Lymphoscintigraphy and Single-Photon Emission Computed Tomography (SPECT)/CT to Determine Need for Second Sentinel Lymph Node Biopsy for Breast Cancer Recurrence Following Ipsilateral Breast/Axillary Surgery.

BACKGROUND For patients with cN0 breast cancer, sentinel node biopsy (SNB) is performed to confirm metastasis. When cancer recurs after a breast/axillary surgery, performing a second SNB is debatable in terms of its accuracy and significance. However, SNB is often performed because it is less invasive and can provide significant information. This report describes our experience of performing lymphoscintigraphy and single-photon emission computed tomography (SPECT)/CT to determine whether SNB is informative or not in patients who develop ipsilateral breast tumor recurrence (IBTR) following a breast/axillary surgery. CASE REPORT We included 9 patients with breast cancer and a history of ipsilateral breast/axillary surgery who underwent lymphoscintigraphy and SPECT/CT between April 2020 and July 2023. For lymphoscintigraphy, 20-25 MBq of 99mTc-phytate was injected subcutaneously in the areola, and planar images and SPECT/CT were taken at 15 min and 3 h after the injection. In lymphoscintigraphy, radioisotope accumulation was detected in 2 patients at 15 min and 8 patients at 3 h; it was not detected in 1 patient. The accumulation site was only the axilla in 3 patients; other sites including the axilla in 3, and sites outside the axilla in 2. CONCLUSIONS When a patient who previously underwent breast/axillary surgery develops IBTR, the initial surgery may have altered the lymphatic flow. The lymphatic flow varied between the contralateral or ipsilateral internal mammary lymph nodes, contralateral axilla, multidirectional flow, and the axilla alone. Lymphoscintigraphy and SPECT/CT may be useful for early determination of the need for another SNB.

Aerobic H2 production related to formate metabolism in white-rot fungi.

Biohydrogen is mainly produced by anaerobic bacteria, anaerobic fungi, and algae under anaerobic conditions. In higher eukaryotes, it is thought that molecular hydrogen (H2) functions as a signaling molecule for physiological processes such as stress responses. Here, it is demonstrated that white-rot fungi produce H2 during wood decay. The white-rot fungus Trametes versicolor produces H2 from wood under aerobic conditions, and H2 production is completely suppressed under hypoxic conditions. Additionally, oxalate and formate supplementation of the wood culture increased the level of H2 evolution. RNA-seq analyses revealed that T. versicolor oxalate production from the TCA/glyoxylate cycle was down-regulated, and conversely, genes encoding oxalate and formate metabolism enzymes were up-regulated. Although the involvement in H2 production of a gene annotated as an iron hydrogenase was uncertain, the results of organic acid supplementation, gene expression, and self-recombination experiments strongly suggest that formate metabolism plays a role in the mechanism of H2 production by this fungus. It is expected that this novel finding of aerobic H2 production from wood biomass by a white-rot fungus will open new fields in biohydrogen research.

A case of breast squamous cell carcinoma following breast augmentation with liquid silicone injection after 16 years.

BACKGROUND: Breast augmentation has been linked to various complications, including cancerous tumors. The majority type of breast cancer associated with breast augmentation is adenocarcinoma. Primary squamous cell carcinoma (SCC) of the breast is extremely rare in both augmented and non-augmented women. Due to the low incidence, the possible origin and the mechanism of carcinogenesis of the breast SCC are not well understood. Here, we report a rare case of pure SCC 16 years after breast augmentation with liquid silicone injection. CASE PRESENTATION: A 51-year-old Japanese woman was suffered from prolonged breast fluid retention in her left breast. Multiple unknown foreign bodies caused difficulties to investigate the inflammatory focus with ultrasonography. After unsuccessful surgical drainage and antibiotics treatments, the long-standing fluid retention was surgically removed and pathologically investigated. SCC was found in the removed tissue, and the patient underwent a total left mastectomy followed by postoperative chemotherapy. Pathological analysis revealed multiple cystic structures with a hard shell which enclosed high viscous liquid. A qualitative analysis using a Fourier transform infrared spectroscope defined the liquid as pure silicon, which possibly caused the squamous cell carcinogenesis. CONCLUSIONS: Although liquid silicone injection is not a current option for breast augmentation, the injected silicone could result in cancerous tumor generation after years. This case revealed that unphysiological substances could lead to unexpected biological reactions, which caused difficulties in diagnosis with our routine examination. It will be required that accumulate information from more cases and develop novel diagnostic equipment and biomarkers to address these artificial substance-derived tumors.