Predicting gas concentration within NGC 6334 MDCs through a mass versus size diagram. Starless MDC candidates in NGC 6334, displayed in filled blue circles, are compared with a handful of massive starless clumps, and prestellar sub-fragments/cores (Bontemps et al. 2010; Butler & Tan 2012; Tan et al. 2013; Duarte-Cabral et al. 2014; Wang et al. 2014, in blue open circles and crosses), respectively. NGC 6334 protostellar MDCs, displayed in filled red circles, are themselves compared to five protostellar MDCs and their embedded high-mass protostars (Motte et al. 2007; Bontemps et al. 2010; Tan et al. 2016, in red open circles and crosses), respectively. The red line and blue dashed line represent mass radial power-laws of Mass ( <r) ∝ r and Mass ( <r) ∝ r², expected to be followed by NGC 6334 protostellar and starless MDCs respectively. The sample of 32 MDCs is too small to present any statistically meaningful mass versus size relation.