Background: Breast cancer survivors may experience a broad range of physical and psychosocial long-term and late effects. Although disease-specific guidelines for breast cancer survivorship care are available, systematic approaches remain a challenge in clinical practice. The purpose of this study was to describe variations in how medical oncologists assess and manage specific long-term and late effects in breast cancer survivors. Methods: This study is a secondary analysis of data from a survey of medical oncologists about breast cancer survivorship care in the United States. Using a study-specific list, oncologists were asked to report the “most common” and “most distressing” concerns of breast cancer survivors in their clinical practice, as well as the frequency at which they assess and manage 16 specific long-term and late effects in routine survivorship care. Data was analyzed using descriptive statistics to rank perceived patient concerns and compare practice variations across specific post-treatment issues. Results: Data from 215 surveys were included. Oncologists perceived anxiety, fatigue, neuropathy, and menopausal symptoms as top-ranking common and distressing concerns in breast cancer patients. When asked how often they assess and manage specific long-term and late effects in routine survivorship visits, oncologists reported the highest frequency for neuropathy (55%), bone health (54%), and pain (52%), and the lowest frequency for cognitive impairment (19%), sexual dysfunction (15%), and body image concerns (13%). Cognitive impairment and body image were perceived as the fourth and fifth most distressing issues that breast cancer survivors face, yet oncologists reported routine assessment and management less than 20 percent of the time. Conclusions: Findings from this analysis indicate that oncologists routinely assess and manage certain long-term and late effects, while others remain neglected. Important disconnects between perceived patient concerns and the issues that are routinely addressed in clinical practice were also identified. Standardized approaches that incorporate brief patient-reported assessments across multidimensional issues may facilitate comprehensive, guideline-concordant survivorship care.