Primary Retroperitoneal Lymph Node Dissection as Treatment for Low-volume Metastatic Seminoma in a Population-based Cohort: The Swedish Norwegian Testicular Cancer Group Experience.

Background and objective: There is an unmet need to avoid long-term morbidity associated with standard cytotoxic treatment for low-volume metastatic seminoma. Our aim was to assess the oncological efficacy and surgical safety of retroperitoneal lymph node dissection (RPLND) as treatment in a population-based cohort of metastatic seminoma patients with limited retroperitoneal lymphadenopathy. Methods: Sixty-two seminoma patients in Norway and Sweden were included in the cohort from 2019 to 2022. Patients with lymphadenopathy ≤3 cm, having primary clinical stage (CS) IIA/B or CS I with a relapse, were operated with uni- or bilateral template RPLND, open or robot assisted. The outcome measures included surgical complications as per Clavien-Dindo, and Kaplan-Meier survival estimates for 24-mo progression-free survival (PFS) and overall survival (OS). Key findings and limitations: In the cohort, 33 (53%) had CS I with a relapse during surveillance, six (10%) CS I with a relapse following adjuvant chemotherapy, and 23 (37%) initial CS IIA/B. Metastatic seminoma was verified in 58 patients (94%) with a median largest diameter of 18 mm (interquartile range [IQR] 13-24). Robot-assisted RPLND was performed in 40 patients (65%). Clavien-Dindo III complications were observed in three patients (5%); no grade ≥IV complications occurred. Eighteen patients (29%) received adjuvant chemotherapy after surgery. The median follow-up was 23 mo (IQR 16-30), and recurrence occurred in six patients (10%) after a median of 8 mo (IQR 4-14). PFS was 90% (95% confidence interval: 0.86-1) and OS was 100% at 24 mo. Conclusions and clinical implications: RPLND as primary treatment is an option for selected low-stage seminomas with a limited burden of disease, showing low complications and low relapse rates, with the potential to reduce long-term morbidity. Patient summary: In seminoma patients with limited metastatic spread, surgery is a treatment option offering an alternative to chemotherapy or radiation. This paper covers the first 62 patients operated in Norway and Sweden.

Initial surveillance in men with marker negative clinical stage IIA non-seminomatous germ cell tumours.

OBJECTIVES: To assess whether extended surveillance with repeated computed tomography (CT) scans for patients with clinical stage IIA (CS IIA; <2 cm abdominal node involvement) and negative markers (Mk-) non-seminomatous germ cell tumours (NSGCTs) can identify those with true CS I. To assess the rate of benign lymph nodes, teratoma, and viable cancer in retroperitoneal lymph node dissection (RPLND) histopathology for patients with CS IIA Mk- NSGCT. PATIENTS AND METHODS: Observational prospective population-based study of patients diagnosed 2008-2019 with CS IIA Mk- NSGCT in the Swedish and Norwegian Testicular Cancer Group (SWENOTECA) registry. Patients were managed with surveillance, with CT scans, and tumour markers every sixth week for a maximum of 18 weeks. Patients with radiological regression were treated as CS I, if progression with chemotherapy, and remaining CS IIA Mk- disease with RPLND. The end-point was the number and percentage of patients down-staged to CS I on surveillance and rate of RPLND histopathology presented as benign, teratoma, or viable cancer. RESULTS: Overall, 126 patients with CS IIA Mk- NSGCT were included but 41 received therapy upfront. After surveillance for a median (range) of 6 (6-18) weeks, 23/85 (27%) patients were in true CS I and four (5%) progressed. Of the remaining 58 patients with lasting CS IIA Mk- NSGCT, 16 received chemotherapy and 42 underwent RPLND. The RPLND histopathology revealed benign lymph nodes in 11 (26%), teratoma in two (6%), and viable cancer in 29 (70%) patients. CONCLUSIONS: Surveillance with repeated CT scans can identify patients in true CS I, thus avoiding overtreatment. The RPLND histopathology in patients with CS IIA Mk- NSGCT had a high rate of cancer and a low rate of teratoma.

Cardiac hypertrophy and decreased high-density lipoprotein cholesterol in Lrig3-deficient mice.

Genetic factors confer risk for cardiovascular disease. Recently, large genome-wide population studies have shown associations between genomic loci close to LRIG3 and heart failure and plasma high-density lipoprotein (HDL) cholesterol level. Here, we ablated Lrig3 in mice and investigated the importance of Lrig3 for heart function and plasma lipid levels. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to analyze Lrig3 expression in the hearts of wild-type and Lrig3-deficient mice. In addition, molecular, physiological, and functional parameters such as organ weights, heart rate, blood pressure, heart structure and function, gene expression in the heart, and plasma insulin, glucose, and lipid levels were evaluated. The Lrig3-deficient mice were smaller than the wild-type mice but otherwise appeared grossly normal. Lrig3 was expressed at detectable but relatively low levels in adult mouse hearts. At 9 mo of age, ad libitum-fed Lrig3-deficient mice had lower insulin levels than wild-type mice. At 12 mo of age, Lrig3-deficient mice exhibited increased blood pressure, and the Lrig3-deficient female mice displayed signs of cardiac hypertrophy as assessed by echocardiography, heart-to-body weight ratio, and expression of the cardiac hypertrophy marker gene Nppa. Additionally, Lrig3-deficient mice had reduced plasma HDL cholesterol and free glycerol. These findings in mice complement the human epidemiological results and suggest that Lrig3 may influence heart function and plasma lipid levels in mice and humans.

The structure of the basement membrane zone differs between keloids, hypertrophic scars and normal skin: a possible background to an impaired function.

Scar tissues were collected from patients with keloids, hypertrophic scars and mature scars. Normal skin was obtained from healthy individuals. Clinical attributes were used to select which tissue to obtain but the distribution of the specific hyaluronan (HA) staining was then used for the definite classification of the various scar types. Light microscopic and ultrastructural analyses were performed with an HA-binding probe, antibodies for collagen I and III and staining for mast cells. Ultrastructural studies of keloids revealed an altered collagen structure in the dermal layers, with an abundance of collagen fibres of similar diameter in both the reticular dermis (RD) and the papillary dermis (PD) compared to normal skin. Furthermore, the keloids displayed epidermal changes, which involved the basement membrane (BM), with fewer hemidesmosomes and an altered shape of desmosomes in the entire enlarged spinous layer. The frequency of mast cells found in keloids was lower than in other scar tissues and normal skin. These alterations in epidermis could influence the hydrodynamic and cell regulatory properties of the wounded skin with impaired function and insufficient regulative capacity to hinder the ever-growing collagen tissue that is characteristic for keloids.

Hyaluronan and collagen in human hypertrophic cardiomyopathy: a morphological analysis.

Introduction. The hypertrophic cardiomyopathy (HCM) disease process is not only limited to cardiomyocyte abnormalities but also engages the extracellular matrix. Hyaluronan (HA) and its receptor CD44 are involved in cellular growth and tissue proliferation but have so far been less studied in myocardial hypertrophy. In HCM, collagens are abundant but their histological distribution and relation to hyaluronan have not been described. Material and Methods. Myocardial specimens from 5 patients with symptomatic left ventricular tract obstruction undergoing myectomy due to HCM were processed for histochemistry and immunohistochemistry. Results. HA staining was more intense in HCM patients. The histological distribution of HA was the same in patients and controls, that is, interstitial staining including the space between cardiomyocytes, in fibrous septa, and in the adventitia of intramyocardial blood vessels. CD44 was not detected in the myocardium of patients or controls. Collagen I showed the same general localisation as HA but detailed distribution differed. Conclusions. This is the first study that describes the distribution of hyaluronan in human HCM. HA staining is more intense in HCM patients but without coexpression of its receptor CD44, at least not in the chronic phase of HCM. HA and collagen I have the same localisation.

Parallel up-regulation of FGF-2 and hyaluronan during development of cardiac hypertrophy in rat.

The importance of glycosaminoglycan hyaluronan (HA) and its receptor CD44 in cell proliferation is becoming increasingly evident. Expression of the genes coding for hyaluronan synthase 1 (HAS1), HAS2, HAS3, CD44, fibroblast growth factor-2 (FGF-2), and FGF receptor-1 (FGFR-1) and the histological evidence for increases of HA and CD44 were investigated in an experimental rat model of cardiac hypertrophy. The abdominal aorta was ligated to induce cardiac hypertrophy, and mRNAs prepared from heart tissue were analyzed after 1, 6, and 42 days. The total concentration of HA was quantified, and HA and CD44 were studied histochemically. The expression of HAS1, HAS2, CD44, and FGF-2 was considerably up-regulated at days 1 and 6 and returned to basal levels after 42 days. FGFR-1 was up-regulated at day 1 but at basal levels once more at days 6 and 42. The concentration of HA significantly increased in aorta-ligated rats. Histochemical analysis showed increased expression of CD44 in hypertrophied myocardium mainly in and around the coronary arteries. These results agree well with other studies of tissue growth (malignancies and wound healing). The increase of HA, its synthases, and receptor in parallel with FGF-2 and its receptor illustrates their complicated interplay in the development of cardiac hypertrophy. The up-regulation of both HAS1 and HAS2 indicates the importance of HA production in the hypertrophic process and the possibility that HA is needed for two different purposes for the heart to be able to adapt to the increased afterload caused by aortic ligature.

Hyaluronan and its receptor CD44 in the heart of newborn and adult rats.

The extracellular matrix is a dynamic space and a prerequisite for the function of cardiomyocytes. We have previously reported on the distribution of the glycosaminoglycan hyaluronan (HYA) and its cellular receptor CD44 in the vascular system. In newborn rats, HYA and its receptor were colocalized, but in the adult animals, no such colocalization was observed. Furthermore, the distribution of both HYA and CD44 differed between newborn and adult animals. In this study, the distribution of HYA and its receptor CD44 is explored in the heart. Hearts from newborn and adult rats were stained for visualization of HYA and CD44 using histochemistry and immunohistochemistry. HYA stained the interstitium of the myocardium heterogeneously. Strong staining was seen in the heart valves of both newborn and adult animals. CD44 staining was sparse in hearts from both newborn and adult animals. There are no major changes in the distribution of HYA in the myocardium during the postnatal development in contrast to the blood vessels. Thus, the structure of the interstitium does not change after birth when the heart starts to grow mainly through cardiomyocyte hypertrophy rather than hyperplasia. The abundance of HYA in the heart valves is probably related to their unique physiological properties to withstand repetitive mechanical stress.

Expression of the CD44 receptor in the blood vessel system: an experimental study in rat.

The CD44 receptor is a transmembrane glycoprotein expressed on a variety of cells like endothelial, epithelial and smooth muscle cells. This molecule has many important functions, e.g. in cell-cell and cell-matrix interactions and signal transduction. The main ligand for CD44 is hyaluronan (HYA). HYA is a glycosaminoglycan with structural and cell biological properties. The localization of HYA in the vessel wall of arteries and veins in the healthy adult and newborn rat has been described earlier. In this study the occurrence of the CD44 receptor was investigated in the same vessels and compared to the localization of HYA. Both CD44 and its ligand showed an increased expression in the vessel wall of newborn rats compared to that of adult rats. Although HYA is abundant in the adventitia of adult rats, virtually no expression of CD44 was observed. Our results indicate that the CD44 receptor expression is increased during the stage of maturation of the vessel tree whereas the CD44 receptor is less needed by HYA in the healthy vessel wall.

Hyaluronan is differently located in arteries and veins. An immunohistochemical study in the rat.

The matrix components of the vessel wall are of great importance for the function of the vessel system of which both endurance and elasticity are prerequisites. One component of the vessel wall is the glycosaminoglycan hyaluronan (HYA) with its unique physico-chemical properties, e.g. viscoelasticity and barrier function. The present study aimed to map and compare the normal localisation and distribution of hyaluronan in the arteries and veins of both adult and newborn rats, using a specific staining method utilizing a hyaluronan-binding protein. The hyaluronan stained clearly different in veins and arteries both in newborn and adult rats. In the veins, the tunica intima stained intensely whereas the corresponding area in the arteries only showed a weak and scattered staining pattern. In the adult rats, the matrix between the smooth muscle cells of the tunica media of the veins had a clearly positive staining pattern compared to the media in the arteries which showed only a few scattered areas of positive staining. In the newborn rats, the media of the arteries stained more intensely. In both newborn and adult rats, the adventitia stained intensely both in veins and arteries. Moreover, the HYA-staining pattern differed in veins in different regions of the body. Since HYA is known to be involved in many different biological processes, the results are of importance to understand physiological properties of the vessel tree and to explain the development of vascular diseases.