Interruptions in preventive dermatologic care during crises such as wars or pandemics can lead to delayed detection of malignant skin tumors, resulting in massive, locally invasive lesions, termed dermatologic megatumors. Military populations are particularly vulnerable due to deployment-related constraints, reduced access to specialist care, and limited teledermatology infrastructure. We report three illustrative cases demonstrating the severe clinical and surgical consequences of disrupted dermatologic screening in military personnel. The first case involves a 42-year-old active-duty soldier who developed an invasive Bowen’s carcinoma (cutaneous squamous cell carcinoma, pT3, G2) in the sacral region following two years of delayed evaluation after failed topical therapy. The second case describes a 69-year-old former soldier diagnosed with an ulcerated, superficially spreading malignant melanoma (pT4b, cN3, cM1; Breslow 7.4 mm) of the right gluteal area, already presenting with lymphatic and hepatic metastases at the time of diagnosis. The third case concerns a 47-year-old female soldier with a giant exophytic basal cell carcinoma (7 × 10 × 2 cm) on the lower thoracic back, which required wide excision, vacuum-assisted wound therapy, and reconstruction using a pedicled Limberg flap. Across all cases, interruptions in preventive dermatologic screening led to extensive tumor growth, delayed recognition, and complex surgical management. These cases underscore the critical importance of maintaining dermatologic surveillance even in crisis environments. Preventive strategies, including teledermatology networks, mobile screening units, and mandatory post-deployment skin checks, are essential to prevent the emergence of such advanced malignancies in both civilian and military healthcare contexts.