The guidelines project of the Brazilian Society of Pathology aims to disseminate recommendations for pathologists, surgeons, and clinicians, based on solid data from the literature and through adaptations of international guidelines to the reality of Brazilian physicians. This article is the result of the efforts of a group of pathologists, members of the Dermatopathology Committee of the Brazilian Society of Pathology, focused on melanocytic diseases, who, through topics, established pertinent recommendations for clinicians and surgeons for the accurate diagnosis of melanocytic lesions suspected of melanoma. This article aims to clarify the best way to perform excision in cases of suspected melanocytic lesions, as well as the pre-analytical care related to the material, how to interpret the anatomopathological report, and the situations in which immunohistochemical and molecular studies can be auxiliary tools for diagnosis and/or therapy.

The increasing detection of papillary thyroid microcarcinoma (PTMC) has raised concerns regarding overtreatment. For low-risk PTMC, either immediate surgery or active surveillance (AS) can be considered. To facilitate the implementation of AS, the Korean Thyroid Association convened a multidisciplinary panel and developed the first Korean guideline. AS is recommended for adults with pathologically confirmed Bethesda V-VI PTMC who have no clinical evidence of lymph node or distant metastasis, gross extrathyroidal extension, invasion of the trachea or recurrent laryngeal nerve, or aggressive histology. A baseline assessment requires high-resolution neck ultrasound performed by experienced operators to exclude extrathyroidal extension, tracheal or recurrent laryngeal nerve invasion, and lymph node metastasis; contrast-enhanced neck computed tomography is optional. Patient characteristics, including age, comorbidities, and the capacity for long-term follow-up, should be thoroughly assessed. Shared decision-making should carefully weigh the benefits and risks of surgery versus AS, considering expected oncologic outcomes, potential complications, quality of life, anxiety, medical costs, and patient preference. Follow-up involves neck ultrasound and thyroid function tests every 6 months for 2 years and annually thereafter. Disease progression, defined as significant tumor growth or newly detected nodal or distant metastasis, warrants surgery. Despite remaining uncertainties, this guideline provides a structured framework to ensure oncologic safety and supports patient-centered AS.

Colorectal peritoneal metastases (CRPM) represent a significant treatment challenge for patients with colorectal cancer that significantly impact quality of life and limit survival.

The central nervous system World Health Organization (WHO) grade 4 adult-type diffuse glioma represents one of the most aggressive and challenging primary brain tumors. This guideline aims to provide evidence-based recommendations for the multidisciplinary management of these tumors, focusing on diagnosis, initial treatment, reirradiation, and health disparities, while acknowledging that present literature primarily represents historical histologic grade 4 glioblastoma.

Lung cancer remains the number 1 cause of cancer death in men and women in the United States and much of the world. This CHEST organization guideline examines the literature on primary treatment of patients with stage I and II non-small cell lung cancer (NSCLC) to provide evidence-based recommendations.

Appendiceal tumors comprise a heterogeneous group of tumors that frequently disseminate to the peritoneum. Management of appendiceal tumors is lacking high-quality data given their rarity and heterogeneity. In general, appendiceal tumor treatment is extrapolated in part from colorectal cancer or pooled studies, without definitive evidence of disease-specific benefit. Many practices are controversial and vary widely between institutions. A national consensus update of best management practices for appendiceal malignancies was performed to better standardize care. Herein, the authors present recommendations for the management of appendiceal tumors with peritoneal involvement.

Gastric cancer with synchronous peritoneal metastases is a debilitating disease with limited treatment options. This article describes an update of the 2018 Chicago Consensus guidelines addressing the management of gastric cancer with synchronous peritoneal metastases in line with the most recent evidence.

The BSSO developed the present guidelines to provide recommendations based on current scientific evidence that is focused on the main topics related to the daily surgical practice of lymphadenectomy in colorectal cancer. Between October 2024 and February 2025, nine experts met to develop the guidelines for the lymphadenectomy in colorectal cancer. These guidelines summarize concisely the recommendations based on the most current scientific evidence on the most relevant aspects of the lymphadenectomy in colorectal cancer.

The incidence of kidney cancer is rising. It is the 7th most common cancer in men and the 10th most common in women. Diagnosis is based on imaging (thoraco-abdominopelvic computed tomography scan +/- abdominal magnetic resonance) and histopathology. Clear cell carcinoma is the most frequently observed histological subtype. Management of localized kidney cancer involves surgery or ablative treatments. Active surveillance is indicated in the indolent oligometastatic setting with local treatment in case of localized progression. Apart from this specific situation, two first-line therapeutic strategies are recommended in the metastatic setting : a dual immunotherapy regimen or the combination of immunotherapy with an antiangiogenic tyrosine kinase inhibitor. Both combinations have demonstrated superior survival outcomes compared to sunitinib, the previous standard of care until 2019. Treatment selection should be individualized, considering the characteristics of the disease (histology, tumour burden, location of metastases and if they are threatening, speed of progression), potential side effects of the treatments, the patient's general health, comorbidities and preferences.

Advancements in melanoma management have underscored the need for periodic guideline updates every few years to reflect current clinical practices. Previous versions of melanoma clinical practice guidelines in Japan have primarily aimed to reflect global standards of care. This focus on international benchmarks was largely attributed to the scarcity of high-quality evidence from East Asia, necessitating reliance on Western references. Recent findings indicate differences in melanoma subtypes and drug efficacy between Western and East Asian populations. Therefore, efforts were made to incorporate data from East Asia in this revision, aiming to develop guidelines that better reflect the region's unique characteristics. This revision was commissioned by the Japanese Dermatological Association (JDA) and Japanese Skin Cancer Society (JSCS) and was undertaken by a committee comprising experts across relevant fields who meticulously reviewed and systematized a wide range of literature on melanoma to develop comprehensive, evidence-based guidelines. Literature searches were conducted by the Japan Medical Library Association. The recommendation statements were determined using the GRADE Grid approach. The guideline was developed in accordance with the Minds Clinical Practice Guideline Creation Manual 2020, ver. 3.0. Twelve clinical questions (CQs) were established, and corresponding recommendation statements were provided for each CQ. For several CQs, the inclusion of data from East Asia resulted in recommendations that differed from those in Western guidelines. Considering that the biology of melanoma has been increasingly recognized to vary by subtype and ethnicity, guidelines should be developed independently for each region based on evidence specific to the melanoma characteristics of that region. We firmly believe that this Japanese clinical guideline for melanoma will contribute to improving melanoma management in East Asia.

Pituitary tumours, originating from endocrine cells of the anterior pituitary, are quite common, and in most cases well-controlled by surgery or medical treatment. However, a small subset of pituitary tumours presents with multiple local recurrences or tumour progression despite combined surgical, medical or radiotherapeutic treatment. These are known as aggressive pituitary tumours (APT); also called aggressive pituitary neuroendocrine tumours (PitNETs); or, in the rare case of metastases, pituitary carcinomas (PC) or metastatic PitNETs. Early identification of APT is challenging but is of major clinical importance as they are associated with an increased morbidity and mortality even in the absence of metastases. Here, we provide a revision of the first international, interdisciplinary European Society of Endocrinology (ESE) clinical practice guideline on APTs and PC (2018). Since publication of the 2018 guideline, results from the second ESE survey on APT and PC were published, and more data on APT treatment, including temozolomide, immune checkpoint inhibitors and bevacizumab, emerged. These data are reviewed in this guideline and translated into a practical algorithm to guide APT and PC management. Furthermore, standardized reporting of imaging and histopathological investigations of these tumours is proposed, and the role of molecular analysis is discussed. Last, a section is dedicated to special circumstances such as APT in pregnancy.

Despite significant improvements in survival of patients with multiple myeloma (MM), outcomes remain heterogeneous, and a significant proportion of patients experience suboptimal outcomes. Importantly, traditional prognostic factors based on data from patients treated with older therapies no longer capture prognosis accurately in the contemporary era of novel triplet or quadruplet therapies. Therefore, risk stratification requires refinement in the context of available and investigational treatment options in routine practice and clinical trials, respectively. The current identification of high-risk MM (HRMM) in routine practice is based on the Revised International Staging System, which stratifies patients using a combination of widely available serum biomarkers and chromosomal abnormalities assessed via fluorescence in situ hybridization. In recent years, a substantial body of evidence concerning additional clinical, biological, and molecular/genomic prognostic factors has accumulated, along with new MM risk stratification tools and consensus reports. The International Myeloma Society, along with the International Myeloma Working Group, convened an Expert Panel with the primary aim of revisiting the definition of HRMM and formulating a practical and data-driven consensus definition, based on new evidence from molecular/genomic assays, updated clinical data, and contemporary risk stratification concepts. The Panel proposes the following Consensus Genomic Staging (CGS) of HRMM which relies upon the presence of at least one of these abnormalities: (1) del(17p), with a cutoff of >20% clonal fraction, and/or TP53 mutation; (2) an IgH translocation including t(4;14), t(14;16), or t(14;20) along with 1q+ and/or del(1p32); (3) monoallelic del(1p32) along with 1q+ or biallelic del(1p32); or (4) β2 microglobulin ≥5.5 mg/L with normal creatinine (<1.2 mg/dL).

Although the therapeutic options for multiple myeloma have improved survival over time, multiple myeloma tends to relapse and become refractory many times over its course. Unfortunately, the chances of survival of the patients affected diminish with each relapse and consequent line of therapy they receive. The management of multiple myeloma, the therapeutic agents available, and the supportive measures recommended for it have significantly evolved since the Saudi Lymphoma/Myeloma Group published its consensus statement on the management of this disease in 2019. Since updated and clear recommendations adapted to Saudi Arabia are crucial to recognize and appropriately treat different progression patterns in order to counsel patients and healthcare payors, the Saudi Myeloma Working Group has created new recommendations for the management of relapsed and/or refractory multiple myeloma and for the provision of supportive care for clinical specialists in Saudi Arabia to respond to these needs.

This manuscript summarizes the first part of the proceedings of the 2023 Dublin ISUP Consensus Conference encompassing the best practice recommendations on the pathology of neoplasms of urachal origin. The rationale for convening this consensus conference was the lack of structured and consented histopathologic recommendations in these rare tumors. Consensus among the meeting participants (n=80) was reached on the following statements: (1) combination of gross, histologic, clinical and imaging findings with exclusion of secondary tumor metastasis are to be used in the diagnosis of urachal carcinoma; (2) the 2022 World Health Organization (WHO) separate criteria for the diagnosis of urachal adenocarcinoma and for nonglandular carcinoma should be applied; (3) specific elements are to be evaluated and recorded in the gross examination of resection specimens containing urachal tumors; (4) sampling considerations for resection specimens containing urachal tumors are advised; (5) participants are against using 5% or 10% cutoff for the extent of intraepithelial carcinoma in urachal mucinous cystic tumor of low malignant potential; (6) use of immunohistochemical markers for the differential diagnosis of urachal adenocarcinomas in transurethral resection (TUR) specimen is considered optional; (7) similar tumor classificatory (nosology) rules for carcinomas arising from bladder mucosa (eg, urothelial carcinoma, squamous cell carcinoma, and neuroendocrine carcinoma) should be applied for nonglandular urachal carcinomas; (8) a new staging approach other than the previously proposed systems should be designed for urachal carcinoma; (9) a system modifying the current Tumor-Node-Metastasis (TNM)/American Joint Committee on Cancer (AJCC) staging system for urinary bladder cancer is considered appropriate for a study in urachal carcinoma; and (10) several histologic elements are to be reported when diagnosing urachal carcinoma in TUR and resection specimens. This report from the Dublin ISUP consensus conference will serve as a practice recommendation for pathologists and as a guide for future standardized reporting protocols and research regarding urachal tumors. In addition, an international database for urachal cancers under the guidance of ISUP is being planned to be established to address pertinent issues in the pathology of urachal cancers.

The purpose of this consensus statement from the American Brachytherapy Society (ABS) is to summarize important considerations for adding interstitial needles to intracavitary implants for cervix cancer brachytherapy.

Biliary tract cancers (BTC) are aggressive and fatal. Early recognition of symptoms and proper diagnostic work up allow for precise histopathological and molecular classification as well as accurate evaluation of the extent of disease. Surgery is the only potentially curative therapy in localized stages; however, disease recurrence is common and adjuvant chemotherapy appears to improve survival. Upfront systemic chemotherapy with immunotherapy is the treatment of choice in unresectable locally-advanced and metastatic disease. Inroads made in understanding its molecular biology has enabled new therapeutic targets to be identified with current indications and encouraging results that could further improve BTC patients' survival and quality of life.

A significant subset of well-differentiated prostatic acinar neoplasms with invasive histologic features will not spread outside of the prostate, become symptomatic, or shorten a patient's life even if the tumor is left untreated. Overdiagnosis and overtreatment of these indolent prostate cancers (PCa) remain a significant health care problem despite the improved risk assessment and uptake in acceptance of conservative management. While detection of indolent PCa on an entirely resected prostate is possible, recognition of indolent PCa on a needle biopsy (NBX) cannot be reliably made as Grade Group 1 (GG1) PCa diagnosis on NBX is not always identical to one from radical prostatectomy due to a variety of reasons. Further, some of the initially diagnosed GG1 PCas on NBX and carefully monitored on active surveillance (AS) are later reclassified with higher grades. At the same time, other GG1 PCas never progressed on long-term follow-up while receiving no therapy. The overarching goal of this white paper by the 2 leading uropathology organizations, Genitourinary Pathology Society (GUPS) and International Society of Urological Pathology (ISUP), is to help identify a path toward a more meaningful multidisciplinary solution addressing the pervasive problem of overdiagnosis of indolent PCa and its downstream negative effects. Herein, GUPS and ISUP jointly release statements that address why recognition of indolent PCa cannot be reliably made in NBX and why various contemporary multidisciplinary approaches are needed to help improve the detection of indolent PCa in NBX.

Mycosis fungoides (MF) is considered rare in children and adolescents. Accumulating experience indicates that compared with adult patients, almost all paediatric patients with MF are diagnosed at an early stage of disease, exhibit higher rates of atypical presentations and follow a notably indolent course. Despite the need for special staging/investigations specific for children and adolescents, the staging of paediatric MF is currently based primarily on standard practice in adults. The aim of this work was to develop staging recommendations specifically designed for MF in children and adolescents, on behalf of the three largest societies for cutaneous lymphomas, the International Society for Cutaneous Lymphomas, the European Organisation for Research and Treatment of Cancer - Cutaneous Lymphoma Tumor Group, and the United States Cutaneous Lymphoma Consortium. We developed this guideline through an international expert consensus process and in accordance with the EQUATOR Network's recommendations for guideline development. A modified Delphi process was conducted, using questionnaires covering topics including the definition, characteristics and staging of paediatric MF. Two rounds of expert feedback were conducted, with an additional hybrid consensus meeting. We reached a consensus that the term 'paediatric MF' should be reserved for MF diagnosed at ≤ 18 years of age. Panellists specified the unique clinical characteristics of paediatric MF, including a high prevalence of hypopigmented and folliculotropic variants, and reached a consensus on the indolent nature of the disease during childhood and adolescence with rare progression to advanced stage. The consensus reached recommends that while the staging approach is largely similar to that in adults, imaging for early-stage paediatric MF should rely on ultrasound of the lymph nodes if indicated, rather than computed tomography with contrast or integrated with positron emission tomography. Along with this, clinicians should be aware that in children, palpable lymph nodes are common owing to the increased incidence of infectious diseases. In summary, this guideline addresses the major clinical characteristics of paediatric MF, which differ from those in adults, and provides practical staging recommendations considering the safety implications specific for this age group.

Paediatric mycosis fungoides (MF) is characterized by early-stage disease, a strikingly indolent course and high rates of unusual variants. Despite these clinical peculiarities and the special treatment-related safety considerations in children and adolescents, detailed published data on treatments of paediatric MF are scarce, and management is currently based primarily on standard practice in adults. The aim of this work was to develop treatment recommendations specifically designed for MF in children and adolescents, on behalf of the three largest societies for cutaneous lymphomas, the International Society for Cutaneous Lymphomas (ISCL), the European Organisation for Research and Treatment of Cancer - Cutaneous Lymphoma Tumour Group (EORTC-CLTG), and the United States Cutaneous Lymphoma Consortium (USCLC). We developed this guideline through an international expert consensus process and in accordance with the EQUATOR Network's recommendations for guideline development. A modified Delphi process was conducted, using questionnaires covering treatment modalities that are recommended by international guidelines for adult MF. Two rounds of expert feedback were conducted, with an additional one hybrid consensus meeting. Therapeutic recommendations were formulated focusing mainly on early-stage disease. These recommendations take into account disease-specific parameters with therapeutic implications, including the specific stage of the disease, the type of lesion, and the presence of the folliculotropic variant, which is commonly observed in the paediatric age group. Patient-related factors, including safety concerns specific to this young age group, were also addressed. This ISCL/EORTC-CLTG/USCLC guideline provides up-to-date age-specific practical recommendations for the treatment of MF in children and adolescents.