Combined small cell lung carcinoma and giant cell carcinoma: a case report

Abstract Background Combined small cell lung carcinoma (SCLC) is defined as SCLC combined with elements of non-small cell lung carcinoma (NSCLC), accounting for approximately 30% of cases of SCLC. However, combined SCLC and giant cell carcinoma (GC) is very rare. Case presentation A 50-year-old woman with a 45 pack-year smoking history was referred to our hospital for further investigation of an abnormal left hilar shadow. Chest computed tomography (CT) revealed a 28-mm solid pulmonary nodule in the left lower lobe and an enlarged left hilar lymph node adjacent to the left main pulmonary artery. CT-guided biopsy of the pulmonary nodule led to the diagnosis of high-grade neuroendocrine carcinoma. The preoperative clinical stage was defined as cT1bN1M0. Thus, the patient underwent left lower lobectomy with ND2a-2 lymph node dissection via thoracotomy. Pathological investigation revealed a 22-mm tumor and dense sheet-like growth of small tumor cells with scant cytoplasm and finely granular nuclear chromatin. Moreover, there was a sheet-like growth of bizarre, highly pleomorphic mono- or occasionally multinucleated giant cells, accounting for approximately 40% of the tumor. Both the small and giant cell components were thyroid transcription factor-1-positive and p40-negative and exhibited neuroendocrine differentiation, as indicated by positivity for synaptophysin and CD56 and negativity for chromogranin A. While the small cell component was E-cadherin-positive and vimentin-negative, the giant cell component was E-cadherin-negative and vimentin-positive, indicating an epithelial-to-mesenchymal transition. Only the small cell component was found within the mediastinal and hilar lymph nodes. The final pathological diagnosis was combined SCLC and GC, pT1bN2M0, and pStage IIIA. The patient received adjuvant chemotherapy with 4 cycles of cisplatin and irinotecan. No sign of recurrence has been noted for 1 year after the surgery. Conclusions This is the first detailed report of a unique case with combined SCLC and GC. The coexistence of SCLC and GC in the presented case might indicate several possibilities: (1) GC may arise from SCLC via epithelial-to-mesenchymal transition, (2) SCLC may arise from GC through phenotypic conversion, and (3) SCLC and GC may have derived from a common neuroendocrine origin. Further investigation is necessary to reveal the underlying pathological process

Assessing land-use and carbon stock in slash-and-burn ecosystems in tropical mountain of Laos based on time-series satellite images

International audienceIn the tropical mountains of Southeast Asia, slash-and-burn (S/B) agriculture is a widely practiced and important food production system. The ecosystem carbon stock in this land-use is linked not only to the carbon exchange with the atmosphere but also with food and resource security. The objective of this study was to provide quantitative information on the land-use and ecosystem carbon stock in the region as well as to infer the impacts of alternative land-use and ecosystem management scenarios on the carbon sequestration potential at a regional scale. The study area was selected in a typical slash-and-burn region in the northern part of Laos. The chrono-sequential changes of land-use such as the relative areas of community age and cropping (C) + fallow (F) patterns were derived from the analysis of time-series satellite images. The chrono-sequential analysis showed that a consistent increase of S/B area during the past three decades and a rapid increase after 1990. Approximately 37% of the whole area was with the community age of 1–5 years, whereas 10% for 6–10 years in 2004. The ecosystem carbon stock at a regional scale was estimated by synthesizing the land-use patterns and semi-empirical carbon stock model derived from in situ measurements where the community age was used as a clue to the linkage. The ecosystem carbon stock in the region was strongly affected by the land-use patterns; the temporal average of carbon stock in 1C + 10F cycles, for example, was greater by 33 MgC ha−1 compared to that in 1C + 2F land-use pattern. The amount of carbon lost from the regional ecosystems during 1990–2004 periods was estimated to be 42 MgC ha−1. The study approach proved to be useful especially in such regions with low data-availability and accessibility. This study revealed the dynamic change of land-use and ecosystem carbon stock in the tropical mountain of Laos as affected by land-use. Results suggest the significant potential of carbon sequestration through changing land-use and ecosystem management scenarios. These quantitative estimates would be useful to better understand and manage the land-use and ecosystem carbon stock towards higher sustainability and food security in similar ecosystem