Phase 1 trial of ADI-PEG20 plus cisplatin in patients with pretreated metastatic melanoma or other advanced solid malignancies

Background Arginine depletion interferes with pyrimidine metabolism and DNA damage-repair pathways, and pairing arginine deiminase pegylated with 20,000-molecular-weight polyethylene glycol (ADI-PEG20) with platinum enhances cytotoxicity in vitro and in vivo in arginine auxotrophs.Methods This single-centre, Phase 1 trial was conducted using a 3 + 3 dose escalation designed to assess safety, tolerability and determine the recommended Phase 2 dose (RP2D) of ADI-PEG20.Results We enrolled 99 patients with metastatic argininosuccinate synthetase 1 (ASS1) deficient malignancies. We observed no dose-limiting toxic effects or treatment-related mortality. Three percent of patients discontinued treatment because of toxicity. After treatment, 5% (5/99) of patients had partial responses, and 41% had stable disease. The median progression-free and overall survival durations were 3.62 and 8.06 months, respectively. Substantial arginine depletion and citrulline escalation persisted in most patients through weeks 24 and 8, respectively. Tumour responses were associated with anti-ADI-PEG20 antibody levels at weeks 8 and 16 (p = 0.031 and p = 0.0357, respectively).Conclusion Concurrently administered ADI-PEG20 and cisplatin had an acceptable safety profile and had shown antitumour activity against metastatic ASS1-deficient solid tumours. Further evaluation of this treatment combination is warranted.Subject terms: Cancer, Cancer therapy     

Cutaneous neoplasms composed of melanoma and carcinoma: A rare but important diagnostic pitfall and review of the literature

We report two cases of combined cutaneous tumors composed of melanoma and carcinoma. The first tumor presented as a 5-mm pink-blue macule over the right zygomatic arch in an 85-year-old man. Shave biopsy and immunohistochemical studies revealed that the tumor was composed of melanoma (highlighted by SOX10 and MART-1, with high Ki-67 proliferative index) intermixed with nodular basal cell carcinoma (highlighted by pan-cytokeratin and Ber-EP4). The neoplastic melanocytes were confined to the basal cell carcinoma nodules, and a diagnosis of combined melanoma in situ and basal cell carcinoma was rendered. After therapeutic excision, the patient was disease-free at 9 months after the initial diagnosis. The second tumor presented as a 6-mm pink-brown crusted papule on the right forehead in an 89-year-old man. Shave biopsy and immunohistochemical studies revealed that the tumor was composed of malignant melanoma (MM) (highlighted by S100 and MART-1) intermixed with squamous cell carcinoma (SCC) (highlighted by cytokeratin and p63), and a diagnosis of combined MM-SCC was rendered. These two cases highlight the importance of recognizing these rare types of melanocytic-epithelial cutaneous neoplasms to arrive at an accurate diagnosis that may inform appropriate disease stage and therapy.     

Cutaneous histoplasmosis with prominent parasitization of epidermal keratinocytes: report of a case

Disseminated histoplasmosis most commonly occurs in immunosuppressed individuals and involves the skin in approximately 6% of patients. Cutaneous histoplasmosis with an intraepithelial‐predominant distribution has not been described. A 47‐year‐old man was admitted to our institution with fever and vancomycin‐resistant enterococcal bacteremia. He had been diagnosed with T‐cell prolymphocytic leukemia 4 years earlier and had undergone matched‐unrelated‐donor stem cell transplant 2 years earlier; on admission, he had relapsed disease. His medical history was significant for disseminated histoplasmosis 6 months before admission, controlled with multiple antifungal regimens. During this final hospitalization, the patient developed multiple 2–5 mm erythematous papules, a hemorrhagic crust across the chest, shoulders, forearms, dorsal aspect of the fingers, abdomen and thighs. Skin biopsy revealed clusters of oval yeast forms mostly confined to the cytoplasm of keratinocytes and within the stratum corneum; scattered organisms were present in the underlying superficial dermis without any significant associated inflammatory infiltrate. Special stains and immunohistochemical studies confirmed these to be Histoplasma organisms. We highlight this previously unrecognized pattern of cutaneous histoplasmosis to ensure its prompt recognition and appropriate antifungal therapy.     

Interval breast cancer risk associations with breast density,family history and breast tissue aging

Interval breast cancers (those diagnosed between recommended mammography screens) generally have poorer outcomes and are more common among women with dense breasts. We aimed to develop a risk model for interval breast cancer. We conducted a nested case–control study within the Melbourne Collaborative Cohort Study involving 168 interval breast cancer patients and 498 matched control subjects. We measured breast density using the CUMULUS software. We recorded first-degree family history by questionnaire, measured body mass index (BMI) and calculated age-adjusted breast tissue aging, a novel measure of exposure to estrogen and progesterone based on the Pike model. We fitted conditional logistic regression to estimate odds ratio (OR) or odds ratio per adjusted standard deviation (OPERA) and calculated the area under the receiver operating characteristic curve (AUC). The stronger risk associations were for unadjusted percent breast density (OPERA = 1.99; AUC = 0.66), more so after adjusting for age and BMI (OPERA = 2.26; AUC = 0.70), and for family history (OR = 2.70; AUC = 0.56). When the latter two factors and their multiplicative interactions with age-adjusted breast tissue aging (p = 0.01 and 0.02, respectively) were fitted, the AUC was 0.73 (95% CI 0.69–0.77), equivalent to a ninefold interquartile risk ratio. In summary, compared with using dense breasts alone, risk discrimination for interval breast cancers could be doubled by instead using breast density, BMI, family history and hormonal exposure. This would also give women with dense breasts, and their physicians, more information about the major consequence of having dense breasts—an increased risk of developing an interval breast cancer.