Background
Definite diagnosis of metastasis from unknown primary depends on a comprehensive immunohistochemical investigation of tumor specimen. Accurate identification of the origin site usually helps a lot in choosing the most appropriate treatment. Molecular characterization provides more chance of a cure. Echoing modern medical development, BRCA1/2 mutations have been correlated with high efficiency of poly(adenosine diphosphate-ribose) polymerase inhibitors in ovarian cancer. While a previous case report demonstrated a surprising cure of platinum-resistant ovarian cancer with BRCA2 mutation by orally administered melphalan. Case presentation: A 53-year-old Taiwanese woman's malignant pleural effusion was diagnosed to be a metastasis from an occult cancer in female genital organ by diligent pathological study despite absence of image evidence. She resolutely refused intravenously administered chemotherapy. After failure of anti-estrogen tamoxifen, orally administered melphalan achieved excellent complete remission. Pathogenic homozygous BRCA1 and BRCA2 mutations were later detected in tumor cells by next-generation sequencing. The same BRCA2 mutation exists in a heterozygous status in the germline deoxyribonucleic acid. Conclusions: This is so far the second report of long-term remission of advanced female genital organ cancer with BRCA mutations achieved by orally administered melphalan. BRCA1/2 mutations and even all "BRCAness" of malignancy, at least ovarian cancer and ovarian-related cancers, probably not only correlate with high efficacy of poly(adenosine diphosphate-ribose) polymerase inhibitors but also lead to a high-potential cure by orally administered melphalan. We recommend that clinical trials that test this assumption be carefully designed and sophisticatedly performed.
Conclusions
This is so far the second report of long-term remission of advanced female genital organ cancer with BRCA mutations achieved by orally administered melphalan. BRCA1/2 mutations and even all "BRCAness" of malignancy, at least ovarian cancer and ovarian-related cancers, probably not only correlate with high efficacy of poly(adenosine diphosphate-ribose) polymerase inhibitors but also lead to a high-potential cure by orally administered melphalan. We recommend that clinical trials that test this assumption be carefully designed and sophisticatedly performed.