strongest risk factor for TB, regardless of population densities, but APIs were more likely to have TB than foreign-born Whites at lower population densities.

CONCLUSION

Disparities in TB exist among US APIs and non-Hispanic Whites. TB program officials should allocate programs appropriately for foreign-born APIs in lower population density areas.