Bronchiolar adenoma is most easily confused with invasive mucinous adenocarcinoma, especially those with non-papillary proximal bronchiolar adenoma with prominent mucinous features [6, 7]. Because they both have the growth pattern along the alveolar wall, a large number of extracellular mucus and mucus cells can appear discontinuous jump growth mode, and the cells of both could be mild-shaped, which makes the two have amazing similarity in organizational morphology. Due to the obvious differences in the treatment principles and prognosis of the two diseases, it is significant to distinguish them accurately. The key differentiator is the presence of continuous basal cell layers and ciliated cells. In FS, it is easily to identify multilayer basal cells, while it is difficult to identify single layer basal cells. Using P63 and P40 antibody for RD-IHC staining can clearly recognize basal cells and avoid misdiagnosis and missed diagnosis.
The lung SP often presented mass or nodules in CT examination [8, 9]. However, the morphology of is diverse in histopathology. At present, the imaging examinationas and clinical features lack specificity partly because the lower rates of SP. Also, it is difficult to puncture typical lesions via biopsy. Therefore, intraoperative pathologic diagnosis is often needed to determine the surgical method and resection scope. But the accuracy of intraoperative pathologic diagnosis of SP is low, which was easily misdiagnosed as malignant lung tumor, leading to delay treatment. Microscopically, SP showed two kinds of cells (surface and round cell components) and four kinds of structures (papillary, bleeding, solid and sclerosis area). When the lesion is dominated by papillary structures and the other three structures are not obvious, the FS magnify cell atypia and misdiagnosed as invasive adenocarcinoma. The Vimentin and CK7 antibody could be used in RD-IHC to distinguish the two types of mass.
It is difficult to distinguish breast sclerosing adenosis from invasive carcinoma, and there is a certain degree of misdiagnosis rate in X-ray, ultrasound and MRI manifestations [11, 12]. Also, sclerosing adenosis is indistinguishable from carcinoma on microscopy examination. Therefore, pathological diagnosis, especially intraoperative freezing diagnosis, is extremely risky. Most ductal carcinoma in situ may be not difficult to diagnose, but when ductal carcinoma in situ involves sclerosing adenosis with minimal invasion, it presents a great challenge to the pathologist. When the myoepithelial markers, such as P63 and CK5/6, are labeled by RD-IHC, the myoepithelial cells could be clearly displayed and differentiated from invasive cancer easily.
Brain high-grade glioma shows significant nuclear atypia, frequent mitoses, high cell density and obvious microvascular hyperplasia, which is difficult to distinguish with lymphoma morphologically [13, 14]. There is no significant difference between clinical, imaging and laboratory tests. However, the principle of surgical treatment for glioma is maximum safe resection, while surgical resection for lymphoma is controversial. So, intraoperative distinction between high-grade glioma and lymphoma is very important. In this case, RD-IHC staining using GFAP and LCA antibody can serve as an assistant diagnosis of high-grade glioma and lymphoma.
Moreover, RD-IHC staining using CK(AE1/AE3) antibody could also be applied inside resection margin or lymph node, which could play guiding role in surgical procedures.
The practicability of RD-IHC staining in this study is reflected in two aspects: Firstly, the staining method is very simple and easy. Under normal temperature, it only takes one step (1–3 min) to complete antigen and antibody binding. The total staining time is 8–10 min, which is beneficial for technicians to master the method and has strong operability in practical work. Secondly, the staining effect and area was consistent with routine EnVision method. The intensity of staining is similar with no non-specific immunoreactivity and background reactivity.
In this study, antibodies CK(AE1/AE3), CK5/6, P63, P40, GFAP, LCA, syn, Vimentin and CK7 directly labeled with horseradish peroxidase were used for RD-IHC staining in controversial lesions, which significantly improved the intraoperative diagnosis accuracy and reduced delayed diagnosis rate. It could be predicted that more RD-IHC antibodies will be used for c intraoperative pathologic diagnosis of different tissues during surgery. It can have a significant effect on surgical procedures.
In conclusion, rapid intraoperative immunohistochemistry could be a useful tool in intraoperative pathologic diagnosis.