Pittelkow, Mark R.

AbstractMatching molecularly targeted therapies with cancer subtype‐specific gene mutations is revolutionizing oncology care. However, for rare cancers this approach is problematic due to the often poor understanding of the disease's natural history and phenotypic heterogeneity, making treatment of these cancers a particularly unmet medical need in clinical oncology. Advanced Sézary syndrome (SS), an aggressive, exceedingly rare variant of cutaneous T‐cell lymphoma (CTCL) is a prototypical example of a rare cancer. Through whole genome and RNA sequencing (RNA‐seq) of a SS patient's tumor we discovered a highly expressed gene fusion between CTLA4 (cytotoxic T lymphocyte antigen 4) and CD28 (cluster of differentiation 28), predicting a novel stimulatory molecule on the surface of tumor T cells. Treatment with the CTLA4 inhibitor ipilimumab resulted in a rapid clinical response. Our findings suggest a novel driver mechanism for SS, and cancer in general, and exemplify an emerging model of cancer treatment using exploratory genomic analysis to identify a personally targeted treatment option when conventional therapies are exhausted.

AbstractBackgroundThe utility of diagnostic imaging in paraneoplastic autoimmune multiorgan syndrome (PAMS) is unknown.MethodsWe examined the role of diagnostic imaging in patients with PAMS evaluated at our tertiary referral center (at Mayo Clinic, Rochester, MN, USA) and in the English literature between January 1, 1996, and August 31, 2012.ResultsWe included 17 patients from our institution and 208 patients from the literature review. Of these 225 patients, 113 (50.2%) were not known to have a malignancy diagnosis at the time of PAMS diagnosis. Of the 123 patients from our institution and from the literature reported to undergo imaging studies, conventional computed tomography (CT) was the predominant imaging modality (n = 110; 89.4%); 18F‐fluorodeoxyglucose (18F‐FDG) positron emission tomography (PET)/CT was also used, albeit infrequently (n = 12; 9.8%). When CT was included in imaging to identify or confirm the presence of a malignancy, imaging was successful in all patients who ultimately were diagnosed with an associated malignancy. At our institution, a relatively high percentage (n = 7; 41%) of patients had 18F‐FDG PET/CT, which not only identified all tumors found on CT but also facilitated staging of lymphoma and guided biopsy procedures.ConclusionDiagnostic imaging is frequently utilized in PAMS with unknown malignancy. Both conventional CT and 18F‐FDG PET/CT are likely to detect the typical underlying neoplasms. Relative to conventional CT, 18F‐FDG PET/CT may provide additional useful information regarding prognosis for the likely underlying malignancies, although there is a paucity of reports describing the use of this modality for this purpose.

AbstractStudying signal transduction in skin‐resident T cells (sr‐T cells) can be limited by the small size of clinical biopsies. Here, we isolated sr‐T cells from clinical samples and analysed signalling protein complexes by multiplex immunoprecipitation detected by flow cytometry (mIP‐FCM). In samples from two independent donors, antigenic stimulation induced signalling proteins to join shared complexes that were observed in seven pairwise combinations among five proteins. This demonstrates that sr‐T cells isolated from small clinical samples provide sufficient material for mIP‐FCM‐based analysis of signalling‐induced protein complexes. We propose that this strategy may be useful for gaining improved mechanistic insight of sr‐T cell signal transduction associated with dermatological disease.

Key Points Alternatively polarized macrophages are abundant constituents of the tumor microenvironment in T-cell lymphoproliferative disorders. GATA-3 expression identifies a subset of PTCL, NOS with a distinct cytokine profile and inferior survival.

BACKGROUNDThe management of pediatric melanoma (PM) has largely been extrapolated from adult data. However, the behavior of PM appears to differ from its adult counterparts. Therefore, an international PM registry was created and analyzed.METHODSTwelve institutions contributed deidentified clinicopathologic and outcome data for patients diagnosed with PM from 1953 through 2008.RESULTSOverall survival (OS) data were reported for 365 patients with invasive PM who had adequate follow‐up data. The mean age of the patients was 16 years (range 1 year‐21 years). The 10‐year OS rate, 80.6%, tended to vary by patient age: 100% for those aged birth to 10 years, 69.7% for those aged > 10 years to 15 years, and 79.5% for those aged > 15 years to 20 years (P = .147). Patients with melanomas measuring ≤ 1 mm had a favorable prognosis (10‐year OS rate of 97%), whereas survival was lower but similar for patients with melanomas measuring > 1 mm to 2 mm, > 2 mm to 4 mm, and > 4 mm (70%, 78%, and 80%, respectively; P = .0077). Ulceration and lymph node metastasis were found to be correlated with worse survival (P = .022 and P = .017, respectively). The 10‐year OS rate was 94.1% for patients with American Joint Committee on Cancer stage I disease, 79.6% for those with stage II disease, and 77.1% for patients with stage III disease (P < .001).CONCLUSIONSTumor thickness, ulceration, lymph node status, and stage were found to be significant predictors of survival in patients with PM, similar to adult melanoma. There is a trend toward increased survival in children aged ≤ 10 years versus adolescents aged > 10 years. Further analyses are needed to probe for potential biological and behavioral differences in pediatric versus adult melanoma. Cancer 2013;119:4012–4019. © 2013 American Cancer Society.