Case report: Pyrotinib in the treatment of advanced scrotal EMPD combined with sweat gland carcinoma

Extramammary Paget disease (EMPD) is a rare cutaneous intraepithelial adenocarcinoma, which is mostly distributed in areas with sweat gland cells and mainly occurs in the anogenital skin of women. The male genital tract involvement is extremely rare and often occurs with other malignant tumors. Paget's disease in the scrotum with sweat gland carcinoma is even rarer. In the first report of scrotal endocrine sweat gland carcinoma associated with Paget disease by Saidi et al. in 1997, no more than 50 cases have been reported in the relevant research worldwide. Early EMPD combined with sweat gland carcinoma is mainly surgical treatment, and there is no standard treatment plan for advanced EMPD with sweat gland carcinoma. Previous article has reported that chemotherapy such as paclitaxel, fluorouracil, platinum, and vinblastine and molecular targeted therapy based on the genetic test results of patients have certain efficacy. Here, we report a 79-year-old male case diagnosed with human epidermal growth factor receptor 2 (HER-2) overexpression, which was effectively controlled by chemotherapy and anti-HER-2 treatment such as pyrotinib.

Treatment outcomes of advanced/metastatic extramammary Paget's disease in Korean patients: KCSG-RC20-06

BACKGROUND

Extramammary Paget's disease (EMPD) is rare. There are no standard treatments due to its rarity and few clinical trials.

METHODS

The objective of this multicenter study was to investigate treatment outcomes of Korean patients with advanced/metastatic EMPD. Data were collected retrospectively from 14 institutions participating in Korean Cancer Study Group (KCSG) Rare Cancer Committee.

RESULTS

A total of 37 patients were identified. Of these 37 patients, 6 received locoregional therapy as a first-line treatment. In 31 patients who received systemic chemotherapy as a first-line treatment, platinum-based chemotherapy (n = 22) achieved an objective response rate (ORR) of 45.5% and a median progression-free survival (PFS) of 7.89 months. Taxane-based chemotherapy (n = 8) achieved an objective response rate of 62.5% and median PFS of 9.73 months. In second-line chemotherapy, platinum-based chemotherapy (n = 4) had a disease control rate (DCR) of 75.0% and median PFS of 3.45 months. Taxane-based chemotherapy (n = 8) had a DCR of 75.0% and a median PFS of 8.67 months. Six patients received anti-human epidermal growth factor receptor 2 (HER2) antibody during first- and second-line chemotherapy. Overall, systemic chemotherapy combined with anti-HER2 antibody had an ORR of 100% and a median PFS of 13.31 months. The ORR and PFS with systemic chemotherapy combined with trastuzumab was better than platinum- and taxane-based chemotherapy only.

CONCLUSIONS

Due to its rarity, advanced or metastatic EMPD still has no established standard treatment. Results of our study indicate that the combination of trastuzumab with taxane has longer survival than trastuzumab monotherapy or conventional platinum- or taxane-based chemotherapy.

Case Report: Prolonged clinical benefit with sequential trastuzumab-containing treatments in a patient with advanced extramammary Paget disease of the groin

Extramammary Paget disease (EMPD) is a rare form of cutaneous, intraepithelial adenocarcinoma, which typically presents itself as an erythematous plaque originating from apocrine-gland rich regions, such as the vulva, the perianal region, the scrotum, the penis, or the axilla. EMPD patients typically have a good prognosis, with expected 5-year survival of 60%–92%, but it is estimated that about one-third of EMPD patients will develop lymph node or distant metastases. Treatment approaches for EMPD include locoregional therapies such as broad surgical resection, radiotherapy, or topical imiquimod, when the disease is localized, and chemotherapy and biological agents for advanced EMPD. We report the case of a 58-year-old man diagnosed with locally advanced, symptomatic HER2-overexpressing, AR-positive EMPD, who achieved long-term tumor control with a sequence of several trastuzumab-based treatments (more than 30 months with second-line carboplatin plus paclitaxel plus trastuzumab followed by trastuzumab maintenance; 9 months for third-line vinorelbine plus trastuzumab). Even if it is reported that AR expression occurs concomitantly with HER2 overexpression in more than half of the cases of EMPD, to the best of our knowledge, this is the first case report describing androgen receptor blockade therapy in combination with an anti-HER2 agent. Our patient did not benefit from androgen receptor blockade in combination with trastuzumab, thus suggesting that AR expression may simply reflect an intrinsic characteristic of the EMPD cell of origin, rather than tumor dependence upon AR signaling. Given the reported sensibility to anti-HER2 therapy, also new antibody drug conjugates targeting HER2 are worth exploring in the management of advanced EMPD.

Human epidermal growth factor receptor-2 (HER2) is a potential therapeutic target in extramammary Paget’s disease of the vulva

Background

Invasive vulvar Paget’s disease with over-expression of the human epidermal growth factor receptor 2 (HER2) protein is potentially suitable for targeted therapy, especially in a metastatic setting where no effective treatments are available.

Methods

Four consecutive patients with HER2 positive advanced vulvar Paget’s disease, treated with weekly trastuzumab (loading dose 4 mg/kg, then 2 mg/kg) and paclitaxel (80 mg/m2) followed by 3-weekly trastuzumab maintenance (6 mg/kg), are reported.

Results

Median age and follow-up of patients were 62.5 years (45–74) and 16 months (6-54), respectively. Complete or partial responses were observed in all patients. Median time to response was 3 months (range 2–4), while median duration of response was 10 months (range 2–34). Case 1 presented with pulmonary and lymph nodes involvement. She experienced a radiological complete response after 24 treatment administrations, and a progression-free survival of 36 months. At disease progression, treatment re-challenge achieved partial response. She is currently receiving treatment with trastuzumab–emtansine. Case 2 was a 74-year-old woman who developed pulmonary metastasis after first-line cisplatin treatment. She had a partial response and a progression-free survival of 10 months. Case 3 had inguinal and para-aortic lymphadenopathy in complete response after 18 treatment administrations. She developed brain metastasis while receiving trastuzumab maintenance. Case 4 was treated for locally advanced disease and experienced a subjective benefit with relief in perineal pain and itching. No unexpected treatment-related side effects were reported.

Conclusions

Advanced vulvar Paget’s disease is a rare disorder and no standard treatment is available. In the sub-group of HER2 positive disease, weekly paclitaxel–trastuzumab appears to be active and safe, and may be considered a therapeutic option in these patients.